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  • How to make quicksilver remember custom trigger

    - by corroded
    I am trying to make a custom trigger for my shell/apple script file to run so I can just launch my dev environment at the push of a button. So basically: I have a shell script(and some apple script included) in ~ named start_server.sh which does 3 things: start up solr server start up memcached start up script/server I have a saved quicksilver command(.qs) that opens up start_server.sh(so start_server.sh, then the action is "Run in Terminal") I created a custom trigger that calls this saved qs command. I did that then tested it and it works. I then tried to double check it so I quit quicksilver and when I checked the triggers it just said: "Open (null)" as the action. I set the trigger again and when i restarted QS the same thing happened again. I don't know why but my old custom trigger to open terminal has worked since forever so why doesn't this one work? Here's a screenie of the triggers after I restart QS: http://grab.by/4XWW If you have any other suggestion on how to make a "push button" start for my server then please do so :) Thanks! As an added note, I have already tried the steps on this thread but to no avail: http://groups.google.com/group/blacktree-quicksilver/browse_thread/thread/7b65ecf6625f8989

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  • Possible Solution for Setting up a Linux VPN Server to Encrypt WLAN Traffic of Macs and iPhones on

    - by GorillaPatch
    I would like to set up a VPN server on debian linux to encrypt wireless traffic coming from my Mac or iOS device. I would like to use a certificate-based solution. Setting up a PKI infrastructure and managing certificates is OK for me. 1. Which server to pick? By looking through the internet and here on stackoverflow I found the following possible solutions: strongSwan IPSec and racoon Which solution is feasible for a linode running debian squeeze? 2. How to configure the network? If I understood correctly a VPN has a virtual network interface as an endpoint on the server side. Naively I would think that I need a DHCP server running on the server to assign a dynamic private IP (like of the class C network 192.168.xxx.xxx) to the connecting clients. Next I think I would need to set up masquerading to NAT the incoming VPN traffic to the real interface directly connected to the internet. Is this the right way to go? Do you have any configuration examples? I often saw VPN configurations used to connect to your home network, but that is not what I am looking for. I have a server up in the internet and want to use it as a proxy to encrypt traffic in insecure network environments like public WLANs.

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  • tftpd starts randomly

    - by Mutant
    A few days ago my Little Snitch filter starts popping up tftpd. I'd never seen this before, so I immediately start freaking out thinking my Mac has been compromised. I can't find anything unusual on the system. The process usually dies before I can trace it (little snitch never allowed the connection just left the popup up). I finally caught it once, and found this: [10:32]: sudo lsof -nlP | fgrep tftp Password: tftpd 1924 18446744 cwd DIR 1,3 1326 2 / tftpd 1924 18446744 txt REG 1,3 29856 163979456 /usr/libexec/tftpd tftpd 1924 18446744 txt REG 1,3 600576 163686622 /usr/lib/dyld tftpd 1924 18446744 txt REG 1,3 303300608 189014898 /private/var/db/dyld/dyld_shared_cache_x86_64 tftpd 1924 18446744 0u IPv4 0x34a76100fcbb06e3 0t0 UDP *:55818 tftpd 1924 18446744 2u IPv4 0x34a76100f1113c53 0t0 UDP *:69 [10:32]: ps ax | fgrep 1924 1924 ?? S 0:00.00 /usr/libexec/tftpd -i /private/tftpboot 1949 s000 S+ 0:00.00 fgrep 1924 For the life of me I can't figure out what is starting this. Nothing in cron, launchdaemons, etc. Google searches haven't yielded much either. The connection IP is different each time. So my question is: Has anyone seen anything like this before?

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  • Onboard Ethernet suddenly stopped working to router

    - by AfterschoolHobbist
    Hey guys, yesterday I have a sudden problem of my Ethernet connection to my router. My computer is a Pendium 4 with Window XP SP3 running on it and it was working fine earlier in the day, but yesterday night was the start of the problem. My computer is unable to ping to the router and to any other website and unable to get internet connection. As beside it was connected to a hub, I directly connected it to the router directly and the same problem occurred, being unable to ping to the router (and connecting to it) and still no internet access. My directly connected to the modem and the problem still persisted. For each connection, I connected it to my computer and my laptop and my laptop was able to connect, while my desktop computer was unable. I wondered if it was a OS issue and ran a live Ubuntu CD to see if Ubuntu was able to connect to the internet, but the issue persisted and I was unable to get internet access. I then set my router's lease time to 1 hour and waited. After 1 hour, the lease for my computer was removed and I hoped this worked, but it didn't work, but something strange is acting up. My desktop computer is still unable to ping to the router or connect to the internet, but for some reason, my router and desktop computer is still able to contact each other by providing a lease of an local ip address. The router record of a lease to my desktop computer, and when I do ipconfig, my desktop also recognize that it has been provided a local ip address. I have concluded that this is a hardware issue and the only solution to fix this is to by a network card adapter, but I am wondering if anyone has any solutions that could explain why this happen, why my mac address is 01-23-45-67-89-ab, and is there any way to fix it without buying a new network card? Thanks in advance.

