Commands by unixmonkey6280 (1)

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Anti DDOS
Takes IP from web logs and pipes to iptables, use grep to white list IPs.. use if a particular file is getting requested by many different addresses. Sure, its already down pipe and you bandwidth may suffer but that isnt the concern. This one liner saved me from all the traffic hitting the server a second time, reconfigure your system so your system will work like blog-post-1.php or the similar so legitimate users can continue working while the botnet kills itself.

Download a numbered sequence of files

find all file larger than 500M

doing some floating point math

Top 20 commands in your bash history

gpg decrypt a file
gpg command to decrypt a previously encrypted file on the command line. Can be optionally made into an alias: alias decrypt='gpg --output foo.txt --decrypt foo.txt.pgp'

List known debian vulnerabilities on your system -- many of which may not yet be patched.
You can search for CVEs at https://security-tracker.debian.org/tracker/ or use --report to get full links. This can be added to cron, but unless you're going to do manual patches, you'd just be torturing yourself.

Remove blank lines from a file using grep and save output to new file
The ^$ within the quotes is a regular expression: ^=beginning of line, $=end of line, with no characters between.

Find the package that installed a command

Extract audio from a video
With the -vn switch we make our intentions clear and ask FFmpeg not to bother itself with the video. Next we specify the audio codec copy, which tells FFmpeg to use the same codec to encode the audio, which it uses to decode it. To keep things simple, we'll just keep the sampling and bitrate values the same.


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