Commands by TeacherTiger (5)

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Simple XML tag extract with sed
Limited, but useful construct to extract text embedded in XML tags. This will only work if bar is all on one line. If nobody posts an alternative for the multiline sed version, I'll figure it out later...

Get a BOFH excuse
Gets a BOFH excuse from the BOFH excuse server (towel.blinkenlights.nl port 666), and passes it through sed and tr to get rid of telnet connection stuff.

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

Convert control codes to visible Unicode Control Pictures
Converts control codes and spaces (ASCII code ≤ 32) to visible Unicode Control Pictures, U+2400 ? U+2420. Skips \n characters, which is probably a good thing.

Check for Firewall Blockage.
This is just one method of checking to see if an IP is blocked via IP tables or CSF. Simple and to the point. Replace xx.xx.xx.xx with the IP you wish to check.

Dump a configuration file without comments or whitespace...
A short, *easy-er* to remember command for stripping whitespace and comments from a config file, (or any file for that matter). Remember regex as: slash, space, star. pound, slash, bar. pointy-hat, dollar. (or "caret, dollar" if you must) :-P

renames multiple files that match the pattern
Useful when you want to quickly rename a bunch of files.

Synchronize both your system clock and hardware clock and calculate/adjust time drift
Do not run this command if you already have ntpd running! This needs to run as root, for example with sudo: $ sudo ntpdate pool.ntp.org && sudo hwclock --systohc && sudo hwclock --adjust This command will fetch accurate time from NTP servers and synchronize your system clock, then it will use the system clock to synchronize your hardware clock, and will calculate the time drift.

list files recursively by size

Blacklist usb storage
Some times you may ban usb to protect thefting of your personal data. Blacklist the usb_storage module by adding blacklist usb_storage to /etc/modprobe.d/blacklist.conf. To load the module manually, $sudo modprobe usb_storage.


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