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  • .tex file remains in use by process when batch file is triggered by .Rnw Sweave processing.

    - by drknexus
    This is a pretty specialized question. I'm using the Eclipse IDE in a Windows XP environment with the StatET plug-in so I can write R code as an R/Sweave document. This produces a .tex file that is then post processed by pdflatex.exe. When I create the file as normal everything works great (except maybe my file named russfnc2.Rnw seems to result in russfnc.pdf even though pdflatex.exe on the console window correctly says that the output is being writen to russfnc2.pdf). The big problem is when I trigger a batch file from within my Rnw code. My goal here is to spawn a side process that waits for the PDF to be made and uploads it to the server. So the Rnw contains: if(file.exists("rsp.finalize.bat")) {system("rsp.finalize.bat",wait=FALSE,invisible=FALSE)} The batch file calls Rterm.exe to run a script: setwd("C:/theprojectdirectory") while(!file.exists("russfnc.pdf")) { Sys.sleep(1) } Sys.sleep(60) At the end of that script, I use a shell call to launch psftp.exe and upload the files. All of this works fine, when I use my Eclipse profile to trigger Sweave... that is unless I have that batch file at the end of the .Rnw. When it is located there, I get the error message pdflatex.exe: Permission denied: c:\thepath\thetexfile.tex. After that, the .tex file (as far as XP is concerned) is in use by another process and I have to reboot in order to delete it (and, of course, the pdf is not made). If I manually trigger the batch file after pdflatex.exe has done its things, everything works fine. How can I make this work correctly using the tools I'm familiar with vis., R and Dos-style batch files? I'm not sure if this is a SuperUser question or a StackOverflow question, so I'm starting here.

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  • Access Denied on Some Subfolders/Files Within a Share

    - by Tim
    First thing this morning, I find that users on one of our share drives are all getting "access denied". I tried the same drive and also received "access denied" as a Domain Admin. Previous to this, all specified users and admins could get access. I checked share permissions I checked NTFS permissions I temporarily made both types of permissions read/write to "Everyone" -- This worked for one user It turns out that this is occurring for only some files/folders. When I try to manually alter the share of that single share, it can't be shared, access denied. xcacls also gets access denied rebooted the server (not a big deal - this is a smallish company). Does anybody have any insight, my google-fu is coming up blank. Thanks. EDIT: More info, I just ran AccessEnum. There were a lot of "access denied", but I noticed the pattern that all of the access denied had a parent with an owner of "???". When I look at the properties, the "Unable to display owner" message is in the box and I can only make my user account the owner. I can then share the individual file/folder, but it doesn't seem to propogate down to subfolders/files.

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  • ASP.NET Session State SQL Server 2008 R2 Freezes with High CPU Usage

    - by jtseng
    Our ASP.Net website uses SQL Server as the session state provider. We currently host the database on SQL Server 2005 since it does not play well on 2008 R2. We would like to know why, and how to fix it. hardware setup Our current session state server has SQL Server 2005 with the files hosted on a single local disk. It is one of our oldest servers since it has served us well, and we never felt the need to upgrade it. The database is about 2 GB holding 6000 sessions. (The sessions are a little big, but we need it.) We have another server with SQL Server 2008 R2 with a much faster CPU, much more RAM, and a much faster hard disk. situation One day, we have a huge surge in traffic. The transaction log growth on SQL Server freezes the server for 10's of seconds, allowing only a few requests through in minutes. So we load up the new server with ASPState with very large data and log files and point all of our applications to the new server. It chugs along fine for about 5 minutes, and then the CPU usage jumps up to 50% of the 16 cores that Standard Edition can use and freezes for 10's of seconds at a time. The files do not record any autogrowth events. The disk queue is nice and low. RAM usage is low. CPU usage on our old server has never been higher than 5%. What happened on the new server? Alternatively, I would like to hear success stories with ASP.NET session state server running on SQL Server 2008 R2 with an average write load of 30MB/sec with bursts up to 200MB/sec.

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  • Few questions about a good projector on my PC and tv?

    - by jasondavis
    I have always wanted a projector for my tv, satelite, cable, and even PC in a spare bedroom. Well it's more of a home office that I spend most my time in and the catch here is it is a small room. Room is only the standard 8foot tall. Room is about 13 feet wide on the wall where I would like to mount the project and the wall where the screen would be for it. So only about 13 feet away from projector to screen. I would like to know... 1) From experience or knowledge what would be a good projector I could hook up to my satelite box and also my PC? Cheaper is better in this case but I would still like the best image for my buck and something reliable. There is no sunlight in the room either to worry about. 2) From that distance of about 12-13 feet away, how big of a clear picture could I expect? 3) What kind of cables would I need to purchase and run through my attic to my cable/satelite receiver box as well as my PC? 4) These cables in question 3 would most likely need to be a good 15-20feet in length to reach, would I need anything special for that to work at those distances?

