Scott Adkins wrote:
cannot connect to saslauthd server: Connection refused
Failed to connect to socket /var/cyrus/imap/socket/lmtp for
local_cyrus_deliver
transport: Connection refused
error sending to idled: 0
The first thing I would do here is to use LMTP as a TCP socket instead of
a UNIX domain socket. We use Tru64 in our environment, and when I first
deployed Cyrus under that architecture, the first thing I noticed what
that
as load increased, the more "connection refused" messages I saw with
LMTP.
Pointing my MTA to a TCP LMTP socket completely eliminated that
problem for
us. However, you should still keep the UNIX socket, since the "deliver"
program still uses that instead of the TCP socket (the last time I
checked).
Additionally, when setting up the TCP socket, it would be good to set
it to
listen only on localhost or a private address (to prevent Internet users
from connecting to your LMTP server and bypassing your MTA and spam/virus
filtering controls). It is either that, or you configure authentication
for the LMTP server (which, admittedly, I have never done).
For SASL, I don't know if there can be any changes there. We use UNIX
sockets for it as well, and I haven't investigated to see if there is a
TCP socket option. That might help if there is one. On our system, when
I see load increase, I definitely see SASL authentication take longer as
well. We have worked most of our load problems out (Tru64 related), so
that has improved considerably. We use the "poll" method, not "idled".
Good luck.
Thanks for those suggestions.
We managed to mitigate the SASL problem by running it as a real-time
process, which at least allowed people to log in; it's also been
suggested that, since we're on Solaris, rebuilding it to use RPC doors
instead might help. And I suppose we might be able to work around the
other symptoms as well - but the stress placed on the system is so
disproportionate to the advantage gained from idled that the obvious
thing to do (which we've done) is to switch back to the poll method; we
don't see any socket errors at all with idled disabled, and the system
load is trivial.
regards,
Adam.
--
--------------------------------
Adam Stephens
Network Specialist - Email & DNS
adam.stephens@xxxxxxxxxxxxx
----
Cyrus Home Page: http://cyrusimap.web.cmu.edu/
Cyrus Wiki/FAQ: http://cyrusimap.web.cmu.edu/twiki
List Archives/Info: http://asg.web.cmu.edu/cyrus/mailing-list.html
