[Gluster-users] Stupid question re multiple networks

[Justin Clift]

On Thu, 13 Nov 2014 14:15:24 -0500 (EST)
Jeff Darcy <jdarcy at redhat.com> wrote:

> > AFAIK multiple network scenario only works if you are not using
> > Gluster via FUSE mounts or gfapi from remote hosts. It will work
> > for NFS access or when you set up something like Samba with CTDB.
> > Just not with native Gluster as the server always tells the clients
> > which addresses to connect to: ie your storage hosts will always
> > supply the connection details of the hosts that are configured in
> > gluster to your storage clients.
> >
> > I wonder if this could be gaffer-taped with some bridging/vlan/arp
> > spoofing trickery but I'm not sure I'd trust such a hack.
> >
> > It would be *really* nice if there was a way to set up gluster so
> > you could specify different IPs for backend and frontend operations.
> 
> As you suggest, there are various kinds of "trickery" that can be used
> to fake multi-network support even for native mounts.  I've seen it
> done via split-horizon DNS, explicit host routes, and iptables.
> *Proper* support for multiple networks is part of the proposed 4.0
> feature set.
> 
> http://www.gluster.org/community/documentation/index.php/Planning40
> 
> In fact, I would greatly appreciate your help defining what "proper"
> means in this context.

As an extra data point, this is a gluster-devel thread from a while ago
about one potential approach:

  https://lists.gnu.org/archive/html/gluster-devel/2013-06/msg00069.html

It turned out the code (at the time) in GlusterFS for identifying
peers wasn't great, and needed to be updated first before really
addressing the problem at all. ;)

  https://lists.gnu.org/archive/html/gluster-devel/2013-06/msg00067.html

Those two threads should be read together, as the concept in the first
one evolved during discussion with Kaushal M (CC'd) and via the mailing
list and IRC over a few days.

This pre-requisite required code became the "Better Peer Identification"
feature for 3.6.x series:

  http://www.gluster.org/community/documentation/index.php/Features/Better_peer_identification

I haven't kept an eye on that though, so unsure if it's completed yet
or not (just now emailed Kaushal to find out).

+ Justin

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