Re: Monitoring IMAP thread count

[Steve Hillman <hillman@sfu.ca>]

While you can query the Zimbra Admin REST API and get what it *thinks* are the number of connections, this, in our experience, tends to be wrong. We've been graphing that number for some time and never saw it get near the limit, yet at the start of this semester, we started getting IMAP problems too.  Sure enough, when we poked around, we found we were typically 100-200 connections higher than what was being reported.

I think the simplest check is this, on each mailbox server: "netstat -an | grep <IMAPPORT#> | grep ESTABLISHED | wc -l" (that's assuming you have nginx in front and your IMAP port # on the mailbox servers is a high port, like 7143. If it's port 143, you'll get false matches)

The connections reported by zmstat-chart are also accurate, but they're not typically designed to be fetched real-time

----- "mem@isc.upenn.edu via zimbra-hied-admins-request" <mem@isc.upenn.edu> wrote:

> Hi folks,
> 
> Lately we've been running into trouble with our IMAP thread counts 
> reaching our defined limits, which seemed to be high enough until very
> 
> recently. We'd like to monitor the thread counts and have an alert
> when 
> we are getting close to our limit.
> 
> Does anyone have any experience with this? and if so, what are you
> doing 
> to monitor thread counts?
> 
> Thanks,
> -- 
> Matt Miller
> ISC/Network Services          phone:  215-573-3829
> University of Pennsylvania   jabber: mem@upenn.edu
>                         ----
> DA49 9257 E1B9 4C6F C94B  7E3C A2A4 32E3 55F8 E421

-- 
Steve Hillman                                IT Architect
hillman@sfu.ca                               IT Infrastructure
778-782-3960                                 Simon Fraser University