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  • Random Computer Crashes

    - by Josh W.
    Ok, here's a wierd one for you all. Occasionally my PC here at work will crash in a very peculiar way. My dual monitors will suddenly go blank as if there is no longer a video signal, the USB mouse light will go dark and mouse stays unresponsive, the keyboard lights will not change status when the appropriate keys are pressed (Num/Caps/Scoll Lock). The CD Tray WILL open and close. But the computer will not respond to a ping request. For all intents & purposes it's as if the computer is off, except it wasn't intentional by me. The power light and internal fans are still on and I've now lost any unsaved work. Now here's where it gets wierd. This PC is part of a batch of PC's we got from a local vendor who does our initial system builds. Mine, and 6 other co-workers PCs all have the same issue. Originally we thought it was a bad combination of hardware, but through trial and error the only thing we haven't eliminated are the OS, Mobo & CPU. The problem was so bad for some of them that they ended up going back to their 5 year old dinosaurs in order to get some work done, for me the problem isn't as bad, maybe once every other day or so, but still enough to bite me in the ass if I've forgotten my ritualistic pressing of CTRL-S every 1-5 minutes. In this case we've tried two different video cards, two different power supplies, two different memory configurations, running on a UPS/not on UPS, updating/rolling back video drivers, three different bios revisions. The only things we haven't swapped are the mobo & cpu, mainly because a new mobo means a new Hardware Abstraction Layer, ie re-install of windows and there's alot of other software on this PC that takes forever to reload by hand. There was a base image that our systems team created with all the drivers installed and the basic setup of software our company uses, but they then must customize the setup for us programmers so it takes a while to get a new configuration up and going. I'm a programmer by day and am usually pretty good at diagnosing computer problems whether through trial and error or not. We've pretty much exhausted all the ideas we can think of here, short of a new mobo/cpu. Was hoping someone out there might have anything else we can try.. Relevant Parts: OS: XP Pro 32-bit Motherboard: Intel DG41RQ CPU: Intel Core-2 Quad Q9400 @ 2.66GHz Current BIOS Version/Date Intel Corp. RQG4110H.86A.0014.2010.0306.1151, 3/6/2010 Dual LCD's, Viewsonic VG930m & Samsung SyncMaster 910v (other people have different models, but listed in case there's some very wierd problem with the signals being sent/received) PS/2 Keyboard USB Microsoft Intellimouse BIOS Versions Tried: R 0013 12/23/2009 R 0014 3/6/2010 Video cards Tried GeForce 8400 GS Radeon HD 4350 - ASUS EAH4350 Two Different Power Supplies a 380W & 550W Ram Configurations 2GB - 1 x 2GB 4GB - 2 x 2GB

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  • Apache won't follow Symlink

    - by Marvin Dickhaus
    I have a LAMP server (Ubuntu 12.10) setup on my development machine. It is a T60 modified with an SSD. The server base is in /var/www. Apache has the following config: DocumentRoot /var/www <Directory /> Options FollowSymLinks AllowOverride None </Directory> <Directory /var/www/> Options Indexes FollowSymLinks MultiViews SymLinksIfOwnerMatch AllowOverride all Order allow,deny allow from all </Directory> I'm currently developing a SilverStripe CMS featured site. The folder for the server is /var/www/sfk/. The framework and all cms relavant features are in their respective folders. The only folder that need to be modified would be the /var/www/sfk/mysite folder. Because of that I want to keep the mysite folder under my home directory and symlink it into the server folder. So here is what I've done: ln -s ~/sfk/mysite/ /var/www/sfk/ sudo chgrp www-data /var/www/sfk/mysite -R ls tells me the following: /var/www/sfk (exerpt) drwxr-xr-x 3 marvin www-data 4096 Nov 16 16:53 assets drwxr-xr-x 12 marvin www-data 4096 Nov 16 16:53 cms drwxr-xr-x 29 marvin www-data 4096 Nov 16 16:53 framework -rw-r--r-- 1 marvin www-data 2410 Nov 16 16:53 index.php lrwxrwxrwx 1 marvin www-data 24 Nov 20 17:45 mysite -> /home/marvin/sfk/mysite/ -rw-rw-r-- 1 marvin www-data 514 Nov 16 16:55 _ss_environment.php drwxr-xr-x 4 marvin www-data 4096 Nov 16 16:53 themes and ls /var/www/sfk/mysite/ drwxrwxr-x 6 marvin www-data 4096 Nov 16 00:15 code drwxrwxr-x 2 marvin www-data 4096 Nov 16 11:51 _config -rwxrwxr-x 1 marvin www-data 2685 Nov 16 15:39 _config.php drwxrwxr-x 2 marvin www-data 4096 Nov 16 00:15 css drwxrwxr-x 2 marvin www-data 4096 Nov 16 00:15 images drwxrwxr-x 2 marvin www-data 4096 Nov 16 00:15 javascript drwxrwxr-x 5 marvin www-data 4096 Nov 16 00:15 templates This is literally the same setup I have on my desktop machine. The problem I have is that the mysite/ folder is just not recognized. I'm thankful for every advice I get. I'm frustrated because I'm stuck with this issue for hours.

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  • force unattended install php apt debian squeeze

    - by user1258619
    i am trying to do an unattended install via php for several packages but every time when the dependencies come up it aborts instead of forcing the answer to be yes. (i have broken apt a few times...) each time though i start off re-imaging my vps(testing server) so there isn't an issue of something still being hung or crashed.can someone tell me what i am doing wrong? keep in mind this is the 12th version of this script to get nowhere. fwrite(STDOUT, "Root Password:\n"); $root_pass = chop(fgets(STDIN)); $file_apt = '/etc/apt/apt.conf.d/70debconf'; // Open the file to get existing content $current_apt = file_get_contents($file_apt); // Append a new person to the file $current_apt .= "Dpkg::Options {\"--force-confold\";};\n"; // Write the contents back to the file file_put_contents($file_apt, $current_apt); $update = shell_exec('echo '.$root_pass.' | DEBIAN_FRONTEND=noninteractive sudo -S apt-get update'); echo $update; $update_upgrade = shell_exec('echo '.$root_pass.' | DEBIAN_FRONTEND=noninteractive sudo -s apt-get upgrade'); echo $update_upgrade; $install_unattended_mysql = shell_exec('echo '.$root_pass.' | DEBIAN_FRONTEND=noninteractive apt-get install --yes --force-yes mysql-server'); echo $install_unattended_mysql; $install_mysql_set_password = shell_exec('mysql -u root -e "UPDATE mysql.user SET password=PASSWORD("'.$root_pass.'") WHERE user="root"; FLUSH PRIVILEGES;'); echo $install_mysql_set_password; i have read a few places that i needed to edit the apt.conf file so i am doing so here and doing an update and an upgrade. also the upgrade does abort when it actually has to install something. The following packages will be upgraded: apache2 apache2-doc apache2-mpm-prefork apache2-utils apache2.2-bin apache2.2-common base-files bind9 bind9-host bind9utils debian-archive-keyring dpkg dselect libbind9-60 libc-bin libc6 libdns69 libisc62 libisccc60 libisccfg62 liblwres60 locales 22 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. Need to get 18.4 MB of archives. After this operation, 8192 B of additional disk space will be used. Do you want to continue [Y/n]? Abort. I also should note that only a few pieces of software are going to be installed from the apt repo's as i will include some binaries to go along with it.

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  • LdapErr: DSID-0C0903AA, data 52e: authenticating against AD '08 with pam_ldap

    - by Stefan M
    I have full admin access to the AD '08 server I'm trying to authenticate towards. The error code means invalid credentials, but I wish this was as simple as me typing in the wrong password. First of all, I have a working Apache mod_ldap configuration against the same domain. AuthType basic AuthName "MYDOMAIN" AuthBasicProvider ldap AuthLDAPUrl "ldap://10.220.100.10/OU=Companies,MYCOMPANY,DC=southit,DC=inet?sAMAccountName?sub?(objectClass=user)" AuthLDAPBindDN svc_webaccess_auth AuthLDAPBindPassword mySvcWebAccessPassword Require ldap-group CN=Service_WebAccess,OU=Groups,OU=MYCOMPANY,DC=southit,DC=inet I'm showing this because it works without the use of any Kerberos, as so many other guides out there recommend for system authentication to AD. Now I want to translate this into pam_ldap.conf for use with OpenSSH. The /etc/pam.d/common-auth part is simple. auth sufficient pam_ldap.so debug This line is processed before any other. I believe the real issue is configuring pam_ldap.conf. host 10.220.100.10 base OU=Companies,MYCOMPANY,DC=southit,DC=inet ldap_version 3 binddn svc_webaccess_auth bindpw mySvcWebAccessPassword scope sub timelimit 30 pam_filter objectclass=User nss_map_attribute uid sAMAccountName pam_login_attribute sAMAccountName pam_password ad Now I've been monitoring ldap traffic on the AD host using wireshark. I've captured a successful session from Apache's mod_ldap and compared it to a failed session from pam_ldap. The first bindrequest is a success using the svc_webaccess_auth account, the searchrequest is a success and returns a result of 1. The last bindrequest using my user is a failure and returns the above error code. Everything looks identical except for this one line in the filter for the searchrequest, here showing mod_ldap. Filter: (&(objectClass=user)(sAMAccountName=ivasta)) The second one is pam_ldap. Filter: (&(&(objectclass=User)(objectclass=User))(sAMAccountName=ivasta)) My user is named ivasta. However, the searchrequest does not return failure, it does return 1 result. I've also tried this with ldapsearch on the cli. It's the bindrequest that follows the searchrequest that fails with the above error code 52e. Here is the failure message of the final bindrequest. resultcode: invalidcredentials (49) 80090308: LdapErr: DSID-0C0903AA, comment: AcceptSecurityContext error, data 52e, v1772 This should mean invalid password but I've tried with other users and with very simple passwords. Does anyone recognize this from their own struggles with pam_ldap and AD? Edit: Worth noting is that I've also tried pam_password crypt, and pam_filter sAMAccountName=User because this worked when using ldapsearch. ldapsearch -LLL -h 10.220.100.10 -x -b "ou=Users,ou=mycompany,dc=southit,dc=inet" -v -s sub -D svc_webaccess_auth -W '(sAMAccountName=ivasta)' This works using the svc_webaccess_auth account password. This account has scan access to that OU for use with apache's mod_ldap.

