Commands by houghi (19)

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Put a console clock in top right corner
Gives not only date but also some interesting status about the System

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

For finding out if something is listening on a port and if so what the daemon is.

How to trim a video using ffmpeg
Will trim the video to 4 seconds starting from the beginning. The -vcodec , -acodec options are required so that ffmpeg knows in what video/audio format you want for the new video.

delay execution of a command that needs lots of memory and CPU time until the resources are available
[ 2000 -ge "$(free -m | awk '/buffers.cache:/ {print $4}')" ] returns true if less than 2000 MB of RAM are available, so adjust this number to your needs. [ $(echo "$(uptime | awk '{print $10}' | sed -e 's/,$//' -e 's/,/./') >= $(grep -c ^processor /proc/cpuinfo)" | bc) -eq 1 ] returns true if the current machine load is at least equal to the number of CPUs. If either of the tests returns true we wait 10 seconds and check again. If both tests return false, i.e. 2GB are available and machine load falls below number of CPUs, we start our command and save it's output in a text file. The ( ( ... ) & ) construct lets the command run in background even if we log out. See http://www.commandlinefu.com/commands/view/3115/ .

Get your external IP address ( 10 characters long )
Shortest url to a external IP-service, 10 characters.

Update twitter with Perl
Requires Net::Twitter. Just replace the double quoted strings with the appropriate info.

nmap IP block and autogenerate comprehensive Nagios service checks
More info here: http://nagioswiki.com/wiki/index.php/Autocreating_Nagios_Configuration_with_Nmap_and_Nmap2Nagios.pl

Copy files to a remote host with SFTP with a leading dot, then rename them to the real file name
Usage: $ sftp-cp * | sftp user@host:/dir This is useful if there is a process on the remote machine waiting for files in an incoming directory. This way it won't see half-transmitted files if it ignores hidden files.

Edit 2 or more files in vim using vim -d
Is this not the same


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