Sync_client fails after upgrade 2.3.16 to 2.4.4

[Chris Conn]

>> Hmm I hadn't read that. I was aware that doing it in a high volume
>> scenario was problematic, but was under the impression that an
>> occasional delivery here and there was theoretically possible. Its
>> pretty amazing since I test it manually and I can send to either one or
>> the other and replication happens correctly; however, when the stupid
>> logrotate message gets sent on the slave within seconds of a similar
>> message being sent on the master, things die.
>
> Must be a timing issue that sync_client can't handle.
>

Clearly.  A cronjob I made to echo to the stdout every minute on both 
the master and the slave causes instant death to replication.  I don't 
have to wait until tomorrow morning to find out.

I am going to find a way to pipe locally generated mail to a process 
that smarthosts/mailhubs to the master.   Hopefully someday cyrus will 
be able to handle inbound emails on replicated systems, as well as 
pop3/imap traffic.  The world would be ideal :)

C.