Pario TechnoBlob » grep

My 10 most used linux commands

Hans-Henry Jakobsen — Mon, 25 Feb 2008 07:49:40 +0000

This is a oneliner bash command to determine my 10 most used linux commands according to my history file

history | awk '{CMD[$2]++;count++;}END { for (a in CMD)print CMD[a] " " CMD[a]/count*100 "% " a;}' | grep -v "./" | column -c3 -s " " -t | sort -nr | nl |  head -n10

The result

     1  188  37.6%  vi
     2  38   7.6%   ls
     3  24   4.8%   cat
     4  22   4.4%   apt-get
     5  12   2.4%   date
     6  11   2.2%   tail
     7  11   2.2%   cd
     8  10   2%     rm
     9  10   2%     man
    10  9    1.8%   basename

It looks like i use vim a lot on my home server. You should try it yourself and see what commands you use the most.

Source: http://linux.byexamples.com

Apache web connections pr hour

Hans-Henry Jakobsen — Thu, 21 Feb 2008 22:26:15 +0000

This is a bash oneliner to show Apache web connections pr hour. It lists up the IPs that has accessed your webserver and the amount og accesses.

# cat /var/log/apache2/access_log_pario.no | grep "21/Jan/2008:.." | awk {' print $4":"$1 '} | sed 's/\[//g' | awk -F : {' print $1":"$2"\t\t"$5 '} | sort | uniq -c

Example output

37 21/Jan/2008:00          192.168.0.10

This shows that I had 37 hits from 00:00 – 01:00 in 20th February 2008.

Strip the kernel to contain only needed modules

Hans-Henry Jakobsen — Tue, 04 Dec 2007 14:38:45 +0000

This is a great page with som nice bash scripts describing how to remove unwanted modules from your kernel.

Backup mysql databases into separate files

Hans-Henry Jakobsen — Sun, 18 Nov 2007 21:07:39 +0000

This bach script makes separate backup files of all the databases in mysql and saves the result in the mysql_backup folder.

#!/bin/bash -v

USERNAME='yourusername'
PASSWORD='yourpassword'
HOSTNAME='yourhostname'
BackupFolder='/backup'

for i in $(echo 'SHOW DATABASES;' | mysql --user $USERNAME -p$PASSWORD -h $HOSTNAME | grep -v '^Database$' ); do
        mysqldump --user $USERNAME -p$PASSWORD -h $HOSTNAME --opt $i > $BackupFolder/$i.sql;
done;

Remember to change the -h, -p and -h switch according to your needs and avoid space between -p and the password variable.

Grep recursively through subdirectories

Hans-Henry Jakobsen — Thu, 01 Nov 2007 13:54:16 +0000

grep recursively through subdirectories for files that match a specific pattern:

grep -l -r –include=*.doc regex *

The equivalent command unsing find:

find . -name ‘*.doc’ -exec grep -l regex \{\} \;

The option after grep is the lowercase letter L, not the number 1).
Remove the -l to see the actual matches instead of the file names.