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  • Routing table with two NIC adapters in libvirt/KVM

    - by lzap
    I created a virtual NAT network (192.168.100.0/24 network) in my libvirt and new guest with two interfaces - one in this network, one as bridged (10.34.1.0/24 network) to the local LAN. The reason for that is I need to have my own virtual network for my DHCP/TFTP/DNS testing and still want to access my guest externally from my LAN. On both networks I have working DHCP, both giving them IP addresses. When I setup NAT port forwarding (e.g. for ssh), I can connect to the eth0 (virtual network), everything is fine. But when I try to access the eth1 via bridged interface, I have no response. I guess I have problem with my routing table - outgoing packets are routed to the virtual NAT network (which has access to the machine I am connecting from - I can ping it). But I am not sure if this setup is correct. I think I need to add something to my routing table. # ifconfig eth0 Link encap:Ethernet HWaddr 52:54:00:B4:A7:5F inet addr:192.168.100.14 Bcast:192.168.100.255 Mask:255.255.255.0 inet6 addr: fe80::5054:ff:feb4:a75f/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:16468 errors:0 dropped:27 overruns:0 frame:0 TX packets:6081 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:22066140 (21.0 MiB) TX bytes:483249 (471.9 KiB) Interrupt:11 Base address:0x2000 eth1 Link encap:Ethernet HWaddr 52:54:00:DE:16:21 inet addr:10.34.1.111 Bcast:10.34.1.255 Mask:255.255.255.0 inet6 addr: fe80::5054:ff:fede:1621/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:34 errors:0 dropped:0 overruns:0 frame:0 TX packets:189 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:4911 (4.7 KiB) TX bytes:9 # route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 192.168.100.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 10.34.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 169.254.0.0 0.0.0.0 255.255.0.0 U 1002 0 0 eth0 169.254.0.0 0.0.0.0 255.255.0.0 U 1003 0 0 eth1 0.0.0.0 192.168.100.1 0.0.0.0 UG 0 0 0 eth0 Network I am trying to connect from is different than network the hypervisor is connected to: 10.36.0.0. But it is accessible from that network. So I tried to add new route rule: route add -net 10.36.0.0 netmask 255.255.0.0 dev eth1 And it is not working. I thought setting correct interface would be sufficient. What is needed to get my packets coming through?

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  • Group traffic shaping with traffic control?

    - by mmcbro
    I'm trying to limit the output bandwidth generated by an application with linux tc. This application sends me the source port of the request that I use has a filter to limit each user at a given downloadspeed. I feel that my setup could be managed way better if I had a better knowledge of linux tc. At the application level users are categorized as members of a group, each group have a limited bandwidth. Example : Members of group A : 512kbit/s Members of group B : 1Mbit/s Members of group C : 2Mbit/s When a user connects to the application, it retrieves the source port to the origin of the request from the user and sends me the source port and the bandwidth at which the user must be limited depending on group to which it belongs. With these informations I must add the appropriate rules so that the user (the source port in reality) is limited to the right bandwidth. If the user that connect isn't a member of any group it should be limited at a default bandwidth speed. I'm actually managing this by using a self made daemon that add or remove rules from when it receive a request from the application. With my little knowledge of tc I'm not able to limit other users (ones that aren't in a group, all others in fact) at a default speed and my configuration seems awful to me. Here is the base of my tc qdisc and classes : tc qdisc add dev eth0 root handle 1: htb tc class add dev eth0 parent 1: classid 1:1 htb rate 100mbps ceil 125mbps To classify a user at a given speed I have to add one subclass and then associate one filter to it : # a member of group A tc class add dev eth0 parent 1:1 classid 1:11 htb rate 512kbps ceil 512kbps # tts associated filter to match his source port tc filter add dev eth0 protocol ip parent 1:0 prio 1 u32 match ip sport 50001 flowid 1:11 # a member of group A again tc class add dev eth0 parent 1:1 classid 1:12 htb rate 512kbps ceil 512kbps # tts associated filter to match his source port tc filter add dev eth0 protocol ip parent 1:0 prio 1 u32 match ip sport 61524 flowid 1:12 # a member of group B again tc class add dev eth0 parent 1:1 classid 1:13 htb rate 1000kbps ceil 1000kbps # tts associated filter to match his source port tc filter add dev eth0 protocol ip parent 1:0 prio 1 u32 match ip sport 57200 flowid 1:13 I already know that a source port could be the same if its coming from a different IP address the thing is the application is behind a proxy so I don't have to manage any IP address in that situation. I would like to know how to manage the fact that for all other users (request/source port, whatever you name it) could be limited at a given speed each. I mean that each connection should be able to use at max 100kbit/s for example, not a shared 100kbit/s. I also would like to know if there is a way to simplify my rules. I don't know if it is possible to use only one class per group and associate multiple filters to the same class so each users could be handled by one class and not one class per user. I appreciate any advice, thanks.

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  • recommendations for efficient offsite remote backup solution of vm's

    - by senorsmile
    I am looking for recommendations for backing up my current 6 vm's(and soon to grow to up to 20). Currently I am running a two node proxmox cluster(which is a debian base using kvm for virtualization with a custom web front end to administer). I have two nearly identical boxes with amd phenom II x4's and asus motherboards. Each has 4 500 GB sata2 hdd's, 1 for the os and other data for the proxmox install, and 3 using mdadm+drbd+lvm to share the 1.5 TB's of storage between the two machines. I mount lvm images to kvm for all of the virtual machines. I currently have the ability to do live transfer from one machine to the other, typically within seconds(it takes about 2 minutes on the largest vm running win2008 with m$ sql server). I am using proxmox's built-in vzdump utility to take snapshots of the vm's and store those on an external harddrive on the network. I then have jungledisk service (using rackspace) to sync the vzdump folder for remote offsite backup. This is all fine and dandy, but it's not very scalable. For one, the backups themselves can take up to a few hours every night. With jungledisk's block level incremental transfers, the sync only transfers a small portion of the data offsite, but that still takes at least a half an hour. The much better solution would of course be something that allows me to instantly take the difference of two time points (say what was written from 6am to 7am), zip it, then send that difference file to the backup server which would instantly transfer to the remote storage on rackspace. I have looked a little into zfs and it's ability to do send/receive. That coupled with a pipe of the data in bzip or something would seem perfect. However, it seems that implementing a nexenta server with zfs would essentially require at least one or two more dedicated storage servers to serve iSCSI block volumes (via zvol's???) to the proxmox servers. I would prefer to keep the setup as minimal as possible (i.e. NOT having separate storage servers) if at all possible. I have also briefly read about zumastor. It looks like it could also do what I want, but it appears to have halted development in 2008. So, zfs, zumastor or other?

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  • Windows 7 losing one of my displays after restart

    - by j_kubik
    I have an Intel DZ68BC motherboard with Intel HD graphics card using two monitors (on DVI and on HDMI » VGA). My friend asked me to test if his NVIDIA graphics card works well on my computer (at his it was doing some trouble), so I inserted it in my computer, installed the NVIDIA driver and it worked quite well. Then I removed it, uninstalled everything NVIDIA-related I could find and switched monitors back to my Intel card. Since then after every system start/restart, the system sees only monitor on HDMI » VGA connector, completely ignoring the DVI monitor. I noticed that installing the Intel video drivers causes the system to recognize the second monitor if I don't immediately reboot. After a reboot, the system recognizes only the HDMI » VGA monitor. I also tried starting in safe-mode and using DriveSweeper to remove the remains of NVIDIA drivers. While it seems that some drivers were removed, the situation didn't change. Now I am out of ideas and I really wouldn't like to reinstall the system (again...). I also tried restoring the system to the state before this whole story, but it also didn't change anything. EDIT: I am still trying to troubleshoot this problem. The only point that I could start was driver re-instalation. I traced down the part that restores right settings to a call: C:\Users\Jarek\Desktop\GFX_Win7_64_8.15.10.2696\x64\Drv64.exe -driverinf "C:\Users\Jarek\Desktop\GFX_Win7_64_8.15.10.2696\Graphics\igdlh64.inf" -flags 20 -keypath "Software\Intel\Difx64" This call fixes my displays, and as workaround, I will add it for now to my autorun. I am still looking for better solution anyway... EDIT2: Using DriverView i made a list of currently used drivers both before and after fixing my display using above command. Then i compared logs: No drivers were removed by fixing command. Drivers added by fixing command: MS Remote Access serial network driver (asyncmac.sys) security processor (spsys.sys) Drivers that changed base address (indicates driver-reload?) Canonical Display Driver (cdd.dll) Intel Graphics Kernel Mode Driver (igdkmd64.sys) Monitor Driver (monitor.sys) Added drivers seem rather unrelated to the problem to me, reloaded drivers are just a cnsequence of installing new driver file so there is not much to go here... I really cannot make heads or tails out of it...

