#!/usr/bin/env sh result="upstream php {" for x in $(echo $PHP_SERVERS | tr "," "\n"); do parts=$(echo $x | tr "x" "\n") host=$(echo $parts | awk '{print $1}') weight=$(echo $parts | awk '{print $2}') result="$result\n server $host weight=${weight:-1};" done result="$result\n}" echo -e $result > /etc/nginx/conf.d/upstream.conf