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  • Something like Dropbox for local use

    - by Casper
    I am looking for a solution to sync folder pairs between a NAS and multiple local macs. Each of the macs could edit files and the other macs should then get synced automatically. Basically my own local version of Dropbox without using "cloud-storage". I have looked into solutions using rsync. As I understand it rsync is not really capable of doing a bi-directional sync. I also do not want to necessarily invoke the sync process. I would prefer a daemon running in the background - waiting and checking for changes and then syncing them "live". The program should also be flexible enough to recognize that it sometimes (in the case with laptops) can not reach the NAS. It should then just wait for the connection to be back again, without bugging me ever few minutes. I have looked into synk, folderwatch, rsync and a few others, but I haven't really found a solution. Isn't there something like "offline folders" from microsoft for the mac? Thanks PS: just for clarification - I don't want to sync for backup purposes, instead I am wanting to sync so that all macs have a local copy of the most recent changes to files.

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  • Is there any way to get spotlight or media browser in OSX (Snow Leopard) to index and recognize meta

    - by jaydles
    It seems silly to go to all the trouble to assign "Face" data to thousands of photos, but not make it possible to use that data to locate them outside of that application. I know that that metadata is stored in the "library" database for Aperture/iphoto, rather than on the actual files (which is too bad). And I can even potentially see why it might create challenges for spotlight to use it, since spotlight if presumably a file index system, not a media organizer, but surely the media browser used across the other OSX apps is intended to use it? The media browser's whole purpose seems to be to let you easily locate and reference the items you organize in one of the ilife apps (iphoto or Aperture, in this case) from the others (say, imovie, or Mail). It's particularly vexing since the photo app on the iphone sorts by faces by default. Additionally, the mac-based media browser does access smart albums and folders, so you could establish a workaround by creating a smart album for each "face" or place, or tag, and access them that way, but it seems like there must be an easier way. Am I missing something?

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  • Sed: Deleting all content matching a pattern

    - by Svish
    I have some plist files on mac os x that I would like to shrink. They have a lot of <dict> with <key> and values. One of these keys is a thumbnail which has a <data> value with base64 encoded binary (I think). I would like to remove this key and value. I was thinking this could maybe be done by sed, but I don't really know how to use it and it seems like sed only works on a line-by-line basis? Either way I was hoping someone could help me out. In the file I would like to delete everything that matches the following pattern or something close to that: <key>Thumbnail<\/key>[^<]*<\/data> In the file it looks like this: // Other keys and values <key>Thumbnail</key> <data> TU0AKgAAOEi25Pqx3/ip2fak0vOdzPCVxu2RweuPv+mLu+mIt+aGtuaEtOSB ... dCBBcHBsZSBDb21wdXRlciwgSW5jLiwgMjAwNQAAAAA= </data> // Other keys and values Anyone know how I could do this? Also, if there are any better tools that I can use in the terminal to do this, I would like to know about that as well :)

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  • Routing connections through VPN based on hostname (not IP range)

    - by Michal M
    This bugs me immensly. I need to connect to client's network through VPN. But I definitely do not want to send all the traffic through client's network so this option is out of question. What I need basically is for the OS to know that all client's network subdomains (*.example.com) need to go through the VPN connection. I tried a couple of options: Changing order of services and setting the VPN on top, but this works the same as "Send all traffic over VPN connection". Using "VPN on Demand" option from network advanced options, but this feature is quite rubbish to be honest. Seems to work only in Safari (?!) and it doesn't route the connection, but it basically triggers the OS to connect to the selected VPN. The reason I need it to work based on hostnames rather than IP range is simple - my client has a lot of servers inside his network and it's impossible for me to remember all IPs. They are all within a range, but this doesn't help me remembering. Another option would be to put the VPN connection on the bottom of network services and untick "Send all traffic..." and then put all known hostnames in hosts file, but considering there could be hundreds of servers (therefore hostnames and ips too) it ridiculous job. And if new server appears on the network I'd need to edit the hosts file again. Sisyphean labours. However this works on Windows very simply. If a hostname is not available through default network interface, then it seems to try VPN connection and this works brilliantly. So, how can I achieve that on Mac, then? I know client's internal DNS addresses if that is of any help (like directing a certain domains through a different DNS)? PS. Using latest version 10.6.6. PS2. I am using VPN to access intranet, version control servers (svn://), samba shares and for SSH access to servers.

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  • Is there really such a thing as a char or short in modern programming?

    - by Dean P
    Howdy all, I've been learning to program for a Mac over the past few months (I have experience in other languages). Obviously that has meant learning the Objective C language and thus the plainer C it is predicated on. So I have stumbles on this quote, which refers to the C/C++ language in general, not just the Mac platform. With C and C++ prefer use of int over char and short. The main reason behind this is that C and C++ perform arithmetic operations and parameter passing at integer level, If you have an integer value that can fit in a byte, you should still consider using an int to hold the number. If you use a char, the compiler will first convert the values into integer, perform the operations and then convert back the result to char. So my question, is this the case in the Mac Desktop and IPhone OS environments? I understand when talking about theses environments we're actually talking about 3-4 different architectures (PPC, i386, Arm and the A4 Arm variant) so there may not be a single answer. Nevertheless does the general principle hold that in modern 32 bit / 64 bit systems using 1-2 byte variables that don't align with the machine's natural 4 byte words doesn't provide much of the efficiency we may expect. For instance, a plain old C-Array of 100,000 chars is smaller than the same 100,000 ints by a factor of four, but if during an enumeration, reading out each index involves a cast/boxing/unboxing of sorts, will we see overall lower 'performance' despite the saved memory overhead?

