On Fri, Apr 27, 2012 at 10:58:32AM -0700, kar...@mailcan.com wrote: > On Fri, Apr 27, 2012, at 01:47 PM, Wietse Venema wrote: > > > I'd still think that a local check by Postfix to an 'auto-expiring hash > > > table' (unclear so far it that can be done) to which the 'bad' address > > > > Each Postfix SMTP server caches its own DNSBL lookup results. Those > > results are not shared with other Postfix processes.
This is nice, I didn't knew about this. > > The in-process cache saves time when one message has multiple > > recipients, and the DNSBL check is done once per recipient in > > smtpd_recipient_restrictions. > > Does a single "Postfix SMTP server" process instance remain > resident/open across multiple connections? Or is a new one spawned for > each connection, or perhaps after some delay, load or other trigger? > > If it's the former, and I understand this right, then the two > somewhat-concurrent connections from the same spamhaus-banned IP, as > referenced in my OP, > > Apr 26 11:13:07 liam postfix/smtpd[22946]: connect from [..] > Apr 26 11:13:32 liam postfix/smtpd[22946]: connect from [..] > ARE using the Postfix 'internal' DNSBL cache? How do I learn/observe > that use of the cached value from logs? You can observe the PID (22946 in this case). If it is the same, the in process cache will be hit. Dennis [..]