Commands by Halki (1)

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Convert all files *.mp4 to *.mpeg using ffmpeg (Windows Cmd line)
Note: %~nI expands %I to a file name only (cf. http://technet.microsoft.com/en-us/library/bb490909.aspx)

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

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"

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Find unused IPs on a given subnet
Somewhat shorter version.

resize all images in a folder

Picture Renamer

remove all snapshots from all virtual machines in vmware esx
Old snapshots can cause problems. It's best to remove them when finished. I use this script to remove all snapshots. The "while read" command is necessary because my vm names contain spaces. The "time" command reports how long the process runs.

Get a diff of two json arrays
jq is amazing for manipulating json on the commandline, but the developers have some weird ideas about how to handle shell redirections. This command works around them. Further reading: https://github.com/stedolan/jq/issues/1110

Create an SSH connection (reverse tunnel) through your firewall.
Allows you to establish a tunnel (encapsulate packets) to your (Server B) remote server IP from your local host (Server A). On Server B you can then connect to port 2001 which will forward all packets (encapsulated) to port 22 on Server A. -- www.fir3net.com --


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