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  • assign characters to key combinations in XP or Visual Studio .Net

    - by cpj
    I'm running Mac OSX on a MacBookPro (UK keyboard). I run windows XP under parallels in a VM. I run Visual Studio .Net 2003 and 2008 in XP in the VM when i need to. I have English United Kingdom and English United states keyboards setup in XP. (they switch sometimes for no apparent reason) There is no hash "#" key on my mac's keyboard. However, in OSX I can get a hash with an alt+3 key combination. But In Windows XP... I can not make a "#" character. I can go to the character map in windows and copy a hash.. switch into OSX and copy a hash.. search in code and copy a hash.. but I can not make a hash in XP using my keyboard without typing U+0023: ... which you can imagine is annoying. coding anything with hash symbols is becoming a choir. Anyone got any advice or key mapping tricks I can use to get hash characters working in XP using my mac UK keyboard?

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  • Macports Apache not starting at Mac osx snow leopard boot

    - by greg
    Macports Apache2 not starting at Mac Osx snow leopard boot. I've done the launchctl load command, the symlinks point to my /opt/local//etc/LaunchDaemeons/org.macports.apache2/org.macports.apache2.plist, but it never starts. I can start it manually, works fine after that. Just wont load on startup. My server is named in my /opt/localapache2/conf/httd.conf, I had read that sometimes makes a difference. I've done the launchctl unload and load trick, al with no results. I'm out of ideas.

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  • Macports Apache not starting at Mac osx snow leopard boot

    - by greg
    Macports Apache2 not starting at Mac Osx snow leopard boot. I've done the launchctl load command, the symlinks point to my /opt/local//etc/LaunchDaemeons/org.macports.apache2/org.macports.apache2.plist, but it never starts. I can start it manually, works fine after that. Just wont load on startup. My server is named in my /opt/localapache2/conf/httd.conf, I had read that sometimes makes a difference. I've done the launchctl unload and load trick, al with no results. I'm out of ideas.

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  • Where do all the old programmers go?

    - by Tony Lambert
    I know some people move over to management and some die... but where do the rest go and why? One reason people change to management is that in some companies the "Programmer" career path is very short - you can get to be a senior programmer within a few years. Leaving no way to get more money but to become a manager. In other companies project managers and programmers are parallel career paths so your project manager can be your junior. Tony

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  • Firewire hard drive with Leopard install image won't boot from PPC Mac Mini

    - by GregH
    I have a Mac Mini (G4 - 1.25 GHz PowerPC) running osx 10.3.9. I want to upgrade it to 10.5 (Leopard). The problem is that I only have a CD and no DVD. After working through all of these issues, I got myself a firewire hard drive and both a 10.4 and 10.5 image that I could image on to the hard drive. I was able to successfully boot off the firewire drive with the 10.4 image. However, I am not able to boot off the firewire drive with the 10.5 image. When trying to boot under the 10.5 image I specify the firewire drive as the startup drive. However, it just boots to the internal (10.3) drive. Any idea why it won't boot to the 10.5 image?

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  • Mac OS can't connect to SMB shares after sleep

    - by Andreas
    I used to access my local Windows 2008 file server's SMB shares on my recent (3 weeks old) MacBook Pro without problems. However, for a few days now, it fails to (re-)connect to the server after it woke up from sleep mode. Finder just shows "connecting..." and hangs indefinitely. The same thing happens when I try it from the command line (mount -t smbfs). This happens via both WiFi and cable, I also tried turning networking off and back on. The only thing that helps is a reboot. Any hints?

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  • Wix - Upgrade always runs older installer msi and fails in trying to read old msi

    - by rkhj
    I'm having a problem though with the Windows caching of the installer. I'm trying to do an upgrade and each time the Windows installer is launching the installer of the older version. And when I do the upgrade it is complaining about problems with reading the older version's msi file (because its not in the same directory anymore). I did change the UpgradeCode and the ProductCode but kept the PackageCode the same. I also have different ProductVersion codes (2.2.3 vs 2.3.0). Here's a sample of my code: <Upgrade Id="$(var.UpgradeCode)"> <UpgradeVersion Property="OLDAPPFOUND" IncludeMinimum="yes" Minimum="$(var.RTMProductVersion)" IncludeMaximum="no" Maximum="$(var.ProductVersion)"/> <UpgradeVersion Property="NEWAPPFOUND" IncludeMinimum="no" Minimum="$(var.ProductVersion)" OnlyDetect="yes"/> </Upgrade> This is the Install Sequence: <InstallExecuteSequence> <Custom Action='SetUpgradeParams' After='InstallFiles'>Installed AND NEWAPPFOUND</Custom> <Custom Action='Upgrade' After='SetUpgradeParams'>Installed AND NEWAPPFOUND</Custom> </InstallExecuteSequence> The error I am getting is: A network error occurred while attempting to read from the file: Thanks,

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  • Linux equivalent to Mac OS X's fs_usage

    - by Khai
    Is there a Linux equivalent to the Mac OS X command fs_usage? According to the man page it does the following: "report system calls and page faults related to filesystem activity in real-time". I suppose one option would be to use strace and filter the data, however the fs_usage command allows all the processes running on the system to be "traced" at the same time. Here's an example output: 03:44:25 stat64 erences/ByHost/org.mozilla.firefox.69AC0B48-F675-5045-B873-A28B119C33E7.plist 0.000029 firefox 03:44:25 stat64 /Users/**********/Library/Preferences 0.000011 firefox 03:44:25 statfs64 /Users/**********/Library/Preferences 0.000004 firefox 03:44:25 open /Users/**********/Library/Preferences/org.mozilla.firefox.plist.lockfile 0.000090 firefox 03:44:25 stat64 /Users/**********/Library/Preferences/org.mozilla.firefox.plist 0.000004 firefox 03:44:25 stat64 /Users/**********/Library/Preferences 0.000002 firefox 03:44:25 open /Users/**********/Library/Preferences/org.mozilla.firefox.plist.vjLkANe 0.000100 firefox Any ideas?

