Re: lame reverse DNS?

On Thu, 27 Feb 2020 16:56:55 +0100 Herbert J. Skuhra herbert_at_gojira.at said

> On Thu, Feb 27, 2020 at 10:31:59AM +0100, Kurt Jaeger wrote:
> > Hi!
> > 
> > > The problem has been resolved but I still sometimes see "connect from
> > > unknown[2610:1c1:1:606c::19:2]" in the maillog (today: 6 of 131
> > > connections). Local unbound issue?
> > 
> > That IPv6 has a valid reverse DNS record, so please try to investigate.
> 
> Yes, I know. Otherwise it would fail permanently.
> 
> - Postfix sends two standard queries (PTR) to local unbound within 5
> seconds (05:51:23 and 05:51:28)
> - Unbound sends multiple queries to 2610:1c0::1104 and 2610:1c0::1204
> without receiving a reply (05:51:23 - 05:51:41)
> - Unbound replies twice with Server failure (05:51:53)
> 
> I have this issue only with [2610:1c1:1:606c::19:2]:
> 
> # grep " connect from unknown" /var/log/maillog
> Feb 27 03:37:53 mail postfix/smtpd[93921]: connect from
> unknown[2610:1c1:1:606c::19:2]
> Feb 27 08:40:27 mail postfix/smtpd[33354]: connect from
> unknown[2610:1c1:1:606c::19:2]
> Feb 27 09:43:39 mail postfix/smtpd[41982]: connect from
> unknown[2610:1c1:1:606c::19:2]
> Feb 27 10:53:38 mail postfix/smtpd[4960]: connect from
> unknown[2610:1c1:1:606c::19:2]
> Feb 27 15:30:28 mail postfix/smtpd[87816]: connect from
> unknown[2610:1c1:1:606c::19:2]
> Feb 27 15:50:30 mail postfix/smtpd[98816]: connect from
> unknown[2610:1c1:1:606c::19:2]
> 
> I've already set cache-min-ttl to 3600. FreeBSD.org uses ttl=60. Why?
> I'll try to set do-ip6=no. Meanwhile I've whitelisted the IPv6 address
> in postfix. 
> 
FWIW I thought I might chime in here to report that I'm also seeing
*periodic* failures.
IOW lookups fail, but aren't *completely* fatal. :)

--Chris
FreeBSD 14.0-FUTURE #0.000 cray256

> -- 
> Herbert
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