On 17.5.2012, at 18.22, Root Kev wrote: > We have put Dovecot 2.1.4 on several of our production servers (CentOS, on > Dell R710, with 20GB memory, dual CPU Quad-core). We have a single instance > of Dovecot running and currently have several instances of Popa3d. When > there are significant amount of popping from 2 mailboxes that dovecot that > is popping from (500+ msgs in the mailboxes), the popping of the messages > causes the boxes to become unresponsive. We use another application that > connects to the Dovecot, downloads 2-10 messages, then processes them, then > sends the delete command to Dovecot.
Unresponsive for a long time?.. What CentOS version? > When this issue occurs we are unable to become Root, or login again if we > close our ssh connection. This only occures when Dovecot is doing the > popping. If we only run the older Popa3d, this doesn't occur. We believe > it is caused by the way dovecot is authenticating. Sounds like PAM is hanging. Is the (CPU) load in general high at this time? > We are using auth_mechanisms = plain > > passdb > drive = shadow > > usedb > driver = passwd > args = blocking=yes Using shadow/passwd directly shouldn't affect PAM at all. So this is a rather strange problem..