On Feb 23, 2011, at 11:16 AM, Victor Duchovni wrote: > On Wed, Feb 23, 2011 at 01:09:24PM -0600, Noel Jones wrote: > >> For the same destination, postfix will remember a dead host across multiple >> messages, and not retry a known dead host for a period of time. > > No. Postfix remembers dead destinations, not dead hosts. When a live > destination is served by hosts a subset of which are down, demand > connection caching kicks in under load and reduces the frequency > of (probabilistically slow) connection attempts. > > -- > Viktor.
I guess I'm most interested in what happens when a backoff response is sent back from my edge (relayhost/smarthost) MTA to my origin MTA. Since this is not a dead MX we're talking about, I'm trying to understand the negotiation and see if rapidly-expiring internal DNS TTL would actually _do_ anything or just shake up the randomization, which is pointless.
