lmtp problem - end of file reached

[Ian Eiloart]

Hi,

I have a set of cyrus servers, and a cluster of smtp servers with perdition 
IMAP proxy servers sitting in front.

I'm creating a new front end, which will replace the perdition proxies with 
a cyrus murder, so that we can share mailboxes across servers.

I'd like to include cyrus lmtpproxyd, so that my smtp servers can take 
advantage of the murder, instead of having to work out which back end to 
deliver to. Currently, they're using an LDAP server to discover the correct 
backend server. Instead, I want to deliver locally, via a UNIX domain 
socket.

The problem is that I can't get my front end to connect with lmtp through 
murder.

The problem isn't connectivity, since I can use lmtptest to connect 
directly to the backend, and actually deliver a message. And, I can 
actually get a log from the server.

However, when I deliver to the local lmtp proxy, it does this:

    snow-170 % nc -vU /opt/local/etc/cyrus/socket/lmtpproxy
    220 snow.uscs.susx.ac.uk LMTP Cyrus v2.3.8 ready
    mail from:<>
    250 2.1.0 ok
    rcpt to:<ianasdflkjds at sussex.ac.uk>
    550-Mailbox unknown.  Either there is no mailbox associated with this
    550-name or you do not have authorization to see it.
    550 5.1.1 User unknown
    rcpt to:<iane at sussex.ac.uk>
    250 2.1.5 ok
    data
    354 go ahead
    Subject: foo

    .
    451 4.4.3 Remote server unavailable

Failure to handle an unknown recipient indicates that the mailbox has been 
found through the murder. And, the "server unavailable" message is false, 
because the server has actually logged part of the proxy to server 
conversation, thus:

    >1211466931>220 mailstore1.uscs.susx.ac.uk LMTP Cyrus v2.3.8 ready
    <1211466931<LHLO murder
    >1211466931>250-mailstore1.uscs.susx.ac.uk
    250-8BITMIME
    250-ENHANCEDSTATUSCODES
    250-PIPELINING
    250-SIZE 52428800
    250-AUTH EXTERNAL
    250 IGNOREQUOTA
    >1211466931>421 4.4.1 bye end of file reached

What's more, I've seen that same conversation with tcpdump on both the 
proxy and the server hosts.

Am I right in thinking that this happened because the lmtp proxy gave up? 
Or, has the server encountered some local end of file?


LMTPTEST tells me a little more:

    snow-241 % lmtptest mailstore1.uscs.sussex.ac.uk lmtp
    S: 220 mailstore1.uscs.susx.ac.uk LMTP Cyrus v2.3.8 ready
    C: LHLO example.com
    S: 250-mailstore1.uscs.susx.ac.uk
    S: 250-8BITMIME
    S: 250-ENHANCEDSTATUSCODES
    S: 250-PIPELINING
    S: 250-SIZE 52428800
    S: 250-AUTH EXTERNAL
    S: 250 IGNOREQUOTA
    Authentication failed. no mechanism available
    Security strength factor: 0

Here, I'm beginning to suspect that the client is giving up because it 
can't authenticate. The  server is started using "-a" which means that 
we're pre-authenticated. I suspect that disabling pre-authentication might 
fix my problem, but will prevent the existing smtp/lmtp cluster from 
delivering email! In this case, I can press ahead and actually deliver the 
email.

    lhlo iane
    250-mailstore1.uscs.susx.ac.uk
    250-8BITMIME
    250-ENHANCEDSTATUSCODES
    250-PIPELINING
    250-SIZE 52428800
    250-AUTH EXTERNAL
    250 IGNOREQUOTA
    mail from:<>
    250 2.1.0 ok
    rcpt to:<iane at sussex.ac.uk>
    250 2.1.5 ok
    data
    354 go ahead
    Subject: foobar

    .
    250 2.1.5 Ok
    quit
    221 2.0.0 bye
    Connection closed.


-- 
Ian Eiloart
IT Services, University of Sussex
x3148