[Dovecot] Problem about dovecot Panic

[FABIO FERRARI]

Good morning,
we have 2 Redhat Enterprise 5.7 machines, they are a cluster with some
mail services in it (postfix and dovecot 2).

The version of dovecot is dovecot-2.0.1-1_118.el5 (installed via rpm).

>From last week we have this dovecot problem: suddenly dovecot doesn't
accept any new connections, the dovecot.log file reports lines like these

Mar 15 12:38:54 secchia dovecot: imap: Panic: epoll_ctl(add, 5) failed:
Invalid argument
Mar 15 12:38:54 secchia dovecot: imap: Error: Raw backtrace:
/usr/lib64/dovecot/libdovecot.so.0 [0x36ea436de0] ->
/usr/lib64/dovecot/libdovecot.so.0 [0x36ea436e3a] -> /usr/lib64/dovecot/
libdovecot.so.0 [0x36ea4362e8] ->
/usr/lib64/dovecot/libdovecot.so.0(io_loop_handle_add+0x118)
[0x36ea441498] -> /usr/lib64/dovecot/libdovecot.so.0(io_add+0x8f)
[0x36ea440b7f] -> /usr/li
b64/dovecot/libdovecot.so.0(master_service_init_finish+0x1c6)
[0x36ea430c16] -> dovecot/imap(main+0x10a) [0x41773a] ->
/lib64/libc.so.6(__libc_start_main+0xf4) [0x36ea01d994] -> dovecot/
imap [0x408179]
Mar 15 12:38:54 secchia dovecot: master: Error: service(imap): child 14514
killed with signal 6 (core dumps disabled)
Mar 15 12:38:54 secchia dovecot: master: Error: service(imap): command
startup failed, throttling
Mar 15 12:39:50 secchia dovecot: imap-login: Error: master(imap): Auth
request timed out (received 0/12 bytes)
Mar 15 12:39:51 secchia dovecot: imap-login: Error: master(imap): Auth
request timed out (received 0/12 bytes)
Mar 15 12:39:51 secchia dovecot: imap-login: Error: master(imap): Auth
request timed out (received 0/12 bytes)
Mar 15 12:39:52 secchia dovecot: imap-login: Error: net_connect_unix(imap)
failed: Resource temporarily unavailable
Mar 15 12:39:52 secchia dovecot: imap-login: Error: net_connect_unix(imap)
failed: Resource temporarily unavailable
Mar 15 12:39:52 secchia dovecot: imap-login: Error: master(imap): Auth
request timed out (received 0/12 bytes)
Mar 15 12:39:53 secchia dovecot: imap-login: Error: net_connect_unix(imap)
failed: Resource temporarily unavailable
Mar 15 12:39:53 secchia dovecot: imap-login: Error: net_connect_unix(imap)
failed: Resource temporarily unavailable
Mar 15 12:39:54 secchia dovecot: imap-login: Error: net_connect_unix(imap)
failed: Resource temporarily unavailable
Mar 15 12:39:54 secchia dovecot: imap: Error: Login client disconnected
too early
Mar 15 12:39:54 secchia dovecot: imap: Error: Login client disconnected
too early
Mar 15 12:39:54 secchia dovecot: imap: Error: Login client disconnected
too early
Mar 15 12:39:54 secchia dovecot: imap: Error: Login client disconnected
too early
Mar 15 12:39:55 secchia dovecot: imap: Panic: epoll_ctl(add, 5) failed:
Invalid argument

and the kern.log file reports

Mar 15 12:38:52 secchia kernel: dlm: closing connection to node 1
Mar 15 12:39:04 secchia kernel: lpfc 0000:83:00.0: 1:(0):2753 PLOGI
failure DID:010400 Status:x9/x32900
Mar 15 12:39:04 secchia kernel: lpfc 0000:03:00.0: 0:(0):2753 PLOGI
failure DID:010400 Status:x9/x32900
Mar 15 12:41:14 secchia kernel: lpfc 0000:03:00.0: 0:(0):2753 PLOGI
failure DID:010400 Status:x9/x32900
Mar 15 12:41:15 secchia kernel: lpfc 0000:83:00.0: 1:(0):2753 PLOGI
failure DID:010400 Status:x9/x32900
Mar 15 12:42:11 secchia kernel: dlm: got connection from 1

can you help us?

thanks in advance

Fabio Ferrari