Marten Lehmann wrote:
> Hello,
>
> I'm using dnslists to check against RBLs and it works fine most of the
> time. But sometimes the DNS lookups seem to take too long so for the
> client it seems as if our SMTP-server is not responding and then it
> timeouts the request. Is there a way to set a timeout and when the RBL
> nameservers couldn't be contacted it will be treated as if there is no
> entry in the RBL list?
>
> Regards
> Marten
>
I cannot find anything specific in:
http://exim.org/exim-html-4.63/doc/html/spec_html/ch39.html#SECTmorednslists
- Unless the 'general' options for callouts might apply..
But there is already a very reasonable default that does just what you asked for.
Entries such as those below may not show for many days, then run for an hour in
a burst of *many*, other days one to four only for the entire day, etc.
2006-10-21 13:19:32 DNS list lookup defer (probably timeout) for
113.249.106.85.dnsbl.njabl.org: assumed not in list
2006-10-21 15:11:51 DNS list lookup defer (probably timeout) for
1.13.243.168.dul.dnsbl.sorbs.net: assumed not in list
2006-10-21 15:14:43 DNS list lookup defer (probably timeout) for
1.13.243.168.xbl.spamhaus.org: assumed not in list
Some of the spikes were time-associated with upstream DNS maintenance.
The code has just a 'vanilla' call, such as:
dnslists = dul.dnsbl.sorbs.net
Grep for 'DNS list lookup defer' in your logs?
Bill