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  • Linux service --status-all shows "Firewall is stopped." what service does firewall refer to?

    - by codewaggle
    I have a development server with the lamp stack running CentOS: [Prompt]# cat /etc/redhat-release CentOS release 5.8 (Final) [Prompt]# cat /proc/version Linux version 2.6.18-308.16.1.el5xen ([email protected]) (gcc version 4.1.2 20080704 (Red Hat 4.1.2-52)) #1 SMP Tue Oct 2 22:50:05 EDT 2012 [Prompt]# yum info iptables Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * base: mirror.anl.gov * extras: centos.mirrors.tds.net * rpmfusion-free-updates: mirror.us.leaseweb.net * rpmfusion-nonfree-updates: mirror.us.leaseweb.net * updates: mirror.steadfast.net Installed Packages Name : iptables Arch : x86_64 Version : 1.3.5 Release : 9.1.el5 Size : 661 k Repo : installed .... Snip.... When I run: service --status-all Part of the output looks like this: .... Snip.... httpd (pid xxxxx) is running... Firewall is stopped. Table: filter Chain INPUT (policy DROP) num target prot opt source destination 1 RH-Firewall-1-INPUT all -- 0.0.0.0/0 0.0.0.0/0 Chain FORWARD (policy DROP) num target prot opt source destination 1 RH-Firewall-1-INPUT all -- 0.0.0.0/0 0.0.0.0/0 Chain OUTPUT (policy ACCEPT) num target prot opt source destination Chain RH-Firewall-1-INPUT (2 references) ....Snip.... iptables has been loaded to the kernel and is active as represented by the rules being displayed. Checking just the iptables returns the rules just like status all does: [Prompt]# service iptables status Table: filter Chain INPUT (policy DROP) num target prot opt source destination 1 RH-Firewall-1-INPUT all -- 0.0.0.0/0 0.0.0.0/0 Chain FORWARD (policy DROP) num target prot opt source destination 1 RH-Firewall-1-INPUT all -- 0.0.0.0/0 0.0.0.0/0 Chain OUTPUT (policy ACCEPT) num target prot opt source destination Chain RH-Firewall-1-INPUT (2 references) .... Snip.... Starting or restarting iptables indicates that the iptables have been loaded to the kernel successfully: [Prompt]# service iptables restart Flushing firewall rules: [ OK ] Setting chains to policy ACCEPT: filter [ OK ] Unloading iptables modules: [ OK ] Applying iptables firewall rules: [ OK ] Loading additional iptables modules: ip_conntrack_netbios_n[ OK ] [Prompt]# service iptables start Flushing firewall rules: [ OK ] Setting chains to policy ACCEPT: filter [ OK ] Unloading iptables modules: [ OK ] Applying iptables firewall rules: [ OK ] Loading additional iptables modules: ip_conntrack_netbios_n[ OK ] I've googled "Firewall is stopped." and read a number of iptables guides as well as the RHEL documentation, but no luck. As far as I can tell, there isn't a "Firewall" service, so what is the line "Firewall is stopped." referring to?

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  • How to allow unprivileged apache/PHP to do a root task (CentOS)

    - by Chris
    I am setting up a sort of personal dropbox for our customers on a CentOS 6.3 machine. The server will be accessible thru SFTP and a proprietary http service base on PHP. This machine will be in our DMZ so it has to be secure. Because of this I have apache running as an unprivileged user, hardened the security on apache, the OS, PHP, applied a lot of filtering in iptables and applied some restrictive TCP Wrappers. Now you might have suspected this one was coming, SELinux is also set to enforcing. I'm setting up PAM to use MySQL so my users in the web application can login. These users will all be in a group that can use SSH only for SFTP and users will be chrooted to their own 'home' folder. To allow this SELinux wants the folders to have the user_home_t tag. Also the parent directory needs to be writable by root only. If these restrictions are not met SELinux will kill the SSH pipe immediately. The files that need to be accessible thru both http and SFTP so I have made a SELinux module to allow Apache to search/attr/read/write etc. to directories with the user_home_dir_t tag. As sftp users are stored in MySQL I want to setup their home dirs upon user creation. This is a problem since Apache has no write access to the /home dir, it's only writable by root since it's required to keep SELinux and OpenSSH happy. Basically I need to let Apache do only a few tasks as root and only within /home. So I need to somehow elevate the privileges temporarily or let root do these tasks for apache instead. What I need to have apache do with root privileges is the following. mkdir /home/userdir/ mkdir /home/userdir/userdir chmod -R 0755 /home/userdir umask 011 /home/userdir/userdir chcon -R -t user_home_t /home/userdir chown -R user:sftp_admin /home/userdir/userdir chmod 2770 /home/userdir/userdir This would create a home for the user, now I have an idea that might work, cron. That would mean the server needs to check for users that have no home every minute, then when creating users the interface would freeze for an average of 30 seconds before the account creation can be confirmed which I do not prefer. Does anybody know if something can be done with sudoers? Or any other idea's are welcome... Thanks for your time!

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  • Choosing parts for a high-spec custom PC - feedback required [closed]

    - by James
    I'm looking to build a high-spec PC costing under ~£800 (bearing in mind I can get the CPU half price). This is my first time doing this so I have plenty of questions! I have been doing lots of research and this is what I have come up with: http://pcpartpicker.com/uk/p/j4lE Usage: I will be using it for Adobe CS6, rendering in 3DS Max, particle simulations in Realflow and for playing games like GTA IV (and V when it comes out), Crysis 1/2, Saints Row The Third, Deus Ex HR, etc. Questions: Can you see any obvious problem areas with the current setup? Will it be sufficient for the above usage? I won't be doing any overclocking initially. Is it worth buying the H60 liquid cooler, or will the fan that comes with the CPU be sufficient? Is water cooling generally quieter? Is the chosen motherboard good for the current components? And is it future-proof? I read that the HDD is often the bottleneck when it comes to gaming. I presume this is true to other high-end applications? If so, is my selection good? I keep changing my mind about the GPU; first the 560, now the 660. Can anyone shed some light on how to choose? I read mixed opinions about matching the GPU to the CPU. Will the 560 or the 660 be sufficient for my required usage? Atm I'm basing my choice on the PassMark benchmarks and how much they cost. The specs on the GeForce website state that the 560 and the 660 both require 450W. Is this a good figure to base the wattage of my PSU on? If so, how do you decide? Do I really need 750W? The latest GTX 690 requires 650W. Is it a good idea to buy a 750W PSU now to future-proof myself?

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  • Excel 2010: dynamic update of drop down list based upon datasource validation worksheet changes

