Cyrus IMAP server

Bron Gondwana brong at
Thu Oct 21 17:46:41 EDT 2010

Actually in Cyrus 2.4 you will find that it allows multiple concurrent pop connections. Each one gets a "snapshot" of the mailbox at the time it connects. All operations are to this snapshot.

This is safe because the namelocking semantics ensure the message files won't be deleted until all open connections are closed, and the snapshot includes uids to let the pop3d find and delete the correct messages.

So you'll be good in 2.4 :)


"Jeroen van Meeuwen (Kolab Systems)" <vanmeeuwen at> wrote:

>Dan White wrote:
>> On 21/10/10 16:43 +0200, JC Putter wrote:
>> >we are running cyrus-imapd 2.3 on centos 5.5
>> >
>> >we are getting complains from users getting error messages saying Mailbox
>> >locked by POP Server, i understand that pop3 server can handle only 1
>> >concurrent connection, can cyrus be configured to support more connection?
>> We're getting a lot more of these complaints as well as our ISP customers
>> start configuring email access on their phones and handhelds.
>> The solution for us has been to encourage customers to reconfigure both
>> devices (PC and phone) to use IMAP.
>> The POP3 standard (RFC 1939) requires each connection to obtain an
>> exclusive lock on a maildrop before continuing operations. It lacks the
>> proper semantics to handle simultaneous access to a mailbox.
>Hi there,
>I went ahead and put this protocol limitation in my work-in-progress 
>Deployment Guide document ;-)
>Kind regards,
>Jeroen van Meeuwen
>Senior Engineer, Kolab Systems AG
>e: vanmeeuwen at
>t: +316 42 801 403
>pgp: 9342 BF08
>Cyrus Home Page:
>List Archives/Info:

Sent from my Android phone with K-9 Mail. Please excuse my brevity.

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