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

Re: High Availability Recommendation

From: Justin Johnson <justinjohnson_at_gmail.com>
Date: 2007-01-31 22:42:24 CET

> >>> > > I am using FSFS. I was planning on having the filesystem mounted on
> >>> > > two systems at the same time, but only so we can quickly fail over if
> >>> > > one goes down. Won't the repository be corrupted if two servers are
> >>> > > actively writing to the same repository at the same time? If not, I
> >>> > > am confused as to how.
> >>> > >
> >>> >
> >>> > It's been explained to me that the with FSFS format, the file locking with
> >> the Subversion binaries the transaction files in the FSFS directories keep
> >> things in check. But this means putting a set of Subversion binaries on
> > each
> >> server and not the NFS mount. However, the binaries don't require much
> >> configuration. As you said, hooks scripts and other stuff involving the
> >> repositories themselves is where all the configuration occurs.
> >>>
> >>> Wow, that would be great! Can someone else confirm this for me and
> >>> explain how it works or point me to something I can read about it?
> >>> Why would this work only if the binaries aren't on the NFS mount? I
> >>> can see the need for different configuration files in Apache due to
> >>> different host names for the servers. Is there some other reason the
> >>> binaries would need to be off of the NFS mount?
> >>
> >> In addition to needing confirmation about whether multiple servers can
> >> write to a repository on the same disk NFS mounted on all of the
> >> servers, I am also concerned about NFS in general. The notes at
> >> http://svn.collab.net/repos/svn/trunk/notes/fsfs in the "Locking"
> >> section indicate that there might be some issues with NFS. Can anyone
> >> confirm or deny this? Are any issues with with FSFS repositories and
> >> NFS/NAS, any special NFS mount options, performance issues, etc.
> >>
> >> Thanks,
> >> Justin
> >
> > Yeah, I had mentioned that as well one time back in a posting here, I was
> > quickly told that wasn't the case any more and that the book needs to be
> > updated there because of FSFS.
> >
> > Johnathan
>
> Here's an earlier thread that dealt with clustering of Subversion. In particular check the responses from Ryan Schmidt and Garrett Rooney. Hope this helps,
>
> http://subversion.tigris.org/servlets/BrowseList?list=users&by=thread&from=518292
>

Thanks for your research Johnathan.

Is there anyone on this list who can confirm that multiple servers
with the same disk mounted (NFS/NAS or SAN) can be load balanced where
they potentially simultaneously write to the same repository without
corrupting it? This would be wonderful, but I'm not comfortable doing
so without someone on the Subversion project saying it would work.
Some clarification on Garrett Rooney's comments on that thread about
dav related files or Tom Mornini's use of AoE/GFS would be helpful as
well. Maybe I'll have to reply to that post to get more information.

Thanks,
Justin

---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@subversion.tigris.org
For additional commands, e-mail: users-help@subversion.tigris.org
Received on Wed Jan 31 22:43:07 2007

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