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  • My home box as my own host?

    - by Majid
    Hi all, I have a 512 kb/s DSL service at home. I do not have a static IP but I can get one if I pay some extra to my ISP. Now, if I get the static IP, can I make my home box act as my internet host? What else do I need? Thanks P.S. I know that if at all possible, the site I make available this way might be slow, that is alright, my question is if it is possible at all. Edit: I need this for very small traffic. I am a php developer and for my projects I am often asked to provide a demo. I currently use a free hosting for this purpose but it is down most of the time and support is non-existent. So I thought to set-up my home computer as my test server. With this please note that: I will only occasionally have 'visitors' and that will be one or possibly two visitors at any time. These demos, are to showcase functionality, so no big images are served and page views will normally generate under 100KB of traffic.

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  • How do I prevent spawning of zombie-like apache2 processes on Dreamhost VPS?

    - by Jonathan Hayward
    I have had a website for months or longer on a DreamHost VPS, and I have had vague memories on, in initial setup, having to turn off some customized Apache under /dh to get a standard Apache 2.x to work with. Things have been going along on an even keel, when I started making some changes lately and I found that when I tried to bounce Apache (/usr/sbin/apachectl restart), it couldn't bind to port 80, and my site had been converted from a big literature site to a small parking site. I tried to see what was listening on 80, and it was a DreamHost-customized Apache that had spawned. I killed all of them, restarted Apache, and changed the parent directory under /dh to mode 000. That was a day or two ago. I was bouncing Apache again in trying to get a new site to load under HTTPS, and I found that once again DreamHost's apache had spawned, from the directory I set to mode 000, and once again converted my site to a parking page. I renamed the directory, but I am very skeptical of whether I have permanently killed the DreamHost-customized Apache. Besides duct tape options like a crontab to kill and delete each minute, how can I permanently turn off the Apache processes that are spawning from a location under /dh and interfering with standard Apache? What should I be doing that I am not? Can DreamHost's technical support stop the interference? Thanks,

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  • How to connect a Win XP PC and Win 7 PC with a Linksys WRT54G Router to a PPPOE connection ?

    - by ChristianM
    I have two PCs and a WRT56G Router. My provider is a PPPOE connection (username and password). I can connect my Windows 7 easily. Even if I choose Auto or PPPOE on the router's configuration. Maybe because this one had the connection in the first place with the username and password set up. But I can't connect the Windows XP PC. Actually it does connect in a way, but it receives and sents just a few packages. I can actually see in My Network Places how many packages does the Gateway make and it's a big difference. And it won't open any page. How should I set up the router so I can give enough bandwith to the Windows XP PC ? I've seen another problem that I forgot to mention. The router can't connect with the pppoe settings. I don't know why, but with Auto DHCP setting and my Windows 7 connected with pppoe settings works. EDIT2: I've installed Win 7 on the other PC so I won't have any problem of compatibility betwen them. But I still can't connect the router with PPPOE settings to the internet. It looks like this: http://img641.imageshack.us/img641/9780/capturefba.png If you need any other screens or info, please tell me.

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  • Including email, IMs, configs, etc. in documentation or notes

    - by Jason Antman
    The shop I work in is pretty laid-back. We're on a documentation kick, only because historically we've been very bad with it. We do a lot of our brainstorming in face-to-face meetings, and also do a lot of communication via IM in addition to email. While I'm usually pretty good about documentation and keeping copious lab notes, I just finished a build of a host and spent hours searching through IMs, emails, files on my workstation, etc. to pull out anything I missed in my lab notes, which formed a large amount of the basis for the internal documentation. Does anyone have any thoughts on, aside from manually saving things to a project directory, managing various data sources (especially email and IM) and tracking them on project basis? Ideally, I'd like an easy way to put copies of emails, IM logs, etc. into a project-specific directory on my workstation and then just have a cron job that syncs that up with a shared folder. This isn't really a candidate for anything more advanced, as the bulk of the data will be copies of configs, code, etc. Here are the big restrictions: Email is via a centralized Zimbra install, so nothing can happen server-side. My workstation is Linux. Aside from writing Pidgin and Thunderbird plugins that let me tag chats and emails as belonging to a project, and then copy them to the appropriate place... any thoughts? Suggestions? Thanks, Jason

