Commands by Iz7ueNae (2)

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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

Limit memory usage per script/program
When I'm testing some scripts or programs, they end up using more memory than anticipated. In that case, computer nearly halts due to swap space usage, and sometimes I have to press Magic SysRq+REISUB to reboot. So, I was looking for a way to limit memory usage per script and found out that ulimit can limit memory. If you run it this way: $ $ ulimit -v 1000000 . $ $ scriptname Then the new memory limit will be valid for that shell. I think changing the limit within a subshell is much more flexible and it won't interfere with your current shell ulimit settings. note: -v 1000000 corresponds to approximately 1GB of RAM

Display error pages in report format
This command will return a full list of Error 404 pages in the given access log. The following variables have been given to awk Hostname ($2), ERROR Code ($9), Missing Item ($7), Referrer ($11) You can then send this into a file (>> /path/to/file), which you can open with OpenOffice as a CSV

Find installed network devices
Find installed network devices.

Directory Tree
tree has lots of parms - man is your friend

List only directories, one per line
omit the 1 (one) if you don't need one-per-line

Convert JSON to YAML
Requires installing json2yaml via npm: npm install -g json2yaml (can also pipe from stdin) Ref: https://www.npmjs.com/package/json2yaml

get a fresh commandlinefu-item each day as motd
Commandline-fu often has little tricks that I always forget. By adding this to the root-cron (sudo crontab -e) I lean a new trick every day.

Stream audio over ssh ogg version
Stream OGG vorbis over ssh.

Easily search running processes (alias).


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