[2.3.11] sync_client bug: Starting MASTER imap-server can be delayed for 1000s if SLAVE is down.

[Bron Gondwana]

On Mon, Jan 14, 2008 at 11:18:22PM +0300, Boris Lytochkin wrote:
> How to replicate:
> 1) Set replication up (master's cyrus.conf runs sync_client w/o -o option)
> 2) Shutdown both master & slave
> 3) Start MASTER cyrus.
> 
> While SLAVE is down MASTER do not start services (i.e. imap server is
> down for users) because sync_client do not go into background.
> 
> There is a patch in attachment that:
> - fixes this bug releasing MASTER as soon as possible (even before connecting to SLAVE)
> - adds some additional debug messages into do_sync(...)
> - adds -D flag that disables 1st-level fork() for sync_client.

There's also the "-o" flag (I see I didn't add it in the synopsis
at the top of the manpage, oops, but it's documented in the main
option listing).  This is what we use at FastMail so master will
continue to start.

Bron.