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  • Restoring Time Machine from two Macs onto one (new) mac

    - by Dan
    My parents used to have two Macs...a "iLamp-style" iMac for my Dad, and an iBook G4 for my Mom. A while back, I had setup the iMac to have an external Firewire Hard Drive for a Time Machine Volume, and backed up both the iMac and iBook to that drive. Recently, the iBook died and the iMac was really slow to work with. So my parents decided to replace the iBook with an iPad, and also purchased a Mac Mini. I need to help my parents get their data from their two computers (backed up by Time Machine) onto the same machine. Pretty much everything is identical between the two systems (same apps, etc), however, they both have individual email accounts and photos that they want to retain. Is it possible to do two Time Machine restores onto one computer?

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  • Firefox: How do I disable AddOns on my Mac

    - by lexu
    This morning firefox told me it needed to upgrade an addon (noflash) and I told it to go ahead. Now Firefox won't start. How can I prevent Firefox from loading the addons? On a windows site I found the hint to start Firefox in safe mode using Firefox -safe-mode from the command line .. how do I do that on the Mac ... /Applications/Firefox.app is a directory after all. Where are the Firefox config files?

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  • iptables syn flood countermeasure

    - by Penegal
    I'm trying to adjust my iptables firewall to increase the security of my server, and I found something a bit problematic here : I have to set INPUT policy to ACCEPT and, in addition, to have a rule saying iptables -I INPUT -i eth0 -j ACCEPT. Here comes my script (launched manually for tests) : #!/bin/sh IPT=/sbin/iptables echo "Clearing firewall rules" $IPT -F $IPT -Z $IPT -t nat -F $IPT -t nat -Z $IPT -t mangle -F $IPT -t mangle -Z $IPT -X echo "Defining logging policy for dropped packets" $IPT -N LOGDROP $IPT -A LOGDROP -j LOG -m limit --limit 5/min --log-level debug --log-prefix "iptables rejected: " $IPT -A LOGDROP -j DROP echo "Setting firewall policy" $IPT -P INPUT DROP # Deny all incoming connections $IPT -P OUTPUT ACCEPT # Allow all outgoing connections $IPT -P FORWARD DROP # Deny all forwaring echo "Allowing connections from/to lo and incoming connections from eth0" $IPT -I INPUT -i lo -j ACCEPT $IPT -I OUTPUT -o lo -j ACCEPT #$IPT -I INPUT -i eth0 -j ACCEPT echo "Setting SYN flood countermeasures" $IPT -A INPUT -p tcp -i eth0 --syn -m limit --limit 100/second --limit-burst 200 -j LOGDROP echo "Allowing outgoing traffic corresponding to already initiated connections" $IPT -A OUTPUT -p ALL -m state --state ESTABLISHED,RELATED -j ACCEPT echo "Allowing incoming SSH" $IPT -A INPUT -p tcp --dport 22 -m state --state NEW -m recent --set --name SSH -j ACCEPT echo "Setting SSH bruteforce attacks countermeasures (deny more than 10 connections every 10 minutes)" $IPT -A INPUT -p tcp --dport 22 -m recent --update --seconds 600 --hitcount 10 --rttl --name SSH -j LOGDROP echo "Allowing incoming traffic for HTTP, SMTP, NTP, PgSQL and SolR" $IPT -A INPUT -p tcp --dport 25 -i eth0 -j ACCEPT $IPT -A INPUT -p tcp --dport 80 -i eth0 -j ACCEPT $IPT -A INPUT -p udp --dport 123 -i eth0 -j ACCEPT $IPT -A INPUT -p tcp --dport 5433 -i eth0.2654 -s 172.16.0.2 -j ACCEPT $IPT -A INPUT -p udp --dport 5433 -i eth0.2654 -s 172.16.0.2 -j ACCEPT $IPT -A INPUT -p tcp --dport 8983 -i eth0.2654 -s 172.16.0.2 -j ACCEPT $IPT -A INPUT -p udp --dport 8983 -i eth0.2654 -s 172.16.0.2 -j ACCEPT echo "Allowing outgoing traffic for ICMP, SSH, whois, SMTP, DNS, HTTP, PgSQL and SolR" $IPT -A OUTPUT -p tcp --dport 22 -j ACCEPT $IPT -A OUTPUT -p tcp --dport 25 -o eth0 -j ACCEPT $IPT -A OUTPUT -p tcp --dport 43 -o eth0 -j ACCEPT $IPT -A OUTPUT -p tcp --dport 53 -o eth0 -j ACCEPT $IPT -A OUTPUT -p udp --dport 53 -o eth0 -j ACCEPT $IPT -A OUTPUT -p tcp --dport 80 -o eth0 -j ACCEPT $IPT -A OUTPUT -p udp --dport 80 -o eth0 -j ACCEPT #$IPT -A OUTPUT -p tcp --dport 5433 -o eth0 -d 176.31.236.101 -j ACCEPT #$IPT -A OUTPUT -p udp --dport 5433 -o eth0 -d 176.31.236.101 -j ACCEPT #$IPT -A OUTPUT -p tcp --dport 8983 -o eth0 -d 176.31.236.101 -j ACCEPT #$IPT -A OUTPUT -p udp --dport 8983 -o eth0 -d 176.31.236.101 -j ACCEPT $IPT -A OUTPUT -p tcp --sport 5433 -o eth0.2654 -j ACCEPT $IPT -A OUTPUT -p udp --sport 5433 -o eth0.2654 -j ACCEPT $IPT -A OUTPUT -p tcp --sport 8983 -o eth0.2654 -j ACCEPT $IPT -A OUTPUT -p udp --sport 8983 -o eth0.2654 -j ACCEPT $IPT -A OUTPUT -p icmp -j ACCEPT echo "Allowing outgoing FTP backup" $IPT -A OUTPUT -p tcp --dport 20:21 -o eth0 -d 91.121.190.78 -j ACCEPT echo "Dropping and logging everything else" $IPT -A