    - by hornetbzz
    I have one worksheet for setting up the data sources of multiple data validation lists. in other words, I'm using this worksheet to provide drop down lists to multiple other worksheets. I need to dynamically update all worksheets upon any of a single or several changes on the data source worksheet. I may understand this should come with event macro over the entire workbook. My question is how to achieve this keeping the "OFFSET" formula across the whole workbook ? Thx To support my question, I put the piece of code that I'm trying to get it working : Provided the following informations : I'm using such a formula for a pseudo dynamic update of the drop down lists, for example : =OFFSET(MyDataSourceSheet!$O$2;0;0;COUNTA(MyDataSourceSheet!O:O)-1) I looked into the pearson book event chapter but I'm too noob for this. I understand this macro and implemented it successfully as a test with the drop down list on the same worksheet as the data source. My point is that I don't know how to deploy this over a complete workbook. Macro related to the datasource worksheet : Option Explicit Private Sub Worksheet_Change(ByVal Target As Range) ' Macro to update all worksheets with drop down list referenced upon ' this data source worksheet, base on ref names Dim cell As Range Dim isect As Range Dim vOldValue As Variant, vNewValue As Variant Dim dvLists(1 To 6) As String 'data validation area Dim OneValidationListName As Variant dvLists(1) = "mylist1" dvLists(2) = "mylist2" dvLists(3) = "mylist3" dvLists(4) = "mylist4" dvLists(5) = "mylist5" dvLists(6) = "mylist6" On Error GoTo errorHandler For Each OneValidationListName In dvLists 'Set isect = Application.Intersect(Target, ThisWorkbook.Names("STEP").RefersToRange) Set isect = Application.Intersect(Target, ThisWorkbook.Names(OneValidationListName).RefersToRange) ' If a change occured in the source data sheet If Not isect Is Nothing Then ' Prevent infinite loops Application.EnableEvents = False ' Get previous value of this cell With Target vNewValue = .Value Application.Undo vOldValue = .Value .Value = vNewValue End With ' LOCAL dropdown lists : For every cell with validation For Each cell In Me.UsedRange.SpecialCells(xlCellTypeAllValidation) With cell ' If it has list validation AND the validation formula matches AND the value is the old value If .Validation.Type = 3 And .Validation.Formula1 = "=" & OneValidationListName And .Value = vOldValue Then ' Debug ' MsgBox "Address: " & Target.Address ' Change the cell value cell.Value = vNewValue End If End With Next cell ' Call to other worksheets update macros Call Sheets(5).UpdateDropDownList(vOldValue, vNewValue) ' GoTo NowGetOut Application.EnableEvents = True End If Next OneValidationListName NowGetOut: Application.EnableEvents = True Exit Sub errorHandler: MsgBox "Err " & Err.Number & " : " & Err.Description Resume NowGetOut End Sub Macro UpdateDropDownList related to the destination worksheet : Sub UpdateDropDownList(Optional vOldValue As Variant, Optional vNewValue As Variant) ' Debug MsgBox "Received info for update : " & vNewValue ' For every cell with validation For Each cell In Me.UsedRange.SpecialCells(xlCellTypeAllValidation) With cell ' If it has list validation AND the validation formula matches AND the value is the old value ' If .Validation.Type = 3 And .Value = vOldValue Then If .Validation.Type = 3 And .Value = vOldValue Then ' Change the cell value cell.Value = vNewValue End If End With Next cell End Sub

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  • Pushing Large Files to 500+ Computers [closed]

    - by WMIF
    I work with a team to manage 500-600 rented Windows 7 computers for an annual conference. We have a large amount of data that needs to be synced to these computers, up to 1 TiB. The computers are divided into rooms and connected through unmanaged gigabit switches. We prepare these computers ahead of time with the Windows installation and configuration, plus any files that we have available to us before we send the base image in for replication by the rental company. Every year, we have presenters approach on site with up to gigs of data that need to be pushed to the room that they will be presenting in. Sometimes they only have a few files that are small sizes, such as a slide PDF, but can sometimes be much larger 5 GiB. Our current strategy for pushing these files is using batch scripts and RoboCopy. For the large pushes, we actually use a BitTorrent client to generate a torrent file, and then we use the batch-RoboCopy to push the torrent into a folder on the remote machines that is being monitored by an installed BT client. Often times, this data needs to be pushed immediately with a small time window. We have several machines in a control room that are identical to the machines on the floor that we use for these pushes. We occasionally have a need to execute a program on the remote machines, and we currently use batch and PSexec to handle this task. We would love to be able to respond to these last minute pushes with "sorry, your own fault", but it won't happen. The BT method has allowed us to have a much faster response time, but the whole batch process can get messy when there are multiple jobs being pushed. We use Enterprise Ghost for other processes, and it doesn't work well in this large of scale, plus it is really quite expensive for a once-a-year task like this. EDIT: There is a hard requirement that the remote machines on the floor are running Windows. The control machines do not have a hard OS requirement. I would really like to stay away from Multicast because of complications with upstream routers. Is Multicast or BitTorrent the better way to go on this? Is there another protocol that might work better?

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  • BlueScreens on my ThinkPad with Windows 7 64 Bit and a SSD (CRITICAL_OBJECT_TERMINATION, ntoskernel.exe)

    - by pvorb
    I'm getting BlueScreens about every five days for more than three months. Here's an example: A problem has been detected and Windows has been shut down to prevent damage to your computer. The problem seems to be caused by the following file: ntoskrnl.exe CRITICAL_OBJECT_TERMINATION If this is the first time you've seen this stop error screen, restart your computer. If this screen appears again, follow these steps: Check to make sure any new hardware or software is properly installed. If this is a new installation, ask your hardware or software manufacturer for any Windows updates you might need. If problems continue, disable or remove any newly installed hardware or software. Disable BIOS memory options such as caching or shadowing. If you need to use safe mode to remove or disable components, restart your computer, press F8 to select Advanced Startup Options, and then select Safe Mode. Technical Information: *** STOP: 0x000000f4 (0x0000000000000003, 0xfffffa80065f2b30, 0xfffffa80065f2e10, 0xfffff80002f9bf40) *** ntoskrnl.exe - Address 0xfffff80002c98d00 base at 0xfffff80002c19000 DateStamp 0x4d9fdd5b It's has always been the same BlueScreen message showing CRITICAL_OBJECT_TERMINATION, 0x000000f4, and ntoskrnl.exe. Of course the addresses change. My computer is a ThinkPad T400 (about 2 years old) with a SSD in it. I'm also running Windows 7 Professional 64 bit. When I bought my computer, it had a 250GByte SeaGate HDD in it, which I replaced by a 500GByte HDD by Western Digital. Last september I bought a Corsair F120 SSD and replaced the HDD by this SSD. Then I bought a LEICKE HDD adapter for the UltraBay II where I plugged in my 500GByte HDD. This configuration ran about half a year without any errors. After re-installing Windows this spring, I am getting regular BlueScreens. Sometimes my system runs for about 2 weeks without a BSOD, sometimes I get several BlueScreens a day. The only thing that I noticed is, that I'm always running Google Chrome when it happens. Is there anyone who has made his/her own bad experiences whith some of my components or is there anybody who can tell me if it would be helpful to send my notebook to Lenovo? Thank you very much for your help on my issue! Regards, Paul

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  • [CentOS 4.8] nslookup resolves domains to IPs, but I can't get a response to pings to external servers

    - by Beco
    I have a fresh install of CentOS 4.8 running on an internal development server. I haven't done anything to it besides setting up sudoers and SSH. I can SSH into the server and from there resolve domains to IPs and ping internal servers, but for some reason I don't get any response from pinging external servers. The software firewall is disabled, and the problem is present with both static and DHCP-assigned network configurations. The network domain controller is a Windows Server 2003 box. $ nslookup google.com Server: 10.254.2.5 Address: 10.254.2.5#53 Non-authoritative answer: Name: google.com Address: 74.125.47.147 Name: google.com Address: 74.125.47.99 <etc...> 10.254.2.5 is the Win2K3 server. $ ping google.com PING google.com (74.125.47.106) 56(84) bytes of data. It just hangs here indefinitely. $ cat /etc/resolv.conf ; generated by /sbin/dhclient-script search <...snip...>.local nameserver 10.254.2.5 nameserver 10.254.2.124 10.254.2.124 is the backup DC server, which is currently off and tombstoned by this point. The snipped section is our company name. # ifconfig eth0 Link encap:Ethernet HWaddr <snip> inet addr:10.254.2.101 Bcast:10.254.2.255 Mask:255.255.255.0 inet6 addr: <snip>/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:80066 errors:0 dropped:0 overruns:0 frame:0 TX packets:4421 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:7810133 (7.4 MiB) TX bytes:590550 (576.7 KiB) Interrupt:225 Base address:0xc000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:32 errors:0 dropped:0 overruns:0 frame:0 TX packets:32 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:8104 (7.9 KiB) TX bytes:8104 (7.9 KiB) # route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 10.254.2.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth0 0.0.0.0 10.254.2.5 0.0.0.0 UG 0 0 0 eth0 And, for good measure, a snapshot of the current ethernet config via the system-config-network GUI. Edit: I don't yet have enough rep to post images, so here's a link. Sorry! system-config-network snapshot I'm pretty green when it comes to setting up *nix dev servers and network configuration in general, so please let me know if I've left out critical information, or posted information I shouldn't have posted. Thanks!

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  • No external network on ubuntu 9.10, though dns works..

