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cat datemp.log
04/01/0902:11:42
Sys Temp: +11.0?C
CPU Temp: +35.5?C
AUX Temp: +3.0?C
Searches /var/log/secure for smtp connections then lists these by number of connections made and hosts.
If (when) you forget to "svn rm" files from your repository, use this to let your repository know you want those files gone. Of course this works with adding and reverting too.
Here is a command line to run on your server if you think your server is under attack. It prints our a list of open connections to your server and sorts them by amount.
BSD Version:
netstat -na |awk '{print $5}' |cut -d "." -f1,2,3,4 |sort |uniq -c |sort -nr
Allows you to save progress without committing.
To revert to an undo point, svn revert then apply the undo point with patch.
svn revert -R . && patch -p0 < .undo/2009-03-27_08:08:11rev57
Similar: http://www.commandlinefu.com/commands/view/373/archive-all-files-containing-local-changes-svn
This truncates any lines longer than 80 characters. Also useful for looking at different parts of the line, e.g. cut -b 50-100 shows columns 50 through 100.
This command will grep the entire directory looking for any files containing the list of files. This is useful for cleaning out your project of old static files that are no longer in use. Also ignores .svn directories for accurate counts. Replace 'static/images/' with the directory containing the files you want to search for.
This example summarize size of all pdf files in /tmp directory and its subdirectories (in bytes).
Replace "/tmp" with directory path of your choice and "\*pdf" or even "-iname \*pdf" with your own pattern to match specific type of files. You can replace also parameter for du to count kilo or megabytes, but because of du rounding the sum will not be correct (especially with lot of small files and megabytes counting).
In some cases you could probably use sth like this:
du -cb `find /tmp -type f -iname \*pdf`|tail -n 1
But be aware that this second command CANNOT count files with spaces in their names and it will cheat you, if there are some files matching the pattern that you don't have rights to read. The first oneliner is resistant to such problems (it will not count sizes of files which you cant read but will give you correct sum of rest of them).
queries local memcached for stats, calculates hit/get ratio and prints it out.
If you have some textfile with an unknown encoding you can use this list to find out
I know there are a lot of random password generators out there, but I wanted something that put out something besides hex. Set count equal to the number of bytes you want.
only works for freeBSD where ports are installed in /usr/ports
credit to http://wiki.freebsd.org/PortsTasks
This command does a tally of concurrent active connections from single IPs and prints out those IPs that have the most active concurrent connections. VERY useful in determining the source of a DoS or DDoS attack.
This will tell you who has the most Apache connections by IP (replace IPHERE with the actual IP you wish to check). Or if you wish, remove | grep -c IPHERE for the full list.
List top 20 IP from which TCP connection is in SYN_RECV state.
Useful on web servers to detect a syn flood attack.
Replace SYN_ with ESTA to find established connections