[Dovecot] Error: Couldn't open INBOX: Timeout while waiting for lock

[Timo Sirainen]

On 21.8.2012, at 8.42, Kavish Karkera wrote:

> My users are frequetly getting the below error,
> 
> Aug 21 00:04:18 blade6 dovecot: pop3-login: proxy(hgl_dipak): Login failed to 192.168.1.43:110: [IN-USE] Couldn't open INBOX: Timeout while waiting for lock.
> 
> We are proxing pop connections from one pop server (dovecot version 1.1.20) i.e 192.168.1.39 to the other pop Server (Dovecot version 2.0.16 ) i.e 192.168.1.4.
> 
> We have set  pop3_lock_session = yes and dont want to disable it.

Are your users behind bad internet connections that leave dead connections lying around? If so, maybe changing the kernel's TCP keepalive value to something very aggressive (e.g. 10 secs) would fix those. Of course that makes other traffic behave worse.