Aki-san

Last night We adjusted the "process_limit" in the stats service to get rid of the error.

"client_limit" is in the blank (default) state.

Thank you very much.

morikawa -----Original Message----- From: 'Aki Tuomi' [mailto:aki.tuomi@open-xchange.com] Sent: Tuesday, November 17, 2020 2:35 PM To: 森川　孝司 <morikawa-k6@itec.hankyu-hanshin.co.jp>; dovecot@dovecot.org Subject: RE: about imap-login: Error and imap: Error after Version-UP

You need to configure stats service client limit and imap service client limit. Those are different services than imap-login service.

Aki

On 17/11/2020 01:28 森川　孝司 <morikawa-k6@itec.hankyu-hanshin.co.jp> wrote:

Aki-san

I have already seen that page. Is the setting method wrong?

Is there any other tuning point?

morikawa -----Original Message----- From: Aki Tuomi [mailto:aki.tuomi@open-xchange.com] Sent: Monday, November 16, 2020 8:52 PM To: 森川　孝司 <morikawa-k6@itec.hankyu-hanshin.co.jp>; dovecot@dovecot.org Subject: Re: about imap-login: Error and imap: Error after Version-UP

...

On 16/11/2020 13:44 森川　孝司 <morikawa-k6@itec.hankyu-hanshin.co.jp> wrote:

We have upgraded dovecot from 2.0.9 (centos6) to 2.2.36 (centos8).

If more than 1000 users log in, the following error will occur.

Nov 16 11:33:00 xxxxxxxx dovecot[1361]: imap-login: Error: master(imap): net_connect_unix(imap) failed: Resource temporarily unavailable - http://wiki2.dovecot.org/SocketUnavailable (client-pid=1362, client-id=129834, rip=10.10.10.10, created 551 msecs ago, received 0/4 bytes) Nov 16 11:30:26 xxxxxxxx dovecot[1361]: imap: Error: net_connect_unix(/var/run/dovecot/stats-writer) failed: Resource temporarily unavailable

I set the following because I thought it was a problem with the number of connections, but I get an error.

service imap-login { service_count=0 client_limit = $default_client_limit process_min_avail = 4 process_limit = $default_process_limit vsz_limit = 1G }

limits.conf

• soft nofile 4096
• hard nofile 4096

---

cat /proc/sys/net/core/somaxconn

4096

Is there any other tuning point? Where should I look?

https://wiki.dovecot.org/SocketUnavailable

Aki