    - by user29368
    Hi, I have a weird problem I cant solve. I have several computers, two with xubuntu 9.10 One of them, acting as a media server, has stopped to work when it comes to external network.. I can do for example: ping google.com Which gives me an ip adress back, like: name@Media:/etc$ ping google.com PING google.com (66.102.9.147) 56(84) bytes of data. That tells me it reaches the dns?, but I get no response at all... If I ping a local computer all works fine. I can also reach the computer via ssh without any problems. I have always used network manager, but now I uninstalled it and made the settings manually like this: /etc/network/interfaces auto lo iface lo inet loopback auto eth0 iface eth0 inet static address 192.168.1.52 netmask 255.255.255.0 network 192.168.1.0 broadcast 192.168.1.255 gateway 192.168.1.1 Still no luck. I have no specific settings for this one in my router, and all the other computers, including my win laptop works fine. This is very annoying since I cant even do an update or anything.. ifconfig looks like this: eth0 Link encap:Ethernet HWaddr 00:24:1d:9f:10:89 inet addr:192.168.1.52 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::224:1dff:fe9f:1089/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:15410 errors:0 dropped:0 overruns:0 frame:0 TX packets:2693 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:1167398 (1.1 MB) TX bytes:694973 (694.9 KB) Interrupt:27 Base address:0xe000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:2150 errors:0 dropped:0 overruns:0 frame:0 TX packets:2150 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:143456 (143.4 KB) TX bytes:143456 (143.4 KB) route -n like this Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 169.254.0.0 0.0.0.0 255.255.0.0 U 1000 0 0 eth0 0.0.0.0 192.168.1.1 0.0.0.0 UG 100 0 0 eth0 I do not know where the adress starting with 169.254 comes from.. Could that be a part of the problem? Hoping for some assistance since Im totally stuck here.. /george

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  • SharePoint 2010 – Central Admin tooling to create host header site collections

    - by eJugnoo
    Just like SharePoint 2007, you can create host-header based site collections in SharePoint 2010 as well. It means, that you do not necessarily need to create a site-collection under a managed path like /sites/, you can create multiple root-level site collections on same web-application/port by using host-header site collections. All you need to do is point your domain or sub-domain to your web-application and create a matching site-collection that you want. But, just like in 2007, it is something that you do by using STSADM, and is not available on Central Admin UI in 2010 as well. Yeah, though you can now also use PowerShell to create one: C:\PS>$w = Get-SPWebApplication http://sitename   C:\PS>New-SPSite http://www.contoso.com -OwnerAlias "DOMAIN\jdoe" -HostHeaderWebApplication $w -Title "Contoso" -Template "STS#0"   This example creates a host header site collection. Because the template is provided, the root Web of this site collection will be created. .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } I’ve been playing with WCM in SharePoint 2010 more and more, and for that I preferred creating hosts file entries for desired domains and create site-collections by those headers – in my dev environment. I used PowerShell initially, but then got interested to build my own UI on Central Admin instead. Developed with Visual Studio 2010 So I used new Visual Studio 2010 tooling to create an empty SharePoint 2010 project. Added an application page (there is no option to add _Admin page item in VS 2010 RC), that got created in Layouts “mapped” folder. Created a new Admin mapped folder for 14-“hive”, and moved my new page there instead. Yes, I didn’t change the base class for page, its just that it runs under _admin, but it is indeed a LayoutsPageBase inherited page. To introduce a action-link in Central Admin console, I created following element: 1: <Elements xmlns="http://schemas.microsoft.com/sharepoint/"> 2: <CustomAction 3: Id="CreateSiteByHeader" 4: Location="Microsoft.SharePoint.Administration.Applications" 5: Title="Create site collections by host header" 6: GroupId="SiteCollections" 7: Sequence="15" 8: RequiredAdmin="Delegated" 9: Description="Create a new top-level web site, by host header" > 10: <UrlAction Url="/_admin/OfficeToolbox/CreateSiteByHeader.aspx" /> 11: </CustomAction> 12: </Elements> .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Used Reflector to understand any special code behind createpage.aspx, and created a new for our purpose – CreateSiteByHeader.aspx. From there I quickly created a similar code behind, without all the fancy of Farm Config Wizard handling and dealt with alternate implementations of sealed classes! Goal was to create a professional looking and OOB-type experience. I also added Regex validation to ensure user types a valid domain name as header value. Below is the result…   Release @ Codeplex I’ve released to WSP on OfficeToolbox @ Codeplex, and you can download from here. Hope you find it useful… -- Sharad

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  • Developer Dashboard in SharePoint 2010

    - by jcortez
    Introducing the Developer Dashboard As a SharePoint developer (or IT Professional), how many times have you had the pleasure of figuring out why a particular page on your site is taking too long to render? I'm sure one of the techniques you have employed in troubleshooting is the process of elimination - removing individual web parts from the page hoping to identify which web part is misbehaving. One of the new features of SharePoint 2010 is the Developer Dashboard. This dashboard provides tracing and performance information that can be useful when you are trying to troubleshoot pages that are loading too slow. The Developer Dashboard is turned off by default and I'll go over 3 different ways to display it. Here is a screenshot of what the Developer Dashboard looks like when displayed at the bottom of the page:   You can see on the left side the different events that fired during the page processing pipeline and how long these events took. This is where you will see individual web parts being processed and how long it took to complete (obviously the kind of processing depends on what the web part does). On the right side you would see the different database calls issued through the SharePoint Object Model to process the page. You will notice that each of these database queries are actually a hyperlink and clicking on it displays a pop-up window that shows the actual SQL Query Text, the Call Stack that triggered the database call, and the IO statistics of that query. Enabling the Developer Dashboard Option 1: Managed Code   The Developer Dashboard is a farm-wide setting and the code above won't work if it is used within a web part hosted on any non-Central Admin site. The SPDeveloperDashboardLevel enum has three possible values: On, Off, and OnDemand. Setting it to On will always display the Developer Dashboard at the bottom of the page. Setting it Off will hide the Developer Dashboard. Setting it to OnDemand will add an icon at the top right corner of the page (see screenshot below) where a Site Collection Admin can toggle the display of the Developer Dashboard for a particular site collection. In my opinion, OnDemand is the best setting when troubleshooting a page or during development since a Site Collection Admin can turn it on or off and for a particular site only. The first cool thing about this is that the Site Collection Admin that turned it on will be the only one to see the Developer Dashboard output. Everyday users won't see the Developer Dashboard output even if it was turned on by a Site Collection Admin. If you need more flexibility on who gets to see the Developer Dashboard output, you can set the SPDeveloperDashboardSettings.RequiredPermissions to control which group of users will have the permission to see the output. Option 2: Using stsadm Using stsadm, you can run the following command to configure the Developer Dashboard: STSADM –o setproperty –pn developer-dashboard –pv OnDemand To successfully execute this command, be sure you that are running as a Farm Admin. Option 3: Using PowerShell For all scripts in SharePoint 2010, I prefer writing them as PowerShell scripts. Though the stsadm command is less verbose, the PowerShell equivalent is pretty straightforward and uses the SharePoint Object Model: You can of course parameterized the value that gets assigned to the DisplayLevel property so you can turn it On, Off or OnDemand depending on the parameter. Events and the Developer Dashboard  Now, don't assume that all the code inside your web part or page will show up in the Developer Dashboard complete with all the great troubleshooting information. Only a finite set of events are monitored by default (for a web part it will events in the base web part class). Let's say you have a click event that could take some time, for example a web service call. And you want to include troubleshooting information for this event in the Developer Dashboard. Enter SPMonitoredScope which is also a new feature in SharePoint 2010. In SharePoint 2010, everything is executed within a "Monitored Scope". And each scope has a set of "Monitors" that measures and counts calls and timings which appears in the Developer Dashboard. Below is an example on how to get your custom code to get included in the Developer Dashboard by wrapping it inside a new monitored scope: The code above would include your new scope "My long web service call" into the Developer Dashboard and would log the time it took to complete processing. In my opinion, wrapping your custom code in a SPMonitoredScope is a SharePoint development best practice since it provides you visibility and a better understanding on the performance of your components.

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  • MySQL 5.5 brings in new ways to authenticate users

    - by Georgi Kodinov
    Ever wanted to use your server's OS for authenticating MySQL users ? Or the corporate LDAP repository ? Unfortunately options like the above are plentiful nowadays. And providing hard-coded support for protocol X or service Y is not the best possible idea. MySQL 5.5 has taken the step into the right direction by providing an infrastructure allowing one to make the server understand different authentication protocols by creating a set of simple plugins (one for the client and one for the server). So now you can easily extend MySQL to search for and authenticate users in your favorite user directory. In fact the API supplied is so versatile that we took the possibility to re-design the current "native" authentication mechanism into a built-in always-on plugin ! OK, let me give you an example: Imagine we have a bunch of users defined in your OS, e.g. we have a user joro with his respective password. And we have a MySQL instance running on the same computer. It would not be unexpected to need to let joro access and/or modify MySQL data. The first step is to define him as a MySQL user. And there's a problem right there : MySQL's CREATE USER joro@localhost IDENTIFIED BY 'joros_password' statement needs a password. And this is a password in no way related to the password that joro have set up in the OS. What's worse : if joro changes his OS password this will in no way be reflected in MySQL. So he'll need to change his MySQL password in a separate step. Not very convenient, specially when you have a lot of users. This is a laborious setup for joro's DBA as well : he'll have to disable his access in both MySQL and the OS should he decides that joro's out of the "nice" list. Now mysql 5.5 to the rescue: Imagine that the smart DBA has created a MySQL server plugin that will check if the name of the user logging in is a valid and enabled OS name and if the password supplied to the mysql client matches the OS and has called this plugin 'auth_os'. Now all that's left to do is to define joro as a MySQL user that will be authenticated externally. This is done by the following command : CREATE USER 'joro'@'localhost' IDENTIFIED WITH 'auth_os'; Now joro can login to MySQL using his current OS password. Note : joro is still a valid MySQL user, so you can grant privileges to him just like you would for all other users. What's better: you can have users that authenticate using different mechanisms in the same server. So you can e.g. safely experiment with external authentication for selected users while keeping your current user base operational. What happens under the hood when joro logs in ? The server will find out by the user definition that it needs to use a non-default authentication and will ask the client to "switch" to using the appropriate client-side plugin (if of course the client is not already using it). If the client can't do this (e.g. because it's an old client or doesn't have the necessary plugin available) the server will reject the login. Otherwise the server will let the server-side plugin decide (while possibly talking to the client side plugin and the OS user directory) if this is a valid login or not. If it is the login process will continue as usual, while if it's not the login will get rejected. There's a lot more that MySQL 5.5 can do for you than just the simple case above. Stay tuned for more advanced use cases like mapping groups of external users to a single MySQL user (so you won't have to have 1-to-1 mapping between your external user directory and your mysql user repository) or ways to control the process as a DBA. Or you can simply skip ahead and read the relevant topics from MySQL's excellent online documentation. Or take a look at the example plugins in plugin/auth. Or take a look at the test suite in mysql-test/t/plugin_auth.test. Changelog entry: http://dev.mysql.com/doc/refman/5.5/en/news-5-5-7.html Primary new sections: Pluggable authentication Proxy users Client plugin C API functions Revised sections: New PROXY privilege New proxies_priv grant table Passwords might be external New external_user and proxy_user system variables New --default-auth and --plugin-dir mysql options New MYSQL_DEFAULT_AUTH and MYSQL_PLUGIN_DIR options for mysql_options() CREATE USER has IDENTIFIED WITH clause to specify auth plugin GRANT has PROXY privilege, IDENTIFIED WITH clause to specify auth plugin The data structure for writing client plugins

