Commands by petiteabeille (2)

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Check for login failures and summarize
This command checks for the number of times when someone has tried to login to your server and failed. If there are a lot, then that user is being targeted on your system and you might want to make sure that user either has remote logins disabled, or has a strong password, or both. If your output has an "invalid" line, it is a summary of all logins from users that don't exist on your system.

Exclude inserting a table from a sql import
Starting with a large MySQL dump file (*.sql) remove any lines that have inserts for the specified table. Sometimes one or two tables are very large and uneeded, eg. log tables. To exclude multiple tables you can get fancy with sed, or just run the command again on subsequently generated files.

Start a new command in a new screen window
If you are already running screen then you often want to start a command in a fresh window. You use this alias by typing 's whatever' from your command line and 'whatever' starts running in a new window. Good with interactive commands like info, vim, and nethack.

Display the top ten running processes - sorted by memory usage
ps returns all running processes which are then sorted by the 4th field in numerical order and the top 10 are sent to STDOUT.

Print a single route to a destination and its contents exactly as the kernel sees it
Useful to determine the source_ip of outgoing packages to a certain destination

Sets shell timeout
Useful in root's .profile - will auto-logout after TMOUT seconds of inactivity. Close after `seconds` inactive. export TMOUT=seconds (unefunge)

Split a tarball into multiple parts
Create a tar file in multiple parts if it's to large for a single disk, your filesystem, etc. Rejoin later with `cat .tar.*|tar xf -`

Protect directory from an overzealous rm -rf *
-R Recursively change attributes of directories and their contents. +i to set the immutable bit to prevent even root from erasing or changing the contents of a file.

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"

reverse order of file

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