Commands using ssh (347)

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Set all CPU cores' CPU frequency scaling governor to maximum performance

Watch the progress of 'dd'
dcfldd is a forensic version of dd that shows a process indicator by default.

Display disk partition sizes

Add all files
Add all files

After typing lots of commands in windows, save them to a batch file quickly
After typing the command below, you will be greeted with nothing. press the up arrow to find the previous command you typed, press enter. repeat this as many times as you need, then hit CTRL-Z and press enter to save to the 'batchfilename.bat' file.

View ~/.ssh/known_hosts key information
Will return the SSH server key information for each host you have in your ~/.ssh/known_hosts file, including key size, key fingerprint, key IP address or domain name, and key type.

Repeatedly purge orphaned packages on Debian-like Linuxes
Upgraded Debian/Ubuntu/etc. systems may have a number of "orphaned" packages which are just taking up space, which can be found with the "deborphan" command. While you could just do "dpkg --purge $(deborphan)", the act of purging orphans will often create more orphans. This command will get them all in one shot.

Report full partitions from a cron
Reports all local partitions having more than 90% usage. Just add it in a crontab and you'll get a mail when a disk is full. (sending mail to the root user must work for that)

Print all environment variables, including hidden ones
This uses some tricks I found while reading the bash man page to enumerate and display all the current environment variables, including those not listed by the 'env' command which according to the bash docs are more for internal use by BASH. The main trick is the way bash will list all environment variable names when performing expansion on ${!A*}. Then the eval builtin makes it work in a loop. I created a function for this and use it instead of env. (by aliasing env). This is the function that given any parameters lists the variables that start with it. So 'aae B' would list all env variables starting wit B. And 'aae {A..Z} {a..z}' would list all variables starting with any letter of the alphabet. And 'aae TERM' would list all variables starting with TERM. $ aae(){ local __a __i __z;for __a in "$@";do __z=\${!${__a}*};for __i in `eval echo "${__z}"`;do echo -e "$__i: ${!__i}";done;done; } And my printenv replacement is: $ alias env='aae {A..Z} {a..z} "_"|sort|cat -v 2>&1 | sed "s/\\^\\[/\\\\033/g"' From: http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

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"


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