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  • The ASP.NET Daily Community Spotlight - How posts get there, and how to make it your Visual Studio Start Page

    - by Jon Galloway
    One really cool part of my job is selecting the articles for the Daily Community Spotlight, on the home page of the ASP.NET website. The spotlight highlights a new post about ASP.NET development every day from a member of the ASP.NET community. You can find it on the home page of the ASP.NET site, at http://asp.net These posts aren't automatically drawn from a pool of RSS feeds or anything - I pick a new post for each day of the year. How I pick the posts I have a few important selection criteria: Interesting to well rounded ASP.NET developers The ASP.NET website has a lot of material for all skill and experience levels, from download / get started to advanced. I try to select community spotlight posts to round that out with fresh and timely information that working ASP.NET developers can really use. Posts highlight solutions to common problems, clever projects and code that helps you leverage ASP.NET, and important announcements about things you can use today. As part of that, I try to mix between ASP.NET MVC, Web Forms, and Web Pages (a.k.a. WebMatrix). As a professional developer, I want to keep on top of all of my options for ASP.NET development, and the common platform base they all share generally means that good ASP.NET code is good ASP.NET code. Exposing new and non-Microsoft community members as much as possible The exercise of selecting good ASP.NET community posts every day of the year has made me think about what the community is. Given the choice, I'll always favor non-Microsoft employees, but since Microsoft often hires ASP.NET community members and MVP's (myself included), I really think that the ASP.NET community includes developers who are using and writing about ASP.NET, both inside and outside of Microsoft. I'm especially excited about the opportunity to highlight new and lesser known bloggers. Usually being featured on the ASP.NET Community Spotlight gives a pretty good traffic bump, and I love being able to both provide great content to the community and encourage lesser known community members by giving them some (much deserved) attention. Announcements only when they're useful to working developers - not marketing Some of the posts are announcements about new releases, such as Scott Hanselman's post on ASP.NET Universal Providers for Session, Memebership, and Roles. I include those when I think they're interesting and of immediate use to you on projects. I occasionally get asked to link to new content from a team at Microsoft; if it's useful and timely content I'll ask them to point me to a blog post by an actual person rather than a faceless team. How the posts are managed This feed used to be managed by an internal spreadsheet on a Sharepoint site, which was painful for a lot of reasons. I took a cue from Jon Udell, who uses of a public Delicious feed feed for his Elm City project, and we moved the management of these posts over to a Delicious feed as well. You can hear more about Jon's use of Delicious in Elm City in our Herding Code interview - still one of my favorite interviews. We ended up with a simpler scenario, but Note: I watched the Yahoo/Delicious news over the past year and was happy to see that Delicious was recently acquired by the founders of YouTube. I investigated several other Delicious competitors, but am happy with Delicious for now. My Delicious feed here: http://www.delicious.com/jon_galloway You can also browse through this past year's ASP.NET Community Spotlight posts using the (pretty cool) Delicious Browse Bar Submitting articles I'm always on the lookout for new articles to feature. The best way to get them to me is to share them via Delicious. It's pretty easy - sign up for an account, then you can add a post and share it to me. Alternatively, you can send them to me via Twitter (@jongalloway) or e-mail (). If you do e-mail me, it helps to include a short description and your full name so I can credit you. Way too many developer blogs don't include names and pictures; if I can't find them I can't feature the post. Subscribing to the Community Spotlight feed The Community Spotlight is available as an RSS feed, so you might want to subscribe to it: http://www.asp.net/rss/spotlight Setting the ASP.NET Community Spotlight feed as your Visual Studio start page If you're an ASP.NET developer, you might consider setting the ASP.NET Community Spotlight as the content for your Visual Studio Start Page. It's really easy - here's how to do it in Visual Studio 2010: Display the Visual Studio Start Page if it's not already showing (View / Start Page) Click on the Latest News tab and enter the following RSS URL: http://www.asp.net/rss/spotlight If you didn't previously have RSS feeds enabled for your start page, click the Enable RSS Feed button Now, every time you start up Visual Studio you'll see great content from members of the ASP.NET community: You can also configure - and disable, if you'd like - the Visual Studio start page in the Tools / Options / Environment / Startup dialog. Credits I'll do a follow-up highlighting some places I commonly find great content for the feed, but I'd like to specifically point out two of them: Elijah Manor posts a lot of great content, which is available in his Twitter feed at @elijahmanor, on his Delicious feed, and on a dedicated website - Web Dev Tweets Chris Alcock's The Morning Brew is a must-read blog which highlights each day's best blog posts across the .NET community. He's an absolute machine, and no matter how obscure the post I find, I can guarantee he'll find it as well if he hasn't already. Did I say must read?

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  • Database model for keeping track of likes/shares/comments on blog posts over time

    - by gage
    My goal is to keep track of the popular posts on different blog sites based on social network activity at any given time. The goal is not to simply get the most popular now, but instead find posts that are popular compared to other posts on the same blog. For example, I follow a tech blog, a sports blog, and a gossip blog. The tech blog gets waaay more readership than the other two blogs, so in raw numbers every post on the tech blog will always out number views on the other two. So lets say the average tech blog post gets 500 facebook likes and the other two get an average of 50 likes per post. Then when there is a sports blog post that has 200 fb likes and a gossip blog post with 300 while the tech blog posts today have 500 likes I want to highlight the sports and gossip blog posts (more likes than average vs tech blog with more # of likes but just average for the blog) The approach I am thinking of taking is to make an entry in a database for each blog post. Every x minutes (say every 15 minutes) I will check how many likes/shares/comments an entry has received on all the social networks (facebook, twitter, google+, linkeIn). So over time there will be a history of likes for each blog post, i.e post 1234 after 15 min: 10 fb likes, 4 tweets, 6 g+ after 30 min: 15 fb likes, 15 tweets, 10 g+ ... ... after 48 hours: 200 fb likes, 25 tweets, 15 g+ By keeping a history like this for each blog post I can know the average number of likes/shares/tweets at any give time interval. So for example the average number of fb likes for all blog posts 48hrs after posting is 50, and a particular post has 200 I can mark that as a popular post and feature/highlight it. A consideration in the design is to be able to easily query the values (likes/shares) for a specific time-frame, i.e. fb likes after 30min or tweets after 24 hrs in-order to compute averages with which to compare against (or should averages be stored in it's own table?) If this approach is flawed or could use improvement please let me know, but it is not my main question. My main question is what should a database scheme for storing this info look like? Assuming that the above approach is taken I am trying to figure out what a database schema for storing the likes over time would look like. I am brand new to databases, in doing some basic reading I see that it is advisable to make a 3NF database. I have come up with the following possible schema. Schema 1 DB Popular Posts Table: Post post_id ( primary key(pk) ) url title Table: Social Activity activity_id (pk) url (fk) type (i.e. facebook,twitter,g+) value timestamp This was my initial instinct (base on my very limited db knowledge). As far as I under stand this schema would be 3NF? I searched for designs of similar database model, and found this question on stackoverflow, http://stackoverflow.com/questions/11216080/data-structure-for-storing-height-and-weight-etc-over-time-for-multiple-users . The scenario in that question is similar (recording weight/height of users overtime). Taking the accepted answer for that question and applying it to my model results in something like: Schema 2 (same as above, but break down the social activity into 2 tables) DB Popular Posts Table: Post post_id (pk) url title Table: Social Measurement measurement_id (pk) post_id (fk) timestamp Table: Social stat stat_id (pk) measurement_id (fk) type (i.e. facebook,twitter,g+) value The advantage I see in schema 2 is that I will likely want to access all the values for a given time, i.e. when making a measurement at 30min after a post is published I will simultaneous check number of fb likes, fb shares, fb comments, tweets, g+, linkedIn. So with this schema it may be easier get get all stats for a measurement_id corresponding to a certain time, i.e. all social stats for post 1234 at time x. Another thought I had is since it doesn't make sense to compare number of fb likes with number of tweets or g+ shares, maybe it makes sense to separate each social measurement into it's own table? Schema 3 DB Popular Posts Table: Post post_id (pk) url title Table: fb_likes fb_like_id (pk) post_id (fk) timestamp value Table: fb_shares fb_shares_id (pk) post_id (fk) timestamp value Table: tweets tweets__id (pk) post_id (fk) timestamp value Table: google_plus google_plus_id (pk) post_id (fk) timestamp value As you can see I am generally lost/unsure of what approach to take. I'm sure this typical type of database problem (storing measurements overtime, i.e temperature statistic) that must have a common solution. Is there a design pattern/model for this, does it have a name? I tried searching for "database periodic data collection" or "database measurements over time" but didn't find anything specific. What would be an appropriate model to solve the needs of this problem?

