Ignore errors to do with refreshing instance firewall

Seems to be a race condition and is causing errors in
logs for no reason.
This may be due to cells or somethign that is fixed on icehouse

Change-Id: I861339f1857078586cc527f00a8859db7abdbb13
Set unique hostnames when launching multiple instances

Change-Id: I5bef77aff24c35dcff1e993034e34cd87e672186