INPUT -s 0/0 -j LOGDROP $IPT -A OUTPUT -j LOGDROP $IPT -A FORWARD -j LOGDROP echo "Firewall loaded." echo "Maintaining new rules for 3 minutes for tests" sleep 180 $IPT -nvL echo "Clearing firewall rules" $IPT -F $IPT -Z $IPT -t nat -F $IPT -t nat -Z $IPT -t mangle -F $IPT -t mangle -Z $IPT -X $IPT -P INPUT ACCEPT $IPT -P OUTPUT ACCEPT $IPT -P FORWARD ACCEPT When I launch this script (I only have a SSH access), the shell displays every message up to Maintaining new rules for 3 minutes for tests, the server is unresponsive during the 3 minutes delay and then resume normal operations. The only solution I found until now was to set $IPT -P INPUT ACCEPT and $IPT -I INPUT -i eth0 -j ACCEPT, but this configuration does not protect me of any attack, which is a great shame for a firewall. I suspect that the error comes from my script and not from iptables, but I don't understand what's wrong with my script. Could some do-gooder explain me my error, please? EDIT: here comes the result of iptables -nvL with the "accept all input" ($IPT -P INPUT ACCEPT and $IPT -I INPUT -i eth0 -j ACCEPT) solution : Chain INPUT (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination 1 52 ACCEPT all -- eth0 * 0.0.0.0/0 0.0.0.0/0 0 0 ACCEPT all -- lo * 0.0.0.0/0 0.0.0.0/0 0 0 LOGDROP tcp -- eth0 * 0.0.0.0/0 0.0.0.0/0 tcp flags:0x17/0x02 limit: avg 100/sec burst 200 0 0 ACCEPT tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:22 state NEW recent: SET name: SSH side: source 0 0 LOGDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:22 recent: UPDATE seconds: 600 hit_count: 10 TTL-Match name: SSH side: source 0 0 ACCEPT tcp -- eth0 * 0.0.0.0/0 0.0.0.0/0 tcp dpt:25 0 0 ACCEPT tcp -- eth0 * 0.0.0.0/0 0.0.0.0/0 tcp dpt:80 0 0 ACCEPT udp -- eth0 * 0.0.0.0/0 0.0.0.0/0 udp dpt:123 0 0 ACCEPT tcp -- eth0.2654 * 172.16.0.2 0.0.0.0/0 tcp dpt:5433 0 0 ACCEPT udp -- eth0.2654 * 172.16.0.2 0.0.0.0/0 udp dpt:5433 0 0 ACCEPT tcp -- eth0.2654 * 172.16.0.2 0.0.0.0/0 tcp dpt:8983 0 0 ACCEPT udp -- eth0.2654 * 172.16.0.2 0.0.0.0/0 udp dpt:8983 0 0 LOGDROP all -- * * 0.0.0.0/0 0.0.0.0/0 Chain FORWARD (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination 0 0 LOGDROP all -- * * 0.0.0.0/0 0.0.0.0/0 Chain OUTPUT (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination 0 0 ACCEPT all -- * lo 0.0.0.0/0 0.0.0.0/0 2 728 ACCEPT all -- * * 0.0.0.0/0 0.0.0.0/0 state RELATED,ESTABLISHED 0 0 ACCEPT tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:22 0 0 ACCEPT tcp -- * eth0 0.0.0.0/0 0.0.0.0/0 tcp dpt:25 0 0 ACCEPT tcp -- * eth0 0.0.0.0/0 0.0.0.0/0 tcp dpt:43 0 0 ACCEPT tcp -- * eth0 0.0.0.0/0 0.0.0.0/0 tcp dpt:53 0 0 ACCEPT udp -- * eth0 0.0.0.0/0 0.0.0.0/0 udp dpt:53 0 0 ACCEPT tcp -- * eth0 0.0.0.0/0 0.0.0.0/0 tcp dpt:80 0 0 ACCEPT udp -- * eth0 0.0.0.0/0 0.0.0.0/0 udp dpt:80 0 0 ACCEPT tcp -- * eth0.2654 0.0.0.0/0 0.0.0.0/0 tcp spt:5433 0 0 ACCEPT udp -- * eth0.2654 0.0.0.0/0 0.0.0.0/0 udp spt:5433 0 0 ACCEPT tcp -- * eth0.2654 0.0.0.0/0 0.0.0.0/0 tcp spt:8983 0 0 ACCEPT udp -- * eth0.2654 0.0.0.0/0 0.0.0.0/0 udp spt:8983 0 0 ACCEPT icmp -- * * 0.0.0.0/0 0.0.0.0/0 0 0 ACCEPT tcp -- * eth0 0.0.0.0/0 91.121.190.78 tcp dpts:20:21 0 0 LOGDROP all -- * * 0.0.0.0/0 0.0.0.0/0 Chain LOGDROP (5 references) pkts bytes target prot opt in out source destination 0 0 LOG all -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 5/min burst 5 LOG flags 0 level 7 prefix `iptables rejected: ' 0 0 DROP all -- * * 0.0.0.0/0 0.0.0.0/0 EDIT #2 : I modified my script (policy ACCEPT, defining authorized incoming packets then logging and dropping everything else) to write iptables -nvL results to a file and to allow only 10 ICMP requests per second, logging and dropping everything else. The result proved unexpected : while the server was unavailable to SSH connections, even already established, I ping-flooded it from another server, and the ping rate was restricted to 10 requests per second. During this test, I also tried to open new SSH connections, which remained unanswered until the script flushed rules. Here comes the iptables stats written after these tests : Chain INPUT (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination 600 35520 ACCEPT all -- lo * 0.0.0.0/0 0.0.0.0/0 6 360 LOGDROP tcp -- eth0 * 0.0.0.0/0 0.0.0.0/0 tcp flags:0x17/0x02 limit: avg 100/sec burst 200 0 0 LOGDROP tcp -- eth0 * 0.0.0.0/0 0.0.0.0/0 tcp dpt:80 STRING match "w00tw00t.at.ISC.SANS." ALGO name bm TO 65535 0 0 LOGDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:80 STRING match "Host: anoticiapb.com.br" ALGO name bm TO 65535 0 0 LOGDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:80 STRING match "Host: www.anoticiapb.com.br" ALGO name bm TO 65535 105 8820 ACCEPT icmp -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 10/sec burst 5 830 