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  • 10 GigE interfaces limits single connection throughput to 1 Gb on a ProCurve 4208vl

    - by wazoox
    The setup is as follow : 3 Linux servers with Intel CX4 10 GigE controllers and an X-Serve with a Myricom 10 GigE CX4 controller are connected to a ProCurve 4208vl switch, with a myriad of other machines connected through good ol' 1000 base-T. The interfaces are actually set up as 10 Gig, according to both the switch monitoring interface and the servers (ethtool, etc). However a single connection between two 10 GigE equipped machines through the switch is limited to exactly 1Gb. If I connect two of the 10 GigE machines directly with a CX4 cable, netperf reports the link bandwidth as 9000 Mb/s. NFS achieves about 550 MB/s transfers. But when I'm using the switch, the connection tops at 950 Mb/s through netperf and 110 MB/s with NFS. When I open several connections from 3 of the machines to the 4th, I get 350 MB/s of NFS transfer speed. So each individual 10 GigE ports actually can reach much more than 1 Gb, but individual connections are strictly limited to 1 Gb. Conclusion : the 10 GigE connection through the switch behaves exactly like a trunk of 10 1 Gb connections. That doesn't make any sense to me, unless HP planned these ports only for cascading switches or strictly for many-clients-to-single-server connection. Unfortunately this is NOT the envisioned setup, we need big throughput from machine to machine. Is this a not-so-known (or carefully hidden...) limitation of this type of switch? Should I suggest seppuku to the HP representative? Does anyone have any idea on how to enable a proper behaviour ? I upgraded for an hefty price from bonded 1Gb links to 10 GigE and see exactly ZERO gain! That's absolutely unacceptable.

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  • Python not Working in Vim

    - by jdg
    I have a new install of VIM from the automatic windows installer: gvim73_46.exe I have Python 2.7 (32 bit) installed. If I open gvim, and type: :set python? I get E518: Unknown option. If I try typing: :python 'hello' Vim crashes. What could be wrong? Here are the contents of :version in case they are helpful, although python is installed, and it is using Python 2.7. I also checked, and C:\Windows\System32\python27.dll is where it should be... I am really lost here. Does anyone have any ideas as to what is going wrong? VIM - Vi IMproved 7.3 (2010 Aug 15, compiled Oct 27 2010 17:59:02) MS-Windows 32-bit GUI version with OLE support Included patches: 1-46 Compiled by Bram@KIBAALE Big version with GUI. Features included (+) or not (-): +arabic +autocmd +balloon_eval +browse ++builtin_terms +byte_offset +cindent +clientserver +clipboard +cmdline_compl +cmdline_hist +cmdline_info +comments +conceal +cryptv +cscope +cursorbind +cursorshape +dialog_con_gui +diff +digraphs -dnd -ebcdic +emacs_tags +eval +ex_extra +extra_search +farsi +file_in_path +find_in_path +float +folding -footer +gettext/dyn -hangul_input +iconv/dyn +insert_expand +jumplist +keymap +langmap +libcall +linebreak +lispindent +listcmds +localmap -lua +menu +mksession +modify_fname +mouse +mouseshape +multi_byte_ime/dyn +multi_lang -mzscheme +netbeans_intg +ole -osfiletype +path_extra +perl/dyn +persistent_undo -postscript +printer -profile +python/dyn +python3/dyn +quickfix +reltime +rightleft +ruby/dyn +scrollbind +signs +smartindent -sniff +startuptime +statusline -sun_workshop +syntax +tag_binary +tag_old_static -tag_any_white +tcl/dyn -tgetent -termresponse +textobjects +title +toolbar +user_commands +vertsplit +virtualedit +visual +visualextra +viminfo +vreplace +wildignore +wildmenu +windows +writebackup -xfontset -xim -xterm_save +xpm_w32 system vimrc file: "$VIM\vimrc" user vimrc file: "$HOME_vimrc" 2nd user vimrc file: "$VIM_vimrc" user exrc file: "$HOME_exrc" 2nd user exrc file: "$VIM_exrc" system gvimrc file: "$VIM\gvimrc" user gvimrc file: "$HOME_gvimrc" 2nd user gvimrc file: "$VIM_gvimrc" system menu file: "$VIMRUNTIME\menu.vim" Compilation: cl -c /W3 /nologo -I. -Iproto -DHAVE_PATHDEF -DWIN32 -DFEAT_CSCOPE -DFEAT_NETBEANS_INTG -DFEAT_XPM_W32 -DWINVER=0x0400 -D_WIN32_WINNT=0x0400 /Fo.\ObjGOLYHTR/ /Ox /GL -DNDEBUG /Zl /MT -DFEAT_OLE -DFEAT_MBYTE_IME -DDYNAMIC_IME -DFEAT_GUI_W32 -DDYNAMIC_ICONV -DDYNAMIC_GETTEXT -DFEAT_TCL -DDYNAMIC_TCL -DDYNAMIC_TCL_DLL=\"tcl83.dll\" -DDYNAMIC_TCL_VER=\"8.3\" -DFEAT_PYTHON -DDYNAMIC_PYTHON -DDYNAMIC_PYTHON_DLL=\"python27.dll\" -DFEAT_PYTHON3 -DDYNAMIC_PYTHON3 -DDYNAMIC_PYTHON3_DLL=\"python31.dll\" -DFEAT_PERL -DDYNAMIC_PERL -DDYNAMIC_PERL_DLL=\"perl512.dll\" -DFEAT_RUBY -DDYNAMIC_RUBY -DDYNAMIC_RUBY_VER=191 -DDYNAMIC_RUBY_DLL=\"msvcrt-ruby191.dll\" -DFEAT_BIG /Fd.\ObjGOLYHTR/ /Zi Linking: link /RELEASE /nologo /subsystem:windows /LTCG:STATUS oldnames.lib kernel32.lib advapi32.lib shell32.lib gdi32.lib comdlg32.lib ole32.lib uuid.lib /machine:i386 /nodefaultlib gdi32.lib version.lib winspool.lib comctl32.lib advapi32.lib shell32.lib /machine:i386 /nodefaultlib libcmt.lib oleaut32.lib user32.lib /nodefaultlib:python27.lib /nodefaultlib:python31.lib e:\tcl\lib\tclstub83.lib WSock32.lib e:\xpm\lib\libXpm.lib /PDB:gvim.pdb -debug

