Commands by jearsh (3)

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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"

How to check network connection from one interface
This command only check the network connection from given eth. This is very useful if you are using more then one interface in your server or laptop.

list block devices
Shows all block devices in a tree with descruptions of what they are.

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

Execute a command with a timeout
A timeout is great, but what if the command is taking longer than expected because it's hung up or ran into some other problem? That's where the -k option comes in. Run "some_command" and timeout after 30s. If the command is still running after 1 minute, it will receive a kill signal.

converting vertical line to horizontal line

Display GCC Predefined Macros
doesn't need /dev/null

a simple bash one-liner to create php file and call php function

count and number lines of output, useful for counting number of matches
Write each FILE to standard output, with line numbers added. With no FILE, or when FILE is -, read standard input.

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"


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