69720 LOGDROP icmp -- * * 0.0.0.0/0 0.0.0.0/0 0 0 ACCEPT tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:22 state NEW recent: SET name: SSH side: source 0 0 LOGDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:22 recent: UPDATE seconds: 600 hit_count: 10 TTL-Match name: SSH side: source 0 0 ACCEPT tcp -- eth0 * 0.0.0.0/0 0.0.0.0/0 tcp dpt:25 0 0 ACCEPT tcp -- eth0 * 0.0.0.0/0 0.0.0.0/0 tcp dpt:80 0 0 ACCEPT udp -- eth0 * 0.0.0.0/0 0.0.0.0/0 udp dpt:80 0 0 ACCEPT udp -- eth0 * 0.0.0.0/0 0.0.0.0/0 udp dpt:123 0 0 ACCEPT tcp -- eth0 * 0.0.0.0/0 0.0.0.0/0 tcp dpt:443 0 0 ACCEPT tcp -- eth0.2654 * 172.16.0.1 0.0.0.0/0 tcp spt:5433 0 0 ACCEPT udp -- eth0.2654 * 172.16.0.1 0.0.0.0/0 udp spt:5433 0 0 ACCEPT tcp -- eth0.2654 * 172.16.0.1 0.0.0.0/0 tcp spt:8983 0 0 ACCEPT udp -- eth0.2654 * 172.16.0.1 0.0.0.0/0 udp spt:8983 16 1684 LOGDROP all -- * * 0.0.0.0/0 0.0.0.0/0 Chain FORWARD (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination 0 0 LOGDROP all -- * * 0.0.0.0/0 0.0.0.0/0 Chain OUTPUT (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination 600 35520 ACCEPT all -- * lo 0.0.0.0/0 0.0.0.0/0 0 0 LOGDROP tcp -- * eth0 0.0.0.0/0 0.0.0.0/0 tcp dpt:80 owner UID match 33 0 0 LOGDROP udp -- * eth0 0.0.0.0/0 0.0.0.0/0 udp dpt:80 owner UID match 33 116 11136 ACCEPT all -- * * 0.0.0.0/0 0.0.0.0/0 state RELATED,ESTABLISHED 0 0 ACCEPT tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:22 0 0 ACCEPT tcp -- * eth0 0.0.0.0/0 0.0.0.0/0 tcp dpt:25 0 0 ACCEPT tcp -- * eth0 0.0.0.0/0 0.0.0.0/0 tcp dpt:53 0 0 ACCEPT udp -- * eth0 0.0.0.0/0 0.0.0.0/0 udp dpt:53 0 0 ACCEPT tcp -- * eth0 0.0.0.0/0 0.0.0.0/0 tcp dpt:80 0 0 ACCEPT udp -- * eth0 0.0.0.0/0 0.0.0.0/0 udp dpt:80 0 0 ACCEPT tcp -- * eth0.2654 0.0.0.0/0 0.0.0.0/0 tcp dpt:5433 0 0 ACCEPT udp -- * eth0.2654 0.0.0.0/0 0.0.0.0/0 udp dpt:5433 0 0 ACCEPT tcp -- * eth0.2654 0.0.0.0/0 0.0.0.0/0 tcp dpt:8983 0 0 ACCEPT udp -- * eth0.2654 0.0.0.0/0 0.0.0.0/0 udp dpt:8983 0 0 ACCEPT icmp -- * * 0.0.0.0/0 0.0.0.0/0 0 0 ACCEPT tcp -- * eth0 0.0.0.0/0 0.0.0.0/0 tcp dpt:43 0 0 ACCEPT tcp -- * eth0 0.0.0.0/0 91.121.190.18 tcp dpts:20:21 7 1249 LOGDROP all -- * * 0.0.0.0/0 0.0.0.0/0 Chain LOGDROP (11 references) pkts bytes target prot opt in out source destination 35 3156 LOG all -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 1/sec burst 5 LOG flags 0 level 7 prefix `iptables rejected: ' 859 73013 DROP all -- * * 0.0.0.0/0 0.0.0.0/0 Here comes the log content added during this test : Mar 28 09:52:51 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=52 TOS=0x00 PREC=0x00 TTL=51 ID=55666 DF PROTO=TCP SPT=57504 DPT=22 WINDOW=501 RES=0x00 ACK URGP=0 Mar 28 09:52:51 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=52 TOS=0x00 PREC=0x00 TTL=51 ID=55667 DF PROTO=TCP SPT=57504 DPT=22 WINDOW=501 RES=0x00 ACK URGP=0 Mar 28 09:52:51 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=64 TOS=0x00 PREC=0x00 TTL=51 ID=55668 DF PROTO=TCP SPT=57504 DPT=22 WINDOW=501 RES=0x00 ACK URGP=0 Mar 28 09:52:51 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=64 TOS=0x00 PREC=0x00 TTL=51 ID=55669 DF PROTO=TCP SPT=57504 DPT=22 WINDOW=501 RES=0x00 ACK URGP=0 Mar 28 09:52:52 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=64 TOS=0x00 PREC=0x00 TTL=51 ID=55670 DF PROTO=TCP SPT=57504 DPT=22 WINDOW=501 RES=0x00 ACK URGP=0 Mar 28 09:52:54 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=64 TOS=0x00 PREC=0x00 TTL=51 ID=55671 DF PROTO=TCP SPT=57504 DPT=22 WINDOW=501 RES=0x00 ACK URGP=0 Mar 28 09:52:58 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=64 TOS=0x00 PREC=0x00 TTL=51 ID=55672 DF PROTO=TCP SPT=57504 DPT=22 WINDOW=501 RES=0x00 ACK URGP=0 Mar 28 09:52:59 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=176.31.236.101 DST=176.31.238.3 LEN=84 TOS=0x00 PREC=0x00 TTL=63 ID=0 DF PROTO=ICMP TYPE=8 CODE=0 ID=7430 SEQ=6 Mar 28 09:52:59 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=176.31.236.101 DST=176.31.238.3 LEN=84 TOS=0x00 PREC=0x00 TTL=63 ID=0 DF PROTO=ICMP TYPE=8 CODE=0 ID=7430 SEQ=7 Mar 28 09:52:59 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=176.31.236.101 DST=176.31.238.3 LEN=84 TOS=0x00 PREC=0x00 TTL=63 ID=0 DF PROTO=ICMP TYPE=8 CODE=0 ID=7430 SEQ=8 Mar 28 09:52:59 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=176.31.236.101 DST=176.31.238.3 LEN=84 TOS=0x00 PREC=0x00 TTL=63 ID=0 DF PROTO=ICMP TYPE=8 CODE=0 ID=7430 SEQ=9 Mar 28 09:52:59 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=176.31.236.101 DST=176.31.238.3 LEN=84 TOS=0x00 PREC=0x00 TTL=63 ID=0 DF PROTO=ICMP TYPE=8 CODE=0 ID=7430 SEQ=59 Mar 28 09:53:00 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=176.31.236.101 DST=176.31.238.3 LEN=84 TOS=0x00 PREC=0x00 TTL=63 ID=0 DF PROTO=ICMP TYPE=8 CODE=0 ID=7430 SEQ=152 Mar 28 09:53:01 