Commands tagged yaml (14)

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Generate a random password 30 characters long

Use tee to process a pipe with two or more processes
Tee can be used to split a pipe into multiple streams for one or more process to work it. You can add more " >()" for even more fun.

Ping scanning without nmap
Usefull for when you don't have nmap and need to find a missing host. Pings all addresses from 10.1.1.1 to 10.1.1.254, modify for your subnet. Timeout set to 1 sec for speed, if running over a slow connection you should raise that to avoid missing replies. This will clean up the junk, leaving just the IP address: for i in {1..254}; do ping -c 1 -W 1 10.1.1.$i | grep 'from' | cut -d' ' -f 4 | tr -d ':'; done

tell if a port is in use
if you don't do --numeric-ports, netstat will try to resolve them to names

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"

Reuse all parameter of the previous command line
!* is all of the arguments to the previous command rather than just the last one. This is useful in many situations. Here's a simple example: $ vi cd /stuff oops! [exit vi, twice] $ !* expands to: cd /stuff

Test file system type before further commands execution
Exclude 400 client hosts with NFS auto-mounted home directories. Easily modified for inclusion in your scripts.

list block devices
Shows all block devices in a tree with descruptions of what they are.

Periodically run a command without hangups, and send the output to your e-mail
Run "ps -x" (process status) in the background every hour (in this example). The outputs of both "nohup" and "ps -x" are sent to the e-mail (instead of nohup.out and stdout and stderr). If you like it, replace "ps -x" by the command of your choice, replace 3600 (1 hour) by the period of your choice. You can run the command in the loop any time by killing the sleep process. For example $ ps -x 2925 ? S 0:00.00 sh -c unzip E.zip >/dev/null 2>&1 11288 ? O 0:00.00 unzip E.zip 25428 ? I 0:00.00 sleep 3600 14346 pts/42- I 0:00.01 bash -c while true; do ps -x | mail pascalv; sleep 3600; done 643 pts/66 Ss 0:00.03 -bash 14124 pts/66 O+ 0:00.00 ps -x $ kill 25428 You have mail in /mail/pascalv

Use top to monitor only all processes with the same name fragment 'foo'
$ pgrep foo may return several pids for process foobar footy01 etc. like this: 11427 12576 12577 sed puts "-p " in front and we pass a list to top: $ top -p 11427 -p 12576 -p 12577


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