Re: [opensuse] Reverse DNS of slave server (was : "Slow" postfix)

Sandy Drobic schreef:
Koenraad Lelong wrote:
Hi,
My postfix mail-server is slow to wake up. Between the setup of the
tcp-connection (SYN/SYN-ACK/ACK) and the response "220 ..." there are at
least 10 seconds. I (and my users) find this annoying.

Fix your dns server.

When a client connects to your mailserver, Postfix will do a reverse lookup of
the client ip and a forward lookup of the result of the reverse lookup. Most
probably your dns can't resolve the client ips correctly and tries until it
times out.

One sign of this is that your clients are logged as "unknown" instead of the
correct hostnames.

A mailserver relies heavily on DNS, correctly working DNS is a must.

It's indeed a problem of DNS, more specific the reverse DNS. The mailserver is also a slave DNS-server. This seems unable to resolve reverse dns-queries. It times out, and then the mailserver qeuries the master dns-server that answers promptly it can't find the host, which is understandable since my local users don't have dns-entries.
So it boils down to : why does reverse resolving not work when forward resolving does work ?
Suggestions ? I will search the net in the mean time.
--
Met vriendelijke groeten,
Koenraad Lelong begin:vcard
fn:Koenraad Lelong
n:Lelong;Koenraad
org:ACE electronics
adr:;;IZ Webbekom 2118;Diest;VlaBra;3290;Belgie
email;internet:k.lelong@xxxxxxxxxxxxxxxxxx
title:R&D Manager
tel;work:+32 13 531906
tel;fax:+32 13 531908
x-mozilla-html:FALSE
url:www.ace-electronicss.be
version:2.1
end:vcard

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