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=176.31.236.101 DST=176.31.238.3 LEN=84 TOS=0x00 PREC=0x00 TTL=63 ID=0 DF PROTO=ICMP TYPE=8 CODE=0 ID=7430 SEQ=246 Mar 28 09:53:02 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=176.31.236.101 DST=176.31.238.3 LEN=84 TOS=0x00 PREC=0x00 TTL=63 ID=0 DF PROTO=ICMP TYPE=8 CODE=0 ID=7430 SEQ=339 Mar 28 09:53:03 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=176.31.236.101 DST=176.31.238.3 LEN=84 TOS=0x00 PREC=0x00 TTL=63 ID=0 DF PROTO=ICMP TYPE=8 CODE=0 ID=7430 SEQ=432 Mar 28 09:53:04 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=176.31.236.101 DST=176.31.238.3 LEN=84 TOS=0x00 PREC=0x00 TTL=63 ID=0 DF PROTO=ICMP TYPE=8 CODE=0 ID=7430 SEQ=524 Mar 28 09:53:05 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=176.31.236.101 DST=176.31.238.3 LEN=84 TOS=0x00 PREC=0x00 TTL=63 ID=0 DF PROTO=ICMP TYPE=8 CODE=0 ID=7430 SEQ=617 Mar 28 09:53:06 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=176.31.236.101 DST=176.31.238.3 LEN=84 TOS=0x00 PREC=0x00 TTL=63 ID=0 DF PROTO=ICMP TYPE=8 CODE=0 ID=7430 SEQ=711 Mar 28 09:53:07 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=176.31.236.101 DST=176.31.238.3 LEN=84 TOS=0x00 PREC=0x00 TTL=63 ID=0 DF PROTO=ICMP TYPE=8 CODE=0 ID=7430 SEQ=804 Mar 28 09:53:08 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=176.31.236.101 DST=176.31.238.3 LEN=84 TOS=0x00 PREC=0x00 TTL=63 ID=0 DF PROTO=ICMP TYPE=8 CODE=0 ID=7430 SEQ=897 Mar 28 09:53:16 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:c0:62:6b:e3:5c:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=60 TOS=0x00 PREC=0x00 TTL=51 ID=61402 DF PROTO=TCP SPT=57637 DPT=22 WINDOW=5840 RES=0x00 SYN URGP=0 Mar 28 09:53:19 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:c0:62:6b:e3:5c:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=60 TOS=0x00 PREC=0x00 TTL=51 ID=61403 DF PROTO=TCP SPT=57637 DPT=22 WINDOW=5840 RES=0x00 SYN URGP=0 Mar 28 09:53:21 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=64 TOS=0x00 PREC=0x00 TTL=51 ID=55674 DF PROTO=TCP SPT=57504 DPT=22 WINDOW=501 RES=0x00 ACK URGP=0 Mar 28 09:53:25 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:c0:62:6b:e3:5c:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=60 TOS=0x00 PREC=0x00 TTL=51 ID=61404 DF PROTO=TCP SPT=57637 DPT=22 WINDOW=5840 RES=0x00 SYN URGP=0 Mar 28 09:53:37 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=116 TOS=0x00 PREC=0x00 TTL=51 ID=55675 DF PROTO=TCP SPT=57504 DPT=22 WINDOW=501 RES=0x00 ACK PSH URGP=0 Mar 28 09:53:37 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=116 TOS=0x00 PREC=0x00 TTL=51 ID=55676 DF PROTO=TCP SPT=57504 DPT=22 WINDOW=501 RES=0x00 ACK PSH URGP=0 Mar 28 09:53:37 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=180 TOS=0x00 PREC=0x00 TTL=51 ID=55677 DF PROTO=TCP SPT=57504 DPT=22 WINDOW=501 RES=0x00 ACK PSH URGP=0 Mar 28 09:53:38 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=180 TOS=0x00 PREC=0x00 TTL=51 ID=55678 DF PROTO=TCP SPT=57504 DPT=22 WINDOW=501 RES=0x00 ACK PSH URGP=0 Mar 28 09:53:39 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=180 TOS=0x00 PREC=0x00 TTL=51 ID=55679 DF PROTO=TCP SPT=57504 DPT=22 WINDOW=501 RES=0x00 ACK PSH URGP=0 Mar 28 09:53:39 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:c0:62:6b:e3:5c:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=60 TOS=0x00 PREC=0x00 TTL=51 ID=5055 DF PROTO=TCP SPT=57638 DPT=22 WINDOW=5840 RES=0x00 SYN URGP=0 Mar 28 09:53:41 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=180 TOS=0x00 PREC=0x00 TTL=51 ID=55680 DF PROTO=TCP SPT=57504 DPT=22 WINDOW=501 RES=0x00 ACK PSH URGP=0 Mar 28 09:53:42 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:c0:62:6b:e3:5c:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=60 TOS=0x00 PREC=0x00 TTL=51 ID=5056 DF PROTO=TCP SPT=57638 DPT=22 WINDOW=5840 RES=0x00 SYN URGP=0 Mar 28 09:53:45 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:10:8c:cf:28:39:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=180 TOS=0x00 PREC=0x00 TTL=51 ID=55681 DF PROTO=TCP SPT=57504 DPT=22 WINDOW=501 RES=0x00 ACK PSH URGP=0 Mar 28 09:53:48 localhost kernel: iptables rejected: IN=eth0 OUT= MAC=00:25:90:54:d7:88:c0:62:6b:e3:5c:80:08:00 SRC=194.51.74.245 DST=176.31.238.3 LEN=60 TOS=0x00 PREC=0x00 TTL=51 ID=5057 DF PROTO=TCP SPT=57638 DPT=22 WINDOW=5840 RES=0x00 SYN URGP=0 If I correctly interpreted these results, they say that ICMP rules were correctly interpreted by iptables, but SSH rules were not. This does not make any sense... Does somebody understand where my error comes from? EDIT #3 : After some more tests, I found out that commenting the SYN flood countermeasure removes the problem. I continue researches in this way but, meanwhile, if somebody sees my anti SYN flood rule error...

