Commands by unixmonkey14859 (9)

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check open ports without netstat or lsof

Determine MAC address of remote host when you know its IP address
arping sends ARP requests to a neighboring host. This won't work if there is an ARP subnet gateway in the middle. If there is, you'll just get the gateway's MAC address not the host's address you are really trying to get to.

Random Number Between 1 And X
If X is 5, it will about a number between 1 and 5 inclusive. This works in bash and zsh. If you want between 0 and 4, remove the +1.

Look for English words in /dev/urandom
* to get the English dictionary: wget http://www.mavi1.org/web_security/wordlists/webster-dictionary.txt

quickly change all .html extensions on files in folder to .htm

Find ulimit values of currently running process
When dealing with system resource limits like max number of processes and open files per user, it can be hard to tell exactly what's happening. The /etc/security/limits.conf file defines the ceiling for the values, but not what they currently are, while $ ulimit -a will show you the current values for your shell, and you can set them for new logins in /etc/profile and/or ~/.bashrc with a command like: $ ulimit -S -n 100000 >/dev/null 2>&1 But with the variability in when those files get read (login vs any shell startup, interactive vs non-interactive) it can be difficult to know for sure what values apply to processes that are currently running, like database or app servers. Just find the PID via "ps aux | grep programname", then look at that PID's "limits" file in /proc. Then you'll know for sure what actually applies to that process.

VMware Server print out the state of all registered Virtual Machines.
I use this command on my machines running VMware Server to print out the state of all registered Virtual machines.

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"

Outputs files with ascii art in the intended form.
Files containing ascii art (e.g. with .nfo extension) are typically not correctly reproduced at the command line when using cat. With iconv one can easily write a wrapper to solve this: $ #!/bin/bash $ if [ -z "$@" ]; then echo "Usage: $(basename $0) file [file] ..." $ else iconv -f437 -tutf8 "$@"; fi $ exit 0

Lists all files and directories with modified time newer than a given date
This is great for looking for files that have been updated recently. Logs especially or monitoring what files were added during an install.


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