Mailman + Postfix - Too Many Connections
This is not strictly a mailman issue, but I would assume some people here would have encountered this issue.
We sent out mailing lists to schools here in Australia, and recently we've been getting "Too Many Connections #421" errors from them. Mails destined to gmail or hotmail are OK.
We're not trying to spam them (we have put links to unsubscribe, etc) but since the same mail server hosts emails for almost all the school domains, it's not liking us. I've set postfix variable of default_destination_recipient_limit to 15, still not liking it.
Any suggestions on rate-limiting on Postfix / mailman??
Please consider the environment before you print
On Thu, 07 May 2009 15:42:45 +1000 "Lie, Jafaruddin" lie@acer.edu.au wrote:
This is not strictly a mailman issue, but I would assume some people here would have encountered this issue.
We sent out mailing lists to schools here in Australia, and recently we've been getting "Too Many Connections #421" errors from them. Mails destined to gmail or hotmail are OK.
We're not trying to spam them (we have put links to unsubscribe, etc) but since the same mail server hosts emails for almost all the school domains, it's not liking us. I've set postfix variable of default_destination_recipient_limit to 15, still not liking it.
Any suggestions on rate-limiting on Postfix / mailman??
It's horrible trying to debug things like this, working out what their limit is and then sticking to it. Try asking them what limits they are imposing (or search Google to see if anybody else has researched it) and then set them.
It isn't Mailman you want to be looking at, it is Postfix. I'm not a Postfix expert but http://www.postfix.org/postconf.5.html has lots of settings you could be looking at such as default_destination_concurrency_limit, default_destination_recipient_limit, default_recipient_limit.
See also http://dev.riseup.net/grimoire/mail/postfix/dedicated-transport/ if you want to be limiting for just a handful of destinations.
-- Alice
Alice Kaerast wrote:
On Thu, 07 May 2009 15:42:45 +1000 "Lie, Jafaruddin" lie@acer.edu.au wrote:
This is not strictly a mailman issue, but I would assume some people here would have encountered this issue.
We sent out mailing lists to schools here in Australia, and recently we've been getting "Too Many Connections #421" errors from them. Mails destined to gmail or hotmail are OK.
We're not trying to spam them (we have put links to unsubscribe, etc) but since the same mail server hosts emails for almost all the school domains, it's not liking us. I've set postfix variable of default_destination_recipient_limit to 15, still not liking it.
Any suggestions on rate-limiting on Postfix / mailman??
Try working around this when your upstream gives 550 errors for rate limiting :p.
Anyway, the way to do concurrency limiting on exim (just so we have it in the archives) is to add serialize=* in your transport. rate limiting isn't that easy and waiting for the 4xx error is probably the easiest, just set your retry rules to retry every 15 minutes continually.
Either way, Too Many Connections sounds like concurrency to me, not rate limiting.
Jaco
- "Lie, Jafaruddin" lie@acer.edu.au wrote:
We sent out mailing lists to schools here in Australia, and recently we've been getting "Too Many Connections #421" errors from them. Mails destined to gmail or hotmail are OK.
Not really a mailman problem, have a look at:
http://www.postfix.org/QSHAPE_README.html#backlog
Ciao Stefan
Stefan Förster http://www.incertum.net/ Public Key: 0xBBE2A9E9 Eher hält der Mensch das Feuer im Munde als ein Geheimnis.
- Petronius
participants (4)
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Alice Kaerast -
Jaco Kroon -
Lie, Jafaruddin -
Stefan Förster