Commands by tsaavik

Commands by tsaavik (3)

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Force machine to reboot no matter what (even if /sbin/shutdown is hanging)

This will cause your machine to INSTANTLY reboot. No un-mounting of drives or anything. Very handy when something has gone horribly wrong with your server in that co-location facility miles away with no remote hands! Suspect this works with all 2.2, 2.4 and 2.6 Linux kernels compiled with magic-syskey-request support.
This is sample output - yours may be different.
7

echo 1 > /proc/sys/kernel/sysrq; echo b > /proc/sysrq-trigger

tsaavik · 2009-02-20 00:37:18 1
Run a command if today is the last day of the month

This is handy to just shove into a daily cron entry. If you do use cron, make sure to escape the %d with \%d or it will fail.
This is sample output - yours may be different.
1

if [[ `:$(cal);echo $_` == `date +%d` ]]; then ROTATE_MONTHLY_TABLES_SCRIPT;fi

tsaavik · 2009-02-20 00:28:05 1
ps a process keeping the header info so you know what the columns of numbers mean!

USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND root 1828 0.0 0.0 5396 476 ? Ss 2008 0:00 /usr/sbin/sshd Show Sample Output
This is sample output - yours may be different.
```
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
root      1828  0.0  0.0   5396   476 ?        Ss    2008   0:00 /usr/sbin/sshd
```
4

ps auxw |egrep "PID|process_to_look_at"

tsaavik · 2009-02-20 00:17:43 2

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Show current working directory of a process

Synchronize date and time with a server over ssh

using -u is better for standardizing date output and timezones, for servers in different timezones.

Remove all unused kernels with apt-get

TIMTOWTDI

Rename all .jpeg and .JPG files to have .jpg extension

the "i" controls case sensitiveness. It's slightly inefficient since it uselessly renames .jpg to .jpg, but that's more than compensated by launching only one process instead of two, besides being shorter to write.

Remove a range of lines from a file

Deletes lines from START to END, inclusive. For example +4,10d will delete line 4, 5, ..., 10. Just like the vi command :4,10d does it.

Terminate a frozen SSH-session

A key sequence for terminating a frozen session. Full sequence on a swedish keyboard: [ENTER] [ALTGR] tilde [SPACE] dot

Simulate typing

this also generates errors (change 4 to higher number for more mistakes)

compare two Microsoft Word documents

http://meld.sourceforge.net/ http://www.winfield.demon.nl/

Show database sql schema from Remote or Local database

After ssh into server, run this command to show all the table structure and schema.

Send remote command output to your local clipboard

This command will copy command's output into your local clipboard

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