Re: slurpd vs ldapsync

[Howard Chu <hyc@symas.com>]

Emmanuel Dreyfus wrote:
> On Thu, Mar 22, 2007 at 02:44:19AM -0700, Howard Chu wrote:
> > Just because the protocol was defined a particular way (consumer 
> > initiated single master replication) doesn't mean it can't be used in 
> > other ways. OpenLDAP is far more flexible than that. We've enhanced the 
> > basic syncrepl functionality a number of different ways (delta-syncrepl, 
> > proxied syncrepl, mirrormode, and multimaster) all without altering any 
> > of the syncrepl protocol definition. All it takes is a little creativity 
> > to assemble the pieces in the proper order.
>
> And what are the reasons for not using slurpd? It has less functionnalities,
> but can it be considered reliable? Should I change my working setup for 
> syncrepl, or can I live with slurpd?
Problems with slurpd have been discussed on the lists and recorded in 
the ITS many times over the years. I'll just recap briefly:

No, it is not reliable. It is extremely sensitive to the ordering of 
records in the replog; it can easily go out of sync at which point 
manual intervention is required to resync the slave database with the 
master.

Syncrepl is self-synchronizing; you can start with a database in any 
state from totally empty to fully sync'd and it will automatically do 
the right thing to achieve and maintain synchronization.

Slurpd isn't very tolerant of unavailable servers. If a slave goes down 
for a long time, the replog may grow to a size that's too large for 
slurpd to process. Some of these problems are fixable, but there's 
really no point. Syncrepl covers all the bases slurpd did, plus more.

The slurpd code is going to be deleted from the source tree. Maybe not 
in 2.4 (though I think that's still possible) but certainly by 2.5.
--
  -- Howard Chu
  Chief Architect, Symas Corp.  http://www.symas.com
  Director, Highland Sun        http://highlandsun.com/hyc
  Chief Architect, OpenLDAP     http://www.openldap.org/project/