topic Re: sendmail limits .. ?? in Operating System - HP-UX

sendmail limits .. ??

someone_4 — Fri, 07 Dec 2001 18:19:07 GMT

Hey everyone
I have a question about sendmail limits. I have a mailserver running sendmail 8.8.6 ... cant upgrade do to a ldapux issues. But thats another story. I just did a count today and got back that we have 3764 email files in /var/mail. Now I didnt set this up so I dont know why it was set up the way it was. But if I was doing this from scratch I would have tried to get 2 mailsevers to share the work for the 1 domain. (lemme know if I am thinking right by that ) But anyways I have been asked/told that I am respobsible for this mailserver. So now I need to find out what the best things I could do to get this puppy running the best with what I have. Some of the things I am seeing here is Deferred: Connection timed to several domains,allot of (no control file)

Re: sendmail limits .. ??

someone_4 — Fri, 07 Dec 2001 18:20:38 GMT

posted too soon. sorry ..
so my other question is what are the limits that I can push this bad boy to? What do I need to look at? and are there any good tweeks that I can do to the sendmail.cf file that will make it run smoother without having to upgrade sendmail.
Thanks
richard

Re: sendmail limits .. ??

Christopher Caldwell — Fri, 07 Dec 2001 18:31:18 GMT

I'm not sure about your particular problem, but - as far as sendmail is concerned, limits are based on strength of the host and sendmail topology.

I've got a sendmail server on an E55 with about 7500 accounts and a reasonable mail volume:

$ mailstats
Statistics from Tue Sep 29 19:27:05 1998
M msgsfr bytes_from msgsto bytes_to Mailer
0 0 0K 535296 4573484K prog
1 0 0K 5307 18162K *file*
3 6102158 490526454K 17414571 320074061K local
5 19509245 468247985K 8103977 236967037K esmtp
9 16 86K 3 37K uucp-old
========================================
T 25611419 958774525K 26059154 561632781K

You're main consideration with sendmail is disk I/O. Think about striping /var/mail across multiple physical drives. If you're really ambitious, you can hash the /var/mail directory.

When you go to scale, think about separating the spindles for /var/mail, /var/spool/mqueue, and your pop directory if your using POP3. All three directories should be striped and on different spindle sets.

To scale farther, think about separating the recieving, sending, and delivering functions, so that all inbound mail hits server 1 for processing (so you can virus filter or apply anti-SPAM rulesets like RBL). Deliver to the box clients access. Have clients send through yet another box.

When you get really sophisticated, you can have multiple recievers deliver to multiple deliverers (perhaps organized in alpha order or by departments) and multiple outbound hosts.

etc.

Re: sendmail limits .. ??

Christopher Caldwell — Fri, 07 Dec 2001 18:35:41 GMT

BTW, the server in the example has 919 virt domains and relays for a fair number of other domains.

Re: sendmail limits .. ??

someone_4 — Fri, 07 Dec 2001 18:40:35 GMT

Here is snapshot of my glance screen.

Re: sendmail limits .. ??

Christopher Caldwell — Fri, 07 Dec 2001 18:45:36 GMT

send a cut of top. BTW, the single biggest thing we did to improve performance was striping drives and separating spindles.

It turns out that the checking contends a lot with recieving/sending/delivering process.

Re: sendmail limits .. ??

James R. Ferguson — Fri, 07 Dec 2001 18:47:51 GMT

Hi Richard:

A quick glance at your glance data [pun intended ;-)] shows your swap utilization is quite high. I'd add some more device swap.

Also, your buffer cache appears to be quite large. Depending on *your* performance and on *your* environment, you might want to scale this back.

Regards!

...JRF...

Re: sendmail limits .. ??

Mark Greene_1 — Fri, 07 Dec 2001 18:49:50 GMT

you can do a 'mailq -v -d' to see some of the basic config information, and any errors the debugger might turn-up.

You did not say, but is all of the mail in /var/mail for root, or is it for multiple id's? You can reduce the load of root e-mail by making sure all of your cron processes are directing standard error to a log file rather than to root's mail. You can also see about implementing a policy for your users about how long mail can sit on the system after it's been read.

--
mark

Re: sendmail limits .. ??

Sachin Patel — Fri, 07 Dec 2001 18:53:30 GMT

Hi Richard,
The way we have sendmail is
one 712 mailserver with 20gb disk. It collects unix mail from all the unix systems and send them to notes server.
- our aliases file is look like this
sachin: sachin_patel
sachin_patel: sachin_patel@smt-mt.veritasdgc.com

#nslookup smt-mt is lotus notes server.

- our aliases file is
/etc/mail/aliases: 1952 aliases, longest 541 bytes, 60209 bytes total

- aliases is nis map on master server and so all unix system has same user aliases.

Sachin

Re: sendmail limits .. ??

SSP_1 — Mon, 10 Dec 2001 12:06:09 GMT

Hi Sachine can I have your email id?