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  • Windows Phone 7 development: Using isolated storage

    - by DigiMortal
    In my previous posting about Windows Phone 7 development I showed how to use WebBrowser control in Windows Phone 7. In this posting I make some other improvements to my blog reader application and I will show you how to use isolated storage to store information to phone. Why isolated storage? Isolated storage is place where your application can save its data and settings. The image on right (that I stole from MSDN library) shows you how application data store is organized. You have no other options to keep your files besides isolated storage because Windows Phone 7 does not allow you to save data directly to other file system locations. From MSDN: “Isolated storage enables managed applications to create and maintain local storage. The mobile architecture is similar to the Silverlight-based applications on Windows. All I/O operations are restricted to isolated storage and do not have direct access to the underlying operating system file system. Ultimately, this helps to provide security and prevents unauthorized access and data corruption.” Saving files from web to isolated storage I updated my RSS-reader so it reads RSS from web only if there in no local file with RSS. User can update RSS-file by clicking a button. Also file is created when application starts and there is no RSS-file. Why I am doing this? I want my application to be able to work also offline. As my code needs some more refactoring I provide it with some next postings about Windows Phone 7. If you want it sooner then please leave me a comment here. Here is the code for my RSS-downloader that downloads RSS-feed and saves it to isolated storage file calles rss.xml. public class RssDownloader {     private string _url;     private string _fileName;       public delegate void DownloadCompleteDelegate();     public event DownloadCompleteDelegate DownloadComplete;       public RssDownloader(string url, string fileName)     {         _url = url;         _fileName = fileName;     }       public void Download()     {         var request = (HttpWebRequest)WebRequest.Create(_url);         var result = (IAsyncResult)request.BeginGetResponse(ResponseCallback, request);            }       private void ResponseCallback(IAsyncResult result)     {         var request = (HttpWebRequest)result.AsyncState;         var response = request.EndGetResponse(result);           using(var stream = response.GetResponseStream())         using(var reader = new StreamReader(stream))         using(var appStorage = IsolatedStorageFile.GetUserStoreForApplication())         using(var file = appStorage.OpenFile("rss.xml", FileMode.OpenOrCreate))         using(var writer = new StreamWriter(file))         {             writer.Write(reader.ReadToEnd());         }           if (DownloadComplete != null)             DownloadComplete();     } } Of course I modified RSS-source for my application to use rss.xml file from isolated storage. As isolated storage files also base on streams we can use them everywhere where streams are expected. Reading isolated storage files As isolated storage files are opened as streams you can read them like usual files in your usual applications. The next code fragment shows you how to open file from isolated storage and how to read it using XmlReader. Previously I used response stream in same place. using(var appStorage = IsolatedStorageFile.GetUserStoreForApplication()) using(var file = appStorage.OpenFile("rss.xml", FileMode.Open)) {     var reader = XmlReader.Create(file);                      // more code } As you can see there is nothing complex. If you have worked with System.IO namespace objects then you will find isolated storage classes and methods to be very similar to these. Also mention that application storage and isolated storage files must be disposed after you are not using them anymore.

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  • Linux-Containers — Part 1: Overview

    - by Lenz Grimmer
    "Containers" by Jean-Pierre Martineau (CC BY-NC-SA 2.0). Linux Containers (LXC) provide a means to isolate individual services or applications as well as of a complete Linux operating system from other services running on the same host. To accomplish this, each container gets its own directory structure, network devices, IP addresses and process table. The processes running in other containers or the host system are not visible from inside a container. Additionally, Linux Containers allow for fine granular control of resources like RAM, CPU or disk I/O. Generally speaking, Linux Containers use a completely different approach than "classicial" virtualization technologies like KVM or Xen (on which Oracle VM Server for x86 is based on). An application running inside a container will be executed directly on the operating system kernel of the host system, shielded from all other running processes in a sandbox-like environment. This allows a very direct and fair distribution of CPU and I/O-resources. Linux containers can offer the best possible performance and several possibilities for managing and sharing the resources available. Similar to Containers (or Zones) on Oracle Solaris or FreeBSD jails, the same kernel version runs on the host as well as in the containers; it is not possible to run different Linux kernel versions or other operating systems like Microsoft Windows or Oracle Solaris for x86 inside a container. However, it is possible to run different Linux distribution versions (e.g. Fedora Linux in a container on top of an Oracle Linux host), provided it supports the version of the Linux kernel that runs on the host. This approach has one caveat, though - if any of the containers causes a kernel crash, it will bring down all other containers (and the host system) as well. For example, Oracle's Unbreakable Enterprise Kernel Release 2 (2.6.39) is supported for both Oracle Linux 5 and 6. This makes it possible to run Oracle Linux 5 and 6 container instances on top of an Oracle Linux 6 system. Since Linux Containers are fully implemented on the OS level (the Linux kernel), they can be easily combined with other virtualization technologies. It's certainly possible to set up Linux containers within a virtualized Linux instance that runs inside Oracle VM Server for Oracle VM Virtualbox. Some use cases for Linux Containers include: Consolidation of multiple separate Linux systems on one server: instances of Linux systems that are not performance-critical or only see sporadic use (e.g. a fax or print server or intranet services) do not necessarily need a dedicated server for their operations. These can easily be consolidated to run inside containers on a single server, to preserve energy and rack space. Running multiple instances of an application in parallel, e.g. for different users or customers. Each user receives his "own" application instance, with a defined level of service/performance. This prevents that one user's application could hog the entire system and ensures, that each user only has access to his own data set. It also helps to save main memory — if multiple instances of a same process are running, the Linux kernel can share memory pages that are identical and unchanged across all application instances. This also applies to shared libraries that applications may use, they are generally held in memory once and mapped to multiple processes. Quickly creating sandbox environments for development and testing purposes: containers that have been created and configured once can be archived as templates and can be duplicated (cloned) instantly on demand. After finishing the activity, the clone can safely be discarded. This allows to provide repeatable software builds and test environments, because the system will always be reset to its initial state for each run. Linux Containers also boot significantly faster than "classic" virtual machines, which can save a lot of time when running frequent build or test runs on applications. Safe execution of an individual application: if an application running inside a container has been compromised because of a security vulnerability, the host system and other containers remain unaffected. The potential damage can be minimized, analyzed and resolved directly from the host system. Note: Linux Containers on Oracle Linux 6 with the Unbreakable Enterprise Kernel Release 2 (2.6.39) are still marked as Technology Preview - their use is only recommended for testing and evaluation purposes. The Open-Source project "Linux Containers" (LXC) is driving the development of the technology behind this, which is based on the "Control Groups" (CGroups) and "Name Spaces" functionality of the Linux kernel. Oracle is actively involved in the Linux Containers development and contributes patches to the upstream LXC code base. Control Groups provide means to manage and monitor the allocation of resources for individual processes or process groups. Among other things, you can restrict the maximum amount of memory, CPU cycles as well as the disk and network throughput (in MB/s or IOP/s) that are available for an application. Name Spaces help to isolate process groups from each other, e.g. the visibility of other running processes or the exclusive access to a network device. It's also possible to restrict a process group's access and visibility of the entire file system hierarchy (similar to a classic "chroot" environment). CGroups and Name Spaces provide the foundation on which Linux containers are based on, but they can actually be used independently as well. A more detailed description of how Linux Containers can be created and managed on Oracle Linux will be explained in the second part of this article. Additional links related to Linux Containers: OTN Article: The Role of Oracle Solaris Zones and Linux Containers in a Virtualization Strategy Linux Containers on Wikipedia - Lenz Grimmer Follow me on: Personal Blog | Facebook | Twitter | Linux Blog |

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  • Searching for tasks with code – Executables and Event Handlers

