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send kernel log (dmesg) notifications to root via cron
this is helpful because dmesg is where i/o errors, etc are logged to... you will also be able to see when the system reboots or someone attaches a thumb drive, etc. don't forget to set yourself up in /etc/aliases to get roots email.

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"

Install pip with Proxy
Installs pip packages defining a proxy

Generate a certificate signing request (CSR) for an existing private key. CSR.csr MUST be exists before
CSR.csr MUST be exists before

Install pip with Proxy
Installs pip packages defining a proxy

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 CSV to JSON - Python3 and Bash function
Based / Inspired by malathion's below command http://www.commandlinefu.com/commands/view/20528/convert-csv-to-json Is written for python3 and is very easy to use csv2json *csv will convert all files ending in csv to json eg csv2json file.csv will output a file to file.json Validity of json tested in python3 and below site https://jsonformatter.curiousconcept.com/

List only directories, one per line

Display the standard deviation of a column of numbers with awk
This will calculate a running standard deviation in one pass and should never have the possibility for overflow that can happen with other implementations. I suppose there is a potential for underflow in the corner case where the deltas are small or the values themselves are small.

Preserve user variables when running commands with sudo.
In this case the current user has proxy variable set which allows access to the rpm on the internet but needs root privs to install it. Running sudo -E preserves the current user proxy var and allows the rpm install to be executed with sudo.


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