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  • Reconnecting OST with Exchange

    - by syrenity
    Hi. I have a quite big problem with customer's MS Exchange. The server got it's disk filled about 2 weeks ago, so it's currently offline. They plan to upgrade it, but not in hurry, as they use it mainly for OWA and back-up - the mails exchange is done via SMTP and POP3. Trying to diagnose some problem today, one of the users has (following the ISP instructions), removed the Exchange account from Outlook, which essentially left the OST orphaned. The user naturally didn't move the emails or any other data to the Archive / PST before, so these emails located on the OST only. So currently I'm trying to figure out how to restore them. There are 2 options: 1) Make the user buy some tool to convert them to PST, and import as archive / main Outlok file? 2) Reconnect the Outlook to Exchange (once it up), let it sync the old server content, then shutdown Outlook and replace the new OST with the old one, start Outlook again in offline mode and move these files to archive. 3) Any other method? Can someone advice what would be the best approach here? The used versions are Outlook 2007 and Exchange 2003. Thanks!

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  • Most scalable way of serving a small set of static HTTP content

    - by Ekevoo
    The story: Hi guys. I'm among the people responsible for serving the results of the most anticipated (by number of people participating) annual entrance exam in my state. As such, when our results are published, the interest is overwhelming. In the past we delegated the responsibility of serving the results to the media, but that spoils a little the officialness of these results. This year we went with a little (long overdue) experiment of using lighttpd instead of Apache as well as other physical network optimizations I wasn't directly involved with. The results were very satisfactory. The server didn't choke even once, nor we saw any of the usual Twitter complaints on unavailability and/or slowness that were previously common. However, because we still delegated the first publication of the results to the media I'm still not 100% sure we can handle the load of actually publishing the results first. The question: Now because these files are like 14MB in total and a true lightweight Linux distribution isn't that big either, I'm thinking: what if next year we run full RAMdrive? Is there any? Is that useful? Is that worth it for a team that uses Debian almost exclusively? Are there other optimizations that I should be focusing on instead?

