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Add a line to a file using sudo
This is the solution to the common mistake made by sudo newbies, since $ sudo echo "foo bar" >> /path/to/some/file does NOT add to the file as root. Alternatively, $ sudo echo "foo bar" > /path/to/some/file should be replaced by $ echo "foo bar" | sudo tee /path/to/some/file And you can add a >/dev/null in the end if you're not interested in the tee stdout : $ echo "foo bar" | sudo tee -a /path/to/some/file >/dev/null

Monitor open connections for httpd including listen, count and sort it per IP
It's not my code, but I found it useful to know how many open connections per request I have on a machine to debug connections without opening another http connection for it. You can also decide to sort things out differently then the way it appears in here.

Get the IP address of a machine. Just the IP, no junk.

SSH connection through host in the middle

get a process list by listen port

Using json.tool from the shell to validate and pretty-print

remove lines which are longer than 255

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"

Advanced python tracing
Trace python statement execution and syscalls invoked during that simultaneously

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


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