SOLVED: Re: mailq takes 25 sec to respond

[Anton Shterenlikht]

On Fri, Feb 15, 2008 at 11:33:34AM -0500, Bill Moran wrote:
> In response to Anton Shterenlikht <mexas at bristol.ac.uk>:
> 
> > On my ds10l alpha sendmail seem to work fine with the exception
> > of very long wait time for mailq (sendmail -bp) - about 25 sec.
> > 
> > I'm not convinced it is an alpha problem, so I post to this list.
> > 
> > On a much slower i386 running the same version of OS and of sendmail
> > it takes less than a second.
> > 
> > # uname -srm
> > FreeBSD 6.3-STABLE alpha
> > 
> > # sendmail -d0.1
> > Version 8.14.2
> >  Compiled with: DNSMAP LOG MAP_REGEX MATCHGECOS MILTER MIME7TO8 MIME8TO7
> >                 NAMED_BIND NETINET NETINET6 NETUNIX NEWDB NIS PIPELINING SCANF
> >                 TCPWRAPPERS USERDB XDEBUG
> > 
> > The only software difference between my i386 and my alpha I can think of
> > is that on alpha I run IPF:
> > 
> > # grep "= 25" /etc/ipf.rules
> > pass out on dc0 proto tcp from any to any port = 25 flags S/SA keep state
> 
> Based on your description of the probem, you should ensure that all
> block rules in ipf include logging, and see if running mailq is triggering
> a timeout because it can't communicate over the network.  25 sec is
> suspiciously close to 30 seconds, which is a common timeout value for
> network operations.
> 
> sendmail needs to communicate on more ports than just 25, so it's
> likely that you've blocked something else that it needs ... DNS perhaps?

I solved it first reading http://www.goldfisch.at/knowledge/70 :

	"If sendmail takes very long time for starting and
	output of mailq takes many seconds, than you might
	have a name-resolve-problem. Check logfiles for
	gethostbyaddr ... failed - entries and fix corresponding
	resolve-problem."

which is what I did:

% grep gethostbyaddr /var/log/maillog
Feb 15 03:01:23 <myhostname> sendmail[71810]: gethostbyaddr(10.10.10.1) failed: 2
Feb 15 03:01:58 <myhostname> sendmail[71856]: gethostbyaddr(10.10.10.1) failed: 2
Feb 15 03:02:40 <myhostname> sendmail[72061]: gethostbyaddr(10.10.10.1) failed: 2
% 

I then found why I get this error, from http://www.sunhelp.org/faq/sendmail.html

	"QUESTION: Why does my Solaris machine generate the error
		"sendmail: gethostbyaddr failed" whenever I send mail? 

	ANSWER: One of more of the IP addresses configured on your
		system does not have a matching entry in /etc/hosts.
		sendmail does a "reverse" lookup (input IP address,
		output hostname) when it starts up, generating the
		error. You can either fix /etc/host and your Nameservice,
		or ignore the message."

Although I had an entry for the second ethernet port (10.10.10.1) in
/etc/rc.conf, I didn't have it in /etc/hosts.

I fixed /etc/hosts and all is fine now.

many thanks
anton
 
-- 
Anton Shterenlikht
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