    Searching packages or just enumerating through all tasks is not quite as straightforward as it may first appear, mainly because of the way you can nest tasks within other containers. You can see this illustrated in the sample package below where I have used several sequence containers and loops. To complicate this further all containers types, including packages and tasks, can have event handlers which can then support the full range of nested containers again. Towards the lower right, the task called SQL In FEL also has an event handler not shown, within which is another Execute SQL Task, so that makes a total of 6 Execute SQL Tasks 6 tasks spread across the package. In my previous post about such as adding a property expressionI kept it simple and just looked at tasks at the package level, but what if you wanted to find any or all tasks in a package? For this post I've written a console program that will search a package looking at all tasks no matter how deeply nested, and check to see if the name starts with "SQL". When it finds a matching task it writes out the hierarchy by name for that task, starting with the package and working down to the task itself. The output for our sample package is shown below, note it has found all 6 tasks, including the one on the OnPreExecute event of the SQL In FEL task TaskSearch v1.0.0.0 (1.0.0.0) Copyright (C) 2009 Konesans Ltd Processing File - C:\Projects\Alpha\Packages\MyPackage.dtsx MyPackage\FOR Counter Loop\SQL In Counter Loop MyPackage\SEQ For Each Loop Wrapper\FEL Simple Loop\SQL In FEL MyPackage\SEQ For Each Loop Wrapper\FEL Simple Loop\SQL In FEL\OnPreExecute\SQL On Pre Execute for FEL SQL Task MyPackage\SEQ Top Level\SEQ Nested Lvl 1\SEQ Nested Lvl 2\SQL In Nested Lvl 2 MyPackage\SEQ Top Level\SEQ Nested Lvl 1\SQL In Nested Lvl 1 #1 MyPackage\SEQ Top Level\SEQ Nested Lvl 1\SQL In Nested Lvl 1 #2 6 matching tasks found in package. The full project and code is available for download below, but first we can walk through the project to highlight the most important sections of code. This code has been abbreviated for this description, but is complete in the download. First of all we load the package, and then start by looking at the Executables for the package. // Load the package file Application application = new Application(); using (Package package = application.LoadPackage(filename, null)) { int matchCount = 0; // Look in the package's executables ProcessExecutables(package.Executables, ref matchCount); ... // // ... // Write out final count Console.WriteLine("{0} matching tasks found in package.", matchCount); } The ProcessExecutables method is a key method, as an executable could be described as the the highest level of a working functionality or container. There are several of types of executables, such as tasks, or sequence containers and loops. To know what to do next we need to work out what type of executable we are dealing with as the abbreviated version of method shows below. private static void ProcessExecutables(Executables executables, ref int matchCount) { foreach (Executable executable in executables) { TaskHost taskHost = executable as TaskHost; if (taskHost != null) { ProcessTaskHost(taskHost, ref matchCount); ProcessEventHandlers(taskHost.EventHandlers, ref matchCount); continue; } ... // // ... ForEachLoop forEachLoop = executable as ForEachLoop; if (forEachLoop != null) { ProcessExecutables(forEachLoop.Executables, ref matchCount); ProcessEventHandlers(forEachLoop.EventHandlers, ref matchCount); continue; } } } As you can see if the executable we find is a task we then call out to our ProcessTaskHost method. As with all of our executables a task can have event handlers which themselves contain more executables such as task and loops, so we also make a call out our ProcessEventHandlers method. The other types of executables such as loops can also have event handlers as well as executables. As shown with the example for the ForEachLoop we call the same ProcessExecutables and ProcessEventHandlers methods again to drill down into the hierarchy of objects that the package may contain. This code needs to explicitly check for each type of executable (TaskHost, Sequence, ForLoop and ForEachLoop) because whilst they all have an Executables property this is not from a common base class or interface. This example was just a simple find a task by its name, so ProcessTaskHost really just does that. We also get the hierarchy of objects so we can write out for information, obviously you can adapt this method to do something more interesting such as adding a property expression. private static void ProcessTaskHost(TaskHost taskHost, ref int matchCount) { if (taskHost == null) { return; } // Check if the task matches our match name if (taskHost.Name.StartsWith(TaskNameFilter, StringComparison.OrdinalIgnoreCase)) { // Build up the full object hierarchy of the task // so we can write it out for information StringBuilder path = new StringBuilder(); DtsContainer container = taskHost; while (container != null) { path.Insert(0, container.Name); container = container.Parent; if (container != null) { path.Insert(0, "\\"); } } // Write the task path // e.g. Package\Container\Event\Task Console.WriteLine(path); Console.WriteLine(); // Increment match counter for info matchCount++; } } Just for completeness, the other processing method we covered above is for event handlers, but really that just calls back to the executables. This same method is called in our main package method, but it was omitted for brevity here. private static void ProcessEventHandlers(DtsEventHandlers eventHandlers, ref int matchCount) { foreach (DtsEventHandler eventHandler in eventHandlers) { ProcessExecutables(eventHandler.Executables, ref matchCount); } } As hopefully the code demonstrates, executables (Microsoft.SqlServer.Dts.Runtime.Executable) are the workers, but within them you can nest more executables (except for task tasks).Executables themselves can have event handlers which can in turn hold more executables. I have tried to illustrate this highlight the relationships in the following diagram. Download Sample code project TaskSearch.zip (11KB)

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  • Form, function and complexity in rule processing

    - by Charles Young
    Tim Bass posted on ‘Orwellian Event Processing’. I was involved in a heated exchange in the comments, and he has more recently published a post entitled ‘Disadvantages of Rule-Based Systems (Part 1)’. Whatever the rights and wrongs of our exchange, it clearly failed to generate any agreement or understanding of our different positions. I don't particularly want to promote further argument of that kind, but I do want to take the opportunity of offering a different perspective on rule-processing and an explanation of my comments. For me, the ‘red rag’ lay in Tim’s claim that “...rules alone are highly inefficient for most classes of (not simple) problems” and a later paragraph that appears to equate the simplicity of form (‘IF-THEN-ELSE’) with simplicity of function.   It is not the first time Tim has expressed these views and not the first time I have responded to his assertions.   Indeed, Tim has a long history of commenting on the subject of complex event processing (CEP) and, less often, rule processing in ‘robust’ terms, often asserting that very many other people’s opinions on this subject are mistaken.   In turn, I am of the opinion that, certainly in terms of rule processing, which is an area in which I have a specific interest and knowledge, he is often mistaken. There is no simple answer to the fundamental question ‘what is a rule?’ We use the word in a very fluid fashion in English. Likewise, the term ‘rule processing’, as used widely in IT, is equally difficult to define simplistically. The best way to envisage the term is as a ‘centre of gravity’ within a wider domain. That domain contains many other ‘centres of gravity’, including CEP, statistical analytics, neural networks, natural language processing and so much more. Whole communities tend to gravitate towards and build themselves around some of these centres. The term 'rule processing' is associated with many different technology types, various software products, different architectural patterns, the functional capability of many applications and services, etc. There is considerable variation amongst these different technologies, techniques and products. Very broadly, a common theme is their ability to manage certain types of processing and problem solving through declarative, or semi-declarative, statements of propositional logic bound to action-based consequences. It is generally important to be able to decouple these statements from other parts of an overall system or architecture so that they can be managed and deployed independently.  As a centre of gravity, ‘rule processing’ is no island. It exists in the context of a domain of discourse that is, itself, highly interconnected and continuous.   Rule processing does not, for example, exist in splendid isolation to natural language processing.   On the contrary, an on-going theme of rule processing is to find better ways to express rules in natural language and map these to executable forms.   Rule processing does not exist in splendid isolation to CEP.   On the contrary, an event processing agent can reasonably be considered as a rule engine (a theme in ‘Power of Events’ by David Luckham).   Rule processing does not live in splendid isolation to statistical approaches such as Bayesian analytics. On the contrary, rule processing and statistical analytics are highly synergistic.   Rule processing does not even live in splendid isolation to neural networks. For example, significant research has centred on finding ways to translate trained nets into explicit rule sets in order to support forms of validation and facilitate insight into the knowledge stored in those nets. What about simplicity of form?   Many rule processing technologies do indeed use a very simple form (‘If...Then’, ‘When...Do’, etc.)   However, it is a fundamental mistake to equate simplicity of form with simplicity of function.   It is absolutely mistaken to suggest that simplicity of form is a barrier to the efficient handling of complexity.   There are countless real-world examples which serve to disprove that notion.   Indeed, simplicity of form is often the key to handling complexity. Does rule processing offer a ‘one size fits all’. No, of course not.   No serious commentator suggests it does.   Does the design and management of large knowledge bases, expressed as rules, become difficult?   Yes, it can do, but that is true of any large knowledge base, regardless of the form in which knowledge is expressed.   The measure of complexity is not a function of rule set size or rule form.  It tends to be correlated more strongly with the size of the ‘problem space’ (‘search space’) which is something quite different.   Analysis of the problem space and the algorithms we use to search through that space are, of course, the very things we use to derive objective measures of the complexity of a given problem. This is basic computer science and common practice. Sailing a Dreadnaught through the sea of information technology and lobbing shells at some of the islands we encounter along the way does no one any good.   Building bridges and causeways between islands so that the inhabitants can collaborate in open discourse offers hope of real progress.

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