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sort ip by count quickly with awk from apache logs
creates associative array from apache logs, assumes "combined" log format or similar. replace awk column to suit needs. bandwidth per ip is also useful. have fun. I haven't found a more efficient way to do this as yet. sorry, FIXED TYPO: log file should obviously go after awk, which then pipes into sort.

Arguments too long

Do quick arithmetic on numbers from STDIN with any formatting using a perl one liner.
Good for summing the numbers embedded in text - a food journal entry for example with calories listed per food where you want the total calories. Use this to monitor and keep a total on anything that ouputs numbers.

Kill a broken ssh connection
This is useful for example if you are on ssh in a server and the server goes down without letting you out. This is part of a larget sets of escape sequences provided by ssh. You can find them with ~? Here's the list: ~. - terminate connection (and any multiplexed sessions) ~B - send a BREAK to the remote system ~C - open a command line ~R - request rekey ~V/v - decrease/increase verbosity (LogLevel) ~^Z - suspend ssh ~# - list forwarded connections ~& - background ssh (when waiting for connections to terminate) ~? - this message ~~ - send the escape character by typing it twice (Note that escapes are only recognized immediately after newline.)

Create a local compressed tarball from remote host directory
The command uses ssh(1) to get to a remote host, uses tar(1) to archive a remote directory, prints the result to STDOUT, which is piped to gzip(1) to compress to a local file. In other words, we are archiving and compressing a remote directory to our local box.

Quickly generate an MD5 hash for a text string using OpenSSL

Find the package that installed a command

Create md5sum of a directory

add repeated watermark to image

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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