If you're asking which connections your application servers have opened, for debugging or for security reasons, this script provides a nice wrapper around
lsof to display all the IPv4 sockets opened by the processes running as the current user and whose command line matches the regex passed as the first parameter.
Example: here you see four unicorn workers, running on
10.0.0.1 under the
app user, and each of them has a TCP socket open to a database running on port
10.0.0.2, on port
# sudo -u app ~rails/bin/list-my-open-sockets COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME ruby 26010 app 8u IPv4 667051 0t0 TCP 10.0.0.1:47063->10.0.0.2:12345 (ESTABLISHED) ruby 26011 app 8u IPv4 617275 0t0 TCP 10.0.0.1:47064->10.0.0.2:12345 (ESTABLISHED) ruby 26012 app 8u IPv4 664804 0t0 TCP 10.0.0.1:47065->10.0.0.2:12345 (ESTABLISHED) ruby 26013 app 8u IPv4 619068 0t0 TCP 10.0.0.1:47066->10.0.0.2:12345 (ESTABLISHED)
Share & love :-),
#!/bin/sh # # Lists all open IPv4 sockets allocated by the current # user's processes whose command line matches the regex # given as the first parameter. # # Uses "unicorn.*worker" by default, because we all # love unicorns! :-) # # - firstname.lastname@example.org Tue Nov 20 19:06:08 CET 2012 # - https://gist.github.com/4119806 # Get process from the first argument PROC=$1 USER=$(whoami) DEFP="unicorn.*worker" case "$PROC" in -h|--help|--usage) echo "Displays the IPv4 sockets opened by the current user's" echo "processes matching the given regexp (default: \\"$DEFP\\")" echo "Usage: $0 [process regex]" echo exit 1 ;; esac [ -z "$PROC" ] && PROC=$DEFP # Wrap the first letter of the regexp within square brackets, to # avoid `grep` itself coming out in the output. PROC=$(echo $PROC | sed -r 's#(^.)(.*)#[\\1]\\2#') # Get the PIDs matching the resulting regex. PIDS=$(ps -U $USER -o pid,cmd | grep "$PROC" | cut -f1 -d' ' | tr '\\n' ',') # Run! lsof -nP -p $PIDS -a -i4 2>/dev/null # Forward the exit status exit $!