[svn.haxx.se] · SVN Dev · SVN Users · SVN Org · TSVN Dev · TSVN Users · Subclipse Dev · Subclipse Users · this month's index

Re: Subversion Mirroring

From: WANdisco <elaine.murphy_at_wandisco.com>
Date: 2007-10-05 05:31:16 CEST

The key problem with using svnsync for multiple Subversion repositories
distributed over a WAN is its reliance on a master-slave architecture. While
svnsync does provide the advantage of having local read-only repositories at
each of the remote development sites, only the master repository is
writeable. The master repository is then replicated to the read only slaves.
However, replication can place a significant load on the network and
servers. In addition, best practice requires the master server to be
unavailable for write operations while replication is taking place, in order
to avoid file corruption and other inconsistencies. For these reasons,
replication tends to happen on an infrequent basis, leaving the read-only
slave repositories that remote sites do their checkouts from out of sync
with the master much of the time. As a result, commit failures due to update
conflicts on the master repository can become a problem. In order to avoid
commit failures, developers at the slave repository sites have to do updates
over the WAN against the master Subversion repository before doing their
commits. This can negate most of the expected network performance and
developer productivity benefits of using svnsync in a distributed
development environment.

Other solutions such as svk do allow multiple repositories to be readable as
well as writeable, but there are no guarantees of consistency across the
repositories. A commit can succeed on a developer’s local repository where
there are no conflicts, and fail when it’s copied to other sites’
repositories due to update conflicts. This can make administration extremely
difficult.

WANdisco solves these problems by turning distributed Subversion
repositories into peers. All of the repositories are writeable, and
consistency across the repositories is guaranteed. WANdisco’s active-active
replication capabilities allow developers to work at LAN speed over the WAN
for both read and write operations, while keeping all of the repositories in
sync, in effect in real-time. WANdisco also provides self-healing
capabilities that automate disaster recovery after a network outage or
server failure.

Res Pons wrote:
>
> Thank you for the link :)
>
> ----Original Message Follows----
> From: "Andy Levy" <andy.levy@gmail.com>
> To: "Res Pons" <pons32@hotmail.com>
> CC: users@subversion.tigris.org
> Subject: Re: Subversion Mirroring
> Date: Wed, 12 Apr 2006 13:33:53 -0400
> MIME-Version: 1.0
> Received: from pproxy.gmail.com ([64.233.166.180]) by
> bay0-mc4-f9.bay0.hotmail.com with Microsoft SMTPSVC(6.0.3790.1830); Wed,
> 12
> Apr 2006 10:33:54 -0700
> Received: by pproxy.gmail.com with SMTP id c63so1588023pyc for
> <pons32@hotmail.com>; Wed, 12 Apr 2006 10:33:53 -0700 (PDT)
> Received: by 10.35.15.11 with SMTP id s11mr488683pyi; Wed, 12 Apr
> 2006 10:33:53 -0700 (PDT)
> Received: by 10.35.70.10 with HTTP; Wed, 12 Apr 2006 10:33:53 -0700 (PDT)
> X-Message-Info: JGTYoYF78jEHjJx36Oi8+Z3TmmkSEdPtfpLB7P/ybN8=
> DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta;
> d=gmail.com;
>
> h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references;
>
> b=HMXPherLwn30sEv1ny1B9al3gwyTrlCG8fMAsXIGZJ31t1Sip4Kr7xZZnXixtQGv4HZAyXelDWC4vbi5jXv0UBaP12twqDOy0a52+PZQ2LesciKQ5p/R/6XTjeQkcYqQMtjrjYWdxYpn1m1uClDqCoa2i9PsAgasns70JkNjWjc=
> References: <BAY113-F256ADBA80BA8461AE91DECCC20@phx.gbl>
> Return-Path: andy.levy@gmail.com
> X-OriginalArrivalTime: 12 Apr 2006 17:33:55.0408 (UTC)
> FILETIME=[45DF8500:01C65E57]
>
> On 4/12/06, Res Pons <pons32@hotmail.com> wrote:
> > Hi Forum
> >
> > Could someone please tell me how I go about mirroring SVN? Our
> > international offices are very slow to login to our US repo server.
> I'm
> not
> > sure how to go about this? Any ideas?
>
> http://svk.elixus.org/
>
> _________________________________________________________________
> Is your PC infected? Get a FREE online computer virus scan from McAfee®
> Security. http://clinic.mcafee.com/clinic/ibuy/campaign.asp?cid=3963
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@subversion.tigris.org
> For additional commands, e-mail: users-help@subversion.tigris.org
>
>
>

-- 
View this message in context: http://www.nabble.com/Subversion-Mirroring-tf1439416.html#a13052969
Sent from the Subversion Users mailing list archive at Nabble.com.
---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@subversion.tigris.org
For additional commands, e-mail: users-help@subversion.tigris.org
Received on Fri Oct 5 05:31:32 2007

This is an archived mail posted to the Subversion Users mailing list.

This site is subject to the Apache Privacy Policy and the Apache Public Forum Archive Policy.