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  • FTP Server with advanced features

    - by Nikolas Sakic
    Hi, We supply zone-files to our customers. Some zone files are big about 300MB and some are quite small, maybe like 1MB. We had this issue that someone setup a script to continually download the file. Imagine downloading 300MB file a few hundred times a day. Since, we don't have packet-shaper to throttle the traffic, we need to upgrade ftp server and use add-on modules to limit the download somehow. We currently use proftpd server. Also note that there are different users for different domains - say, if you want to download zone file for .INFO domain, then you use a particular user. That user can't download any other zone's file. This is what we are looking for: Have maximum of 400MB download per user per day. Or even have different download limit for different users per day. Have one connection per user at any time. Max # of connection (non-simultaneous) per user per day is 5. Anyone trying to exceed that gets banned for 24 hours. Has anyone used FTP server with similar restrictions above? Does anyone have any ideas where I can start? Any help would be appreciated. Thanks. -N

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  • Windows 7 doesn't start anymore

    - by martani_net
    Hi, I've experienced some BSOD on windows 7 RC, and some freezing when startup, but today was big surprise, it doesn't start anymore. I tried to start on safe mode and no results too, it shows the starting animation, then a blue screen for less than a second and turns off immediately. The only thing I remember did today is update flash player under Firefox, then chrome stopped working even after logging off, and once restarting, it doesn't start anymore. Anyone experienced the same issue? any hints? [EDIT 3] Solved : Windows 7 have a very smart repair strategy, it works automatically, and it tried every possible fix, what fixed my problem was the system restore to a previous date, all this happened automatically. [EDIT2] these are the last lines in the ntbtlog.txt file Did not load driver \SystemRoot\System32\drivers\vga.sys Loaded driver \SystemRoot\System32\Drivers\NDProxy.SYS Did not load driver \SystemRoot\System32\Drivers\NDProxy.SYS Did not load driver \SystemRoot\System32\Drivers\NDProxy.SYS Did not load driver \SystemRoot\System32\Drivers\NDProxy.SYS Did not load driver \SystemRoot\System32\Drivers\NDProxy.SYS Loaded driver \SystemRoot\system32\drivers\CHDRT32.sys Loaded driver \SystemRoot\system32\DRIVERS\VSTAZL3.SYS Loaded driver \SystemRoot\system32\DRIVERS\VSTDPV3.SYS Loaded driver \SystemRoot\system32\DRIVERS\VSTCNXT3.SYS Loaded driver \SystemRoot\system32\drivers\modem.sys Loaded driver \SystemRoot\system32\DRIVERS\usbccgp.sys Loaded driver \SystemRoot\System32\Drivers\usbvideo.sys [edit] this is the BSOD I get : http://twitpic.com/i87cx Thank you.

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  • How to set up a easy-to-use proxy for the whole system with WinXP client and server?

    - by Pekka
    I am working together intensively with a colleague on the Canary Islands. We speak through live messenger and work together using a RDP software. She has frequent problems with connections to certain big-name and small-name sites (amongst others live.com, google.com, gmx.de) very likely to be caused by the spanish provider (the connections simply time out, this has been going on for weeks already). I have been thinking about setting up my computer as a proxy to make these connections work. I have a DSL connection and am behind a NAT capable router that I control. Does anybody know a simple, "one-click" way to transport ALL network traffic through a remote proxy? Without having to set proxy settings for each application that uses the internet? VPN is not an option, because I am behind a firewall that supports protocol 47 and such, but I have never succeeded in getting an incoming VPN connection to work. I can however redirect normal traffic using NAT. A VPN solution that does not need strange protocols would also be an option.

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  • Network speed between a VM and another machine which is not residing on the same host, is 11MB/s at most

    - by Henno
    Problem Network speed between a VM and another machine which is not residing on the same host, is 11MB/s at most. Topology Facts ESXi5 version is 5.0.0.504890 VM has the latest Vmware Tools installed VM is using E1000 network driver Physical box has Win Srv 2008 R2 as the OS CrystalDiskMark says the drive on physical box can read/write 100MB/s vCenter is another vm on esx both vm and physical box are showing 1Gbps link speed Configuration Networking shows vmnic0 as 1000 Full NTttcp is a client/server tool from Microsoft for measuring pure network throughput Here's what I've done so far: Test1: VM is running Filezilla FTP Server (default settings, one user account made) Physical box is running Filezilla FTP Client (default settings) Physical box is uploading a big file to FTP server Transfer speed (as observed by Windows Task Manager on both machines): ~11MB/s (bad) Physical box is downloading that file from FTP server Transfer speed (as observed by Windows Task Manager on both machines): still ~11MB/s (bad) Could it be disk performance issue? Test2: Physical box is running ntttcpr.exe -a 6 -m 6,0,VM_IP_ADDRESS VM is running ntttcps.exe -a 6 -m 6,0,PHY_BOX_IP_ADDRESS Transfer speed (as observed by Windows Task Manager on both machines): ~11MB/s (bad) Could it be switch performance issue? Test3: physical box is running vSphere Client I open Summary Storage datastore Browse Datastore... from physical box and upload a file to datastore Transfer speed (as observed by Windows Task Manager on physical box): ~26-36MB/s (good) Could it be a vm specific issue? Test4: Installed ntttcp to another vm on the same esx server Measured network performance between vms on the same esx server with NTttcp Transfer speed (as observed by Windows Task Manager on physical box): ~90-120MB/s (excellent :) Test5: I have another esx server on the same site, connecting to the same datastore and same switch. Those two ESX servers have both 2 NICs. One NIC goes to switch while the other goes directly to the other ESX server. vMotioned one of the testing vms off to the other ESX host Measured network performance between vms on different esx servers with NTttcp Transfer speed (as observed by Windows Task Manager on physical box): ~11MB/s (bad) While I'm aware of these: ESXi 4.1 slow file transfer ESXi 5 network performance is slow Debian Etch and ESXi slow network speeds VMWare ESXi slow file copy to guest they did not help (or I must have been missed something)

