c:\@Work\Perl\monks>perl -wMstrict -le "use 5.010; ;; my @ra = ( 'session-redis-hosts-fault-tolerant: \"tyk-redis-1.gateways.svc.cluster.local,tyk-redis-2...\"', 'message-center-db: \"http://message-center-db-1b.message-center-db.svc.cluster.local\"', 'a-b-c:d-e-f:g-h-i:j-k', ); ;; for my $s (@ra) { print qq{'$s'}; $s =~ s{ \G [^:]*? \K - (?= [^:]* :) }{_}xmsg; print qq{'$s' \n}; } " 'session-redis-hosts-fault-tolerant: "tyk-redis-1.gateways.svc.cluster.local,tyk-redis-2..."' 'session_redis_hosts_fault_tolerant: "tyk-redis-1.gateways.svc.cluster.local,tyk-redis-2..."' 'message-center-db: "http://message-center-db-1b.message-center-db.svc.cluster.local"' 'message_center_db: "http://message-center-db-1b.message-center-db.svc.cluster.local"' 'a-b-c:d-e-f:g-h-i:j-k' 'a_b_c:d-e-f:g-h-i:j-k'