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find all active IP addresses in a network
Have to run as superuser... but easier and more informational if you are looking for actual devices. Need to install arp-scan.

Show complete URL in netstat output
The -W switch of netstat makes it print complete URL of the connections, which otherwise by default is truncated to fit its default column size. Now to compensate for irregular column sizes, pipe the output to column (-t switch of column prints in tabular form). The only downside to this part is that the very first row, the header, goes pear shape.

Duplicating service runlevel configurations from one server to another.
And then to complete the task: Go to target host; $ssh host Turn everything off: $for i in `chkconfig --list | fgrep :on | awk '{print $1}'` ; do chkconfig --level 12345 $i off; done Create duplicate config: $while read line; do chkconfig --level $line on; done < foo

Add timestamp to history
History usually only gives the command number and the command. This will add a timestamp to the history file. Note: this will only put the correct timestamp on commands used after the export is done. You may want to put this in your .bashrc

preprocess code to be posted in comments on this site
Assuming that $script contains the filename of a script you'd like to post as part of a comment on this site, this will prefix each line with '$' and pipe it into the X selection. From there just put the cursor in the right place in the comments box and middle-click. Should work pretty much anywhere with xclip installed. On debian-ish systems this is installed as part of the package "xclip".

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Big Countdown Clock in seconds
Requires figlet. Other than that, this should be portable enough across all the Bourne-compatible shells (sh, bash, ksh, zsh, etc). Produces a massive number using figlet that counts down the number of seconds for any given minute interval. For example, here's a 4-minute timer: $ i=$((4*60)); while [ $i -gt 0 ]; do clear; echo $i | figlet; sleep 1; i=$(($i-1)); done; And a 1-minute timer: $ i=$((1*60)); while [ $i -gt 0 ]; do clear; echo $i | figlet; sleep 1; i=$(($i-1)); done;

cut audio file

One command line web server on port 80 using nc (netcat)
Very simple web server listening on port 80 will serve index.html file or whatever file you like pointing your browser at http://your-IP-address/index.html for example. If your web server is down for maintenance and you'd like to inform your visitors about it, quickly and easily, you just have to put into the index.html file the right HTML code and you are done! Of course you need to be root to run the command using port 80.

Install pip with Proxy
Installs pip packages defining a proxy


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