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  • Is Cherokee (probably) the best static content server for beginner sysadmins?

    - by Bad Learner
    I have read the pros and cons of most of the popular web servers and have come to a conclusion that Apache would (probably) be the best web server for serving dynamic content - - no wonder YouTube, Flickr and Facbook, among many others, use it. I do not know if that C10K problem applies to Apache even when serving dynamic content only, but I think any web server used to serve dynamic content needs some good tweaking for optimized performance, and the fact that nothing beats Apache when it comes to documentation, resources and support on the web, I think should will go with Apache for dynamic content. That apart, the confusion begins when it comes to choosing web servers for static content (including streaming videos). I see that Nginx, Cherokee and Lighttpd are among the best (I am not considering non-open source or non-linux stuff here). So, which too choose? I know one cannot go wrong with any of the three (Nginx, Cherokee, Lighttpd). Lighttpd's development has evidently gotten slower than it was a good time ago. The documentation is pretty good for all the three, and hopefully, so are the resources (knowledge of these among the users of Stackoverflow/Serverfault sites, the web etc). Precisely, and noting point [2] and [3], if I am not wrong, I should either go with Nginx or Cherokee. I would love to see someone clarify these... is Cherokee just as fast (mb/s), performant (connections/s), and reliable (think downtime/restarting server) as Nginx for serving static content and load balancing, for small, medium to large (and really large) websites and applications? (Think, the size of YouTube, Apache or Facebook.) if the answer for the Q above is a big "hell, yes!" then, I should probably prefer Cherokee, right? Because, since I am a beginner, it would a lot easier to setup Cherokee as it has a graphical admin user interface + really good documentation. Yes? I could be wrong, I could be right. I put down what I know so that you can offer most relevant advise. Pardon if anything I've said is offensive.

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  • What is the peak theoretical WiFi G user density? [closed]

    - by Bigbio2002
    I've seen a few WiFi capacity planning questions, and this one is related, but hopefully different enough not to be closed. Also, this is related specifically to 802.11g, but a similar question could be made for N. In order to squeeze more WiFi users into a space, the transmit power on the APs need to be reduced and the APs squeezed closer together. My question is, how far can you practically take this before the network becomes unusable? There will come a point where the transmit power is so weak that nobody will actually be able to pick up a connection, or be constantly roaming to/from APs spaced a few feet apart as they walk around. There are also only 3 available channels to use as well, which is a factor to consider. After determining the peak AP density, then multiply by users-per-AP, which should be easier to find out. After factoring all of this in and running some back-of-the-envelope calculations, I'd like to be able to get a figure of "XX users per 10ft^2" or something. This can be considered the physical limit of WiFi, and will keep people from asking about getting 3,000 people in a ballroom conference on WiFi. Can anyone with WiFi experience chime in, or better yet, provide some calculations for a more accurate figure? Assumptions: Let's assume an ideal environment with no reflection (think of a big, square, open room, with the APs spaced out on a plane), APs are placed on the ceiling so humans won't absorb the waves, and the only interference are from the APs themselves and the devices. As for what devices specifically, that's irrelevant for the first point of the question (AP density, so only channel and transmit power should matter). User experience: Wikipedia states that Wireless G has about 22Mbps maximum effective throughput, or about 2.75MB/s. For the purpose of this question, anything below 100KB/s per user can be deemed to be a poor user experience. As for roaming, I'll assume the user is standing in the same place, so hopefully that will be a non-issue.

