A quick and dirty CCM ethernet aliasing program

ccm_eth_alias_listener.sh

#!/bin/bash

# -------------------------------------
# Quick and dirty to set up cassandra
# CCM with alias'ed ethernet addresses
# -------------------------------------
#

# ===== #
# ARGS  #
# ===== #
#
# The only argument is location of .ccm directory

EXPECTED_ARGS=1

[ x$1 == "x-h" ] || [ x$1 == "x--help" ] || [ $# -gt $EXPECTED_ARGS ] && \
       echo && \
       echo "USAGE FOR $0" && \
       echo "===============================================================================================" && \
       echo "$0 <location of .ccm directory - USUALLY ~/>" && \
       echo && \
       echo "  example:    $0" && \
       echo "              $0 ~/" && \
       echo "              $0 /opt/ccm/.ccm" && exit

[ "$1" ] && DIR="$1/.ccm" || DIR="$HOME/.ccm"

# ========== #
# PROGRAM    #
# ========== #
#

# The interface that is aliased
ETH=$(ifconfig -a | grep -oP '^\w+(?=:\d)' | uniq)

for yaml in $(find $DIR/$(cat $DIR/CURRENT)/ -name cassandra.yaml); do
	nodenum=$(echo $yaml | grep -oP '(?<=node)\d+')
	address=$(ifconfig $ETH:$nodenum | grep -oP '(?<=addr:)(\d+\.)+\d+(?=\s)')
	sed -i "/listen_address:/c\listen_address:$address" $yaml
      	echo "CHANGED NODE $nodenum ($yaml) TO LISTEN ON: $address"
done