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  • Throwing a new exception while throwing an old exception

    - by FredOverflow
    If a destructor throws in C++ during stack unwinding caused by an exception, the program terminates. (That's why destructors should never throw in C++.) If a finally block is entered in Java because of an exception in the corresponding try block and that finally block throws another exception, the first exception is silently swallowed. This question crossed my mind: Could a programming language handle multiple exceptions being thrown at the same time? Would that be useful? Have you ever missed that ability? Is there a language that already supports this? Is there any experience with such an approach? Any thoughts?

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  • What are modern and old compilers written in?

    - by ulum
    As a compiler, other than an interpreter, only needs to translate the input and not run it the performance of itself should be not that problematic as with an interpreter. Therefore, you wouldn't write an interpreter in, let's say Ruby or PHP because it would be far too slow. However, what about compilers? If you would write a compiler in a scripting language maybe even featuring rapid development you could possibly cut the source code and initial development time by halv, at least I think so. To be sure: With scripting language I mean interpreted languages having typical features that make programming faster, easier and more enjoyable for the programmer, usually at least. Examples: PHP, Ruby, Python, maybe JavaScript though that may be an odd choice for a compiler What are compilers normally written in? As I suppose you will respond with something low-level like C, C++ or even Assembler, why? Are there compilers written in scripting languages? What are the (dis)advantages of using low or high level programming languages for compiler writing?

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