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  • vim coloring for git

    - by kelloti
    I'm on Windows and my vim loads with a terrible colorscheme with vim. The message is blue on black (so I can't see what I'm typing). I need to change the colorscheme, but :colorscheme slate doesn't do anything. :version vim - vi improved 7.3 (2010 aug 15, compiled oct 27 2010 17:51:38) ms-windows 32-bit console version included patches: 1-46 compiled by bram@kibaale big version without gui. features included (+) or not (-): +arabic +autocmd -balloon_eval -browse ++builtin_terms +byte_offset +cindent +clientserver +clipboard +cmdline_compl +cmdline_hist +cmdline_info +comments +conceal +cryptv +cscope +cursorbind +cursorshape +dialog_con +diff +digraphs -dnd -ebcdic +emacs_tags +eval +ex_extra +extra_search +farsi +file_in_path +find_in_path +float +folding -footer +gettext/dyn -hangul_input +iconv/dyn +insert_expand +jumplist +keymap +langmap +libcall +linebreak +lispindent +listcmds +localmap -lua +menu +mksession +modify_fname +mouse -mouseshape +multi_byte +multi_lang -mzscheme -netbeans_intg -osfiletype +path_extra -perl +persistent_undo -postscript +printer -profile -python -python3 +quickfix +reltime +rightleft -ruby +scrollbind +signs +smartindent -sniff +startuptime +statusline -sun_workshop +syntax +tag_binary +tag_old_static -tag_any_white -tcl -tgetent -termresponse +textobjects +title -toolbar +user_commands +vertsplit +virtualedit +visual +visualextra +viminfo +vreplace +wildignore +wildmenu +windows +writebackup -xfontset -xim -xterm_save -xpm_w32 system vimrc file: "$vim\vimrc" user vimrc file: "$home\_vimrc" 2nd user vimrc file: "$vim\_vimrc" user exrc file: "$home\_exrc" 2nd user exrc file: "$vim\_exrc" compilation: cl -c /w3 /nologo -i. -iproto -dhave_pathdef -dwin32 -dfeat_cscope -dwinver=0x0400 -d_win32_winnt=0x0400 /fo.\objc/ /ox /gl -dndebug /zl /mt -ddynamic_iconv -ddynamic_gettext -dfeat_big /fd.\objc/ /zi linking: link /release /nologo /subsystem:console /ltcg:status oldnames.lib kernel32.lib advapi32.lib shell32.lib gdi32.lib comdlg32.lib ole32.lib uuid.lib /machine:i386 /nodefaultlib libcmt.lib user32.lib /pdb:vim.pdb -debug My $HOME\_vimrc looks like colorscheme slate syn on set shiftwidth=2 set tabstop=2 and my $VIM\vimrc is the stock vimrc that comes with the Windows Vim distribution. How do I change my console Vim colorscheme? Especially for Git commits.

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  • Detecting login credentials abuse

    Greetings. I am the webmaster for a small, growing industrial association. Soon, I will have to implement a restricted, members-only section for the website. The problem is that our organization membership both includes big companies as well as amateur “clubs” (it's a relatively new industry…). It is clear that those clubs will share the login ID they will use to log onto our website. The problem is to detect whether one of their members will share the login credentials with people who would not normally supposed to be accessing the website (there is no objection for such a club to have all it’s members get on the website). I have thought about logging along with each sign-on the IP address as well as the OS and the browser used; if the OS/Browser stays constant and there are no more than, say, 10 different IP addresses, the account is clearly used by very few different computers. But if there are 50 OS/Browser combination and 150 different IPs, the credentials have obviously been disseminated far, and there would be then cause for action, such as modifying the password. Of course, it is extremely annoying when your password is being unilaterally changed. So, for this problem, I thought about allowing the “clubs” to manage their own list of sub-accounts, and therefore if abuse is suspected, the user responsible would be easily pinned-down, and this “sub-member” alone would face the annoyance of a password change. Question: What potential problems would anyone see with such an approach?

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  • Backup Exec tape rotation guidelines

    - by HannesFostie
    Hi We use Backup Exec to take care of our backups for our data server, exchange server, and one more set of systems. Each of these 3 is being done on a separate "set" of tapes. Our goal is to be able to roll back a full 2 weeks, with 1 full backup each weekend and differential/incremental backups in between (the difference between the two in our case isn't very big, because the employees mostly use a very similar set of files throughout the week). While playing around with the settings on how to achieve this, we set the time for BE to keep the full backup to 14 days, but because we have too much data this would require manual intervention each time to erase a certain tape and use that. What I would like to know is what kind of guidelines, tricks, tips and general "stuff to think about" you keep in mind when designing your backup schedule. The type of backups (full/diff/incr) isn't of that much importance in our case as it's more or less set in stone. Made this community wiki as it's not a very specific question. Thanks in advance!

