One-Liners

check your ldiretor clients

ipvsadm -L -n

To skip an error on a mysql slave

SET GLOBAL SQL_SLAVE_SKIP_COUNTER = 1;
I always forget that one.

Change the extension of every .html file in your CWD to .php

Rename replaces string X in a set of file names with string Y.
rename 's/.html$/.php/' *.html

Get the env for a running process

ps auxwwe

Rename everything in a dir

perl -e'@files=`ls`; foreach(@files){chomp($_); print `mv $_ $_.ready`;}'

Check for support server SSL/TLS versions

openssl s_client -connect localhost:443

Check for a specific protocol

openssl s_client -host localhost -port 443 -ssl2