Tony, I know the subject is provocative, but I'm afraid I have no better way to describe it. Short version: If you use host=some.dns.name or register => user:pass@some.dns.name/fneh then you're liable to have chan_sip die under you should some.dns.name die (ie, all DNS servers authoritative for that name become unreachable and you keep getting timeouts on them). In my particular case sip.iburst.co.za for which I have 16 register => lines and one host= peer went awol, taking chan_sip with. No fix from upstream yet (obviously). I have a work-around. Figured I'd post the bug here so long to ensure that you're aware of this. It affects all asterisk-11.* installs as far as I can determine (design flaw). Reproducible: Always