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  • Application for time and project management

    - by user10826
    I want to improve the way I organize my projects/tasks/schedule What I do now is: keep an excel sheet with the name of the most important tasks/projects, I look at it at the beginning of each day and decide the ones I will focus on on iCal I write down events for each day, or for a concrete time (13 to 14 hours). I set up each day the tasks I want to accomlish, and allocate them hours I use Things (culture code) to keep info about tasks and projects not very important and which are not time allocated yet (GTD name = someday) I use Mail on Mac and create folders for the mails I want to process with the name of the different projects I save the main info for each project on freemind maps My system works well at the moment but it is pretty complicated to use. I want to make it better and I am looking for something with these requirements: must be 100% offline accessable it should use as less programs/resources as possible, ideally just one program should be able to manage all my info I can use the GTD methodology mixed with priorities and I can allocate each task converted to event on my calendar I can have different daily/weekly, etc views on a calendar to see the "big picture" must run on mac os x leopard price does not matter, I will pay for this So, according to your experience, can you recommend me something like this? Thanks

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  • Why is the Windows 8 recycle bin using more space than it is allocated?

    - by oldmankit
    I ran WinDirStat to scan the contents of my hard drive. I was surprised to see that the $RECYCLE.BIN folder on my D: drive takes 26 GB of space. I emptied the recycle bin, refreshed the folder in WinDirStat, but it still takes 26 GB of space. I reduced the Maximum size of the recycle bin for this drive to 10000 MB for the main user of this computer, and disabled the recycle bin for the other user, and refreshed the folder in WinDirStat, but it still takes 26 GB of space. I ran (in an elevated window) rd /s D:\$Recycle.bin, and refreshed the folder in WinDirStat, and finally it became empty. Why was it taking up space even after I emptied it? Why was it taking more space (26 GB) than the maximum allowed amount (10 GB)? Update: After six months of using Windows (no re-install and no changes of settings related to the Recycle Bin) I used WinDirStat to check how big D:\$RECYCLE.BIN has become. It is now 29 GB. In Recycle Bin Properties, I select drive D, and it is still a custom maximum size (10000 MB).

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  • Green flickering pixels that move with black images

    - by user568458
    Strange question... Occasionally, on my LCD screen, pixels that should be black flicker rapidly and constantly between black and green, about 4 flickers a second. The crazy part is, unlike dead/stuck pixels, they are relative to content on the screen and move with it. For example, I might be looking at a web page with a picture that has lots of black. There might be a couple of green flashing pixels in that black that shouldn't be there. I scroll the page, and the green flickering pixels move with the image. It seems that everyphysical pixel is fine, but somehow something interprets part of the image in a way that causes flickering green... It's not just in a web browser. My first thought was to blame a trolling blogger cunningly uploading an animated gif that simulates a failing pixel... but it happens in a wide range of applications. It seems to occur randomly, other than that it seems to only occur in areas of pure black, and it's always pure 100% green. It happens rarely enough that it's not a big deal, but it's such a strange problem it bugs me. I can't find any info on anything like this. I'm not even sure if it's hardware or software. Any ideas? (windows 7 laptop connected to LCD by DVI to HDMI cable)

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  • Legal IT documents

    - by TylerShads
    I have been wondering this past week because my big boss told me to start keeping track of all the things I have fixed, how to fix them, etc. Which is reasonable and have been doing anyway. But then a related question came to mind. What kind of documentation should I have on hand as far as users go. More specifically I am talking in terms of EULA, ToC, etc (correct me please if I'm using the wrong terms) Or more specifically a policy, so to speak, for the users and such. Can't say I'm a legal expert, otherwise I'd be a lawyer. The environment the users are in is pretty laid back so I don't forsee a problem. But assume that there should ever arise a problem, what should I have written up/have on hand? EDIT: I really should have noted that we are a medical transport facility and have patient records so I know that something must be done there to comply with HIPAA policies I believe. I do like what anthonysomerset said about the "If I get by a bus" Scenario and want to apply it not only to the documentation I am currently writing but also for if say an employee were to steal info from the server or edge cases, theft, etc. As far as our staff, its relatively small as in a single HR person, no legal department aside from the 2 owners' lawyers and me being the only IT person on staff with a guy who is no more than a mac superuser.

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