Sendmail pids living a long time

I have a bank of very busy MX (gateway) servers and have been seeing the following sceanerio. This is an excerpt of a ps -axu list on a server that
maintains 300-500 processesses at any given time. The same thing happens on others.

Note that today is Tuesday, Dec 4.at 1300 CDT. Look at the age of the following processes.

root 74171 0.0 0.1 4180 3028 ?? S 9:23AM 0:20.28 sendmail: server mum-svr-mta-out-02.bsnl.net.in [218.248.240.203] (m
root 76482 0.0 0.1 3888 2480 ?? I Fri10AM 0:00.01 sendmail: lAUGjj7M076482 [85.93.179.163]: HELO outremer.com (sendmai
root 79213 0.0 0.1 3916 2776 ?? I 12:29PM 0:00.18 sendmail: lB4IT9vH079213 [88.245.174.121]: RCPT TO: root 79705 0.0 0.1 3920 2544 ?? I Mon06AM 0:00.03 sendmail: lB3CgNXK079705 trip20.paradeget.com [216.74.90.20]: RCPT T
root 81396 0.0 0.1 3884 2460 ?? I Fri07AM 0:00.01 sendmail: lAUDVrM1081396 pool-71-179-6-13.bltmmd.fios.verizon.net [7
root 85315 0.0 0.1 3896 2548 ?? I Sat01AM 0:00.01 sendmail: lB17Qpdu085315 53.11.33.65.cfl.res.rr.com [65.33.11.53]: R
root 87081 0.0 0.1 3932 2488 ?? I Fri11AM 0:00.01 sendmail: lAUHr8J5087081 41-51.126-70.tampabay.res.rr.com [70.126.51
root 89060 0.0 0.1 3896 2500 ?? I Fri04PM 0:00.02 sendmail: lAUM7TJk089060 host-196-205-94-75.static.link.com.eg [196.
root 89344 0.0 0.1 3896 2500 ?? I Fri07PM 0:00.01 sendmail: lB112XOu089344 [200.77.144.203]: RCPT TO: root 91510 0.0 0.1 3904 2528 ?? I Sat08PM 0:00.01 sendmail: lB22DS90091510 [194.219.45.197]: RCPT TO: root 92334 0.0 0.1 3884 2460 ?? I Fri09AM 0:00.01 sendmail: lAUFoH5i092334 pool-68-239-14-11.bos.east.verizon.net [68.
root 93388 0.0 0.1 3900 2520 ?? I Sat04PM 0:00.01 sendmail: lB1MtnfF093388 dsl-189-142-64-25.prod-infinitum.com.mx [18

I am running the following:
FreeBSD 6.2 Release
Sendmail 8.14.2
Milter-Ahead 1.8
Clamav-Milter 0.92rc2
--
David L. Aldridge
The Aldridge Company 713-403-9150 (fax: 713-621-1826)
http://www.aldridge.com/
Powered by Pentium/FreeBSD/Apache - Because it works.

Re: Sendmail pids living a long time

David L. Aldridge writes:

> I have a bank of very busy MX (gateway) servers and have been seeing the following sceanerio. This is an excerpt of a ps -axu list on a server that
> maintains 300-500 processesses at any given time. The same thing happens on others.
>
> Note that today is Tuesday, Dec 4.at 1300 CDT. Look at the age of the following processes.
>
> root 74171 0.0 0.1 4180 3028 ?? S 9:23AM 0:20.28 sendmail: server mum-svr-mta-out-02.bsnl.net.in [218.248.240.203] (m
> root 76482 0.0 0.1 3888 2480 ?? I Fri10AM 0:00.01 sendmail: lAUGjj7M076482 [85.93.179.163]: HELO outremer.com (sendmai
> root 79213 0.0 0.1 3916 2776 ?? I 12:29PM 0:00.18 sendmail: lB4IT9vH079213 [88.245.174.121]: RCPT TO: > root 79705 0.0 0.1 3920 2544 ?? I Mon06AM 0:00.03 sendmail: lB3CgNXK079705 trip20.paradeget.com [216.74.90.20]: RCPT T
> root 81396 0.0 0.1 3884 2460 ?? I Fri07AM 0:00.01 sendmail: lAUDVrM1081396 pool-71-179-6-13.bltmmd.fios.verizon.net [7
> root 85315 0.0 0.1 3896 2548 ?? I Sat01AM 0:00.01 sendmail: lB17Qpdu085315 53.11.33.65.cfl.res.rr.com [65.33.11.53]: R
> root 87081 0.0 0.1 3932 2488 ?? I Fri11AM 0:00.01 sendmail: lAUHr8J5087081 41-51.126-70.tampabay.res.rr.com [70.126.51
> root 89060 0.0 0.1 3896 2500 ?? I Fri04PM 0:00.02 sendmail: lAUM7TJk089060 host-196-205-94-75.static.link.com.eg [196.
> root 89344 0.0 0.1 3896 2500 ?? I Fri07PM 0:00.01 sendmail: lB112XOu089344 [200.77.144.203]: RCPT TO: > root 91510 0.0 0.1 3904 2528 ?? I Sat08PM 0:00.01 sendmail: lB22DS90091510 [194.219.45.197]: RCPT TO: > root 92334 0.0 0.1 3884 2460 ?? I Fri09AM 0:00.01 sendmail: lAUFoH5i092334 pool-68-239-14-11.bos.east.verizon.net [68.
> root 93388 0.0 0.1 3900 2520 ?? I Sat04PM 0:00.01 sendmail: lB1MtnfF093388 dsl-189-142-64-25.prod-infinitum.com.mx [18
>
> I am running the following:
> FreeBSD 6.2 Release
> Sendmail 8.14.2
> Milter-Ahead 1.8
> Clamav-Milter 0.92rc2

0) Have you measured "reply time" for a few (2-3) "RCPT TO:" commands
listed above?
I remember a few "ugly" problems with long reply times.
1) Have you tried to fine tune Timeout.* settings in sendmail.cf?
e.g. down to RFC recommended minimums
grep "^O Timeout" /etc/mail/sendmail.cf
2) Have you considered to reduce "TCP level" keepalive timeout?
AFAIR default is 2h, I think it should be lowered to 10m on busy
mail server

AFAIK sendmail does not support "connection drop" in RFC permitted way.
[ sending reply to anticipated next command ]. Am I wrong?

--
[pl>en: Andrew] Andrzej Adam Filip : anfi@priv.onet.pl : anfi@xl.wp.pl
Open-Sendmail: http://open-sendmail.sourceforge.net/

TCP Keepalive Option (was Re: Sendmail pids living a long time)

Andrzej Adam Filip wrote:

> 2) Have you considered to reduce "TCP level" keepalive timeout?
> AFAIR default is 2h, I think it should be lowered to 10m on busy
> mail server

On many systems the TCP keepalive setting is system-wide and affects
*every* TCP connection on the machine. It's not a good idea to adjust
it unless you really know what you're doing, and definitely not for
Sendmail problems because it's much better adjust Sendmail's timeouts.

> AFAIK sendmail does not support "connection drop" in RFC permitted way.
> [ sending reply to anticipated next command ]. Am I wrong?

I'm not sure. I believe recent Sendmails will drop the connection if a milter
returns 421.

Regards,

David.

Re: TCP Keepalive Option

"David F. Skoll" writes:

> Andrzej Adam Filip wrote:
>
>> 2) Have you considered to reduce "TCP level" keepalive timeout?
>> AFAIR default is 2h, I think it should be lowered to 10m on busy
>> mail server
>
> On many systems the TCP keepalive setting is system-wide and affects
> *every* TCP connection on the machine.
> It's not a good idea to adjust it unless you really know what you're
> doing, and definitely not for Sendmail problems because it's much
> better adjust Sendmail's timeouts.

I fully agree with your "unless" clause and I agree mostly with
"definitely" part *BUT* IMHO lowering TCP Keepalive Option stays as
a reasonably good idea on *big* mail servers facing *modern quality*
Internet.

> [...]

--
[pl>en: Andrew] Andrzej Adam Filip : anfi@priv.onet.pl : anfi@xl.wp.pl
Open-Sendmail: http://open-sendmail.sourceforge.net/