Commands by miramir (1)

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Disconnect a wireless client on an atheros-based access point
This command will disconnect the user whose mac was specified from the current list of clients from the wireless network when the network card is working in access point mode. Works on atheros-based access points which use the madwifi driver (not sure, but don't think it will work on access points which are not atheros-based, as it uses the atheros's iwpriv extensions). It will not prevent the user from reconnecting to the network, but may force the user to roam to another AP, with stronger signal.

'hpc' in the box - starts a maximum of n compute commands modulo n controlled in parallel
the block of the loop is useful whenever you have huge junks of similar jobs, e.g., convert high res images to thumbnails, and make usage out of all the SMP power on your compute box without flooding the system. note: c is used as counter and the random sleep $ r=`echo $RANDOM%5 |bc`; echo "sleep $r"; sleep $r is just used as a dummy command.

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"

Insert the last argument of the previous command

The Hidden PS
While going through the source code for the well known ps command, I read about some interesting things.. Namely, that there are a bunch of different fields that ps can try and enumerate for you. These are fields I was not able to find in the man pages, documentation, only in the source. Here is a longer function that goes through each of the formats recognized by the ps on your machine, executes it, and then prompts you whether you would like to add it or not. Adding it simply adds it to an array that is then printed when you ctrl-c or at the end of the function run. This lets you save your favorite ones and then see the command to put in your .bash_profile like mine at : http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html Note that I had to do the exec method below in order to pause with read. t () { local r l a P f=/tmp/ps c='command ps wwo pid:6,user:8,vsize:8,comm:20' IFS=' '; trap 'exec 66

List alive hosts in specific subnet
Works on any machine with nmap installed. Previous version does not work on machines without "seq". Also works on subnets of any size.

list files recursively by size

Do some Perl learning...
Prerequisites: module Pod::Webserver installed. You can install it typing: $ sudo perl -MCPAN -e 'install Pod::Webserver' You can replace elinks with your fav browser. For FF: $podwebserver& sleep 2; firefox -remote 'openurl( http://127.0.0.1:8020/, new-tab )' If you have Firefox open, this will pop-up the index web in a new tab.

Show memory usage of all docker / lxc containers (works on CoreOS)

Benchmark SQL Query
Benchmark a SQL query against MySQL Server. The example runs the query 10 times, and you get the average runtime in the output. To ensure that the query does not get cached, use `RESET QUERY CACHE;` on top in the query file.


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