Commands by evenme (3)

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Change mysql prompt to be more verbose
You can put this into your shell sourced file like .bashrc or .zshrc to have a different mysql prompt. See http://dev.mysql.com/doc/refman/5.1/de/mysql-commands.html for more informations. Beware that currently with mysql 5.5 the seconds are buggy and won't be displayed if you put this into a .cnf file. With the enironment variable this will work.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

grep tab chars
mixing tabs and spaces for indentation in python would confuse the python interpreter, to avoid that, check if the file has any tab based indentation. "^V" => denotes press control + v and press tab within quotes. $ cat improper_indent.py class Tux(object): print "Hello world.." $ grep " " improper_indent.py print "Hello world.."

Sniffing network to generate a pcap file in CLI mode on a remote host and open it via local Wireshark ( GUI ).
Then hit ^C to stop, get the file by scp, and you can now use wireshark like this : $ wireshark /tmp/sniff.pcap If you have tshark on remote host, you could use that : $ wireshark -k -i

get a random 0/1, use it for on/off, yes/no
use it to add a random boolean switch to your script

Search for a process by name
ps and grep is a dangerous combination -- grep tries to match everything on each line (thus the all too common: grep -v grep hack). ps -C doesn't use grep, it uses the process table for an exact match. Thus, you'll get an accurate list with: ps -fC sh rather finding every process with sh somewhere on the line.

Create a 5 MB blank file via a seek hole
Similar to the original, but is much faster since it only needs to write the last byte as zero. A diff on testfile and testfile.seek will return that they are the same.

Chage default shell for all users [FreeBSD]
This command will set bash as the default shell for all users in a FreeBSD system.

Get a list of IP Addresses that have failed to login via SSH
This command shows a sorted list of the IP addresses from which there have been authentication errors via SSH (possible script kiddies trying to gain access to your server), it eliminates duplicates so it's easier to read, but you can remove the "uniq" command at the end, or even do a "uniq -c" to have a count of how many times each IP address shows in the log (the path to the log may vary from system to system)

Duplicate installed packages from one machine to the other (RPM-based systems)


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