"Nick Havard" <nick@nickhavardxyz.com> wrote in message news:<j0xUb.48332$OA3.15149801@newsfep2-win.server.ntli.net>...
> "Axel Neumann" <Axel.Neumann@epost.de> wrote in message
> news:bvu49e$vfr7i$1@ID-55633.news.uni-berlin.de...
> >
> > "Nick Havard" <nick@nickhavardxyz.com> wrote:
> > > Hi
> > >
> > > I have a small two node Sun Cluster 3 setup which is using two cross
> over
> > > cables for interconnects. I beleive the cross over cables are causing
> some
> > > issues and wish to change it to use switches/hubs that sit in the
> middle.
> > > For this I thik there are two options as below.
> > > * Use two small hubs, one for each interconnect
> > > * Use a single small switch for all interconnect cables
> > >
> > > My question is will the later option work, or will the cluster detect
> > > incorrect traffic on the interconnects (i.e. have confusion between each
> > > interconnect "channel") and give me more problems than it would solve,
> or
> > > would the switch sort itself out and isolate the network traffic on each
> > > interconnect. The second option is my preferred as it requires only a
> single
> > > power socket and one device. As this is only a play cluster I'm not too
> > > concerned about single point of failure etc.
> > >
> > > Thanks for your help.
> > >
> > > Regards
> > >
> > > Nick
> > > nick@nickhavardxyz.com
> > >
> > > P.S. Remove xyz to reply
> > >
> > Hi,
> >
> > If the cluster is covered by a support contract from Sun you have to use
> two
> > switches. A single switch solution is not supported.
> >
> > HTH,
> >
> > Axel Neumann
> >
> >
> Hi
>
> No the cluster definitely isn't under support. It's a small cluster of an
> Ultra-5 and Ultra-10 with some Multipacks for shared storage that I use for
> "working" and learning on at home. Thus I'm not bothered about having
> component reliability etc.
>
> One of the problems I seem to have is that is I take one node down etc, it
> causes problems at the other node (sometimes crashing it), which I beleive
> is due to the loss of a cluster interconnect at the interface. Therefore by
> using a switch or hub I would eliminate this as the node that remains, the
> interconnect interface would still beleive it was connected to a network.
>
> If I could use a single switch for all four interconnect interfaces, it
> would suit me as IO have far to many power sockets in use already. However
> I'm not sure if a switch would isolate the interconnect traffic between the
> two interconnect channels in a satisfacory manner, or would the cluster
> detect inappropriate traffic on each interconnect (as it would with a single
> hub) and have additional problems.
>
> Regards
>
> Nick
> nick@nickhavardxyz.com
>
> P.S. Remove xyz to reply

Even if you were to lose the interconnect, you shouldn't lose the
cluster when one node is powered off/suddenly fails. If your quorum
is properly functioning the surviving node should place a reservation
and take ownership of the cluster crashing any other nodes that don't
have access to the interconnect. Perhaps post an scstat from your
cluster when it is operating?