Thanks for those clarifications, Laszlo... and here's a few more: Yes, GFS "comes with" CS, because RH built that dependency on those two layered software products; I was merely pointing out that the question only mentioned CS, not GFS nor any other shared and/or replicated storage being used in conjunction with CS. So the fencing comment was appropriate for GFS, but it made me wonder why the stretch?
I did state the same physical LAN requirement; my point was that having a physical LAN for a _remote_ datacenter was _less likely_. So we all agree on the same thing: Red Hat Clustering works on the same physical LAN, whether that physical LAN stretches a 100 inches or a 100 miles. I think Ana should reveal more about her implementation rather than hearing about yours. ;) And what part of what I said is "false"? I didn't say anything that fail-over AND load-balancing were required. Fail-over can be achieved in numerous ways and without RH supplied tools; the load-balancing is native to Linux using IPVS. But back to the original question: will Red Hat support ... ? If you use your OWN fail-over strategy, you OWN it. Yes, OpenAIS (and likewise the former pulse on RHEL4, sorry for dating myself) is for fail-over which (either) can operate on different LANs. And to my knowledge and not practical use, the load-balancing (IPVS) can work on different LANs -- if the tunneling option is used. But my point was that I have not seen any implementation that also maintains IPVS client-session tracking on DIFFERENT LANs (which is NOT a problem if it is on the same physical LAN, like your setup). It is that last point that has obvious implications on the scope and objectives for those seeking a "supportable" Linux-based solution. Have a great day! -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Laszlo Beres Sent: Thursday, August 12, 2010 1:35 PM To: linux clustering Subject: Re: [Linux-cluster] RHCS separate datacenter On Thu, Aug 12, 2010 at 7:19 PM, <[email protected]> wrote: > FWIIW, I thought the question was in regards to Cluster Suite (RHCS), not > Global File System (GFS)? In that regard, what does fencing have to do with > this? Most cluster solutions come with shared/cluster filesystems. > @Ana, are you concerned about pulse heartbeat? That should not be an > issue, but more so, there will (probably) be no kernel client-session > tracking for fail-over, because your remote datacenter is not on the > same physical LAN. That means if you did fail- Not necessarily true, our network department was able to set up the same physical LAN in two data centers within the same town. > Also, from my understanding of Linux IPVS on which RHCS is based, is that it > can support a remote datacenter, without spanning tree, if you use the > tunneling option (not direct or nat)... although we have never tried it. False, Red Hat Cluster Suite has two different parts: failover and load balancing frameworks. The former is based on OpenAIS, while latter is IPVS with some additional components. One can operate without the other. -- László Béres Unix system engineer http://www.google.com/profiles/beres.laszlo -- Linux-cluster mailing list [email protected] https://www.redhat.com/mailman/listinfo/linux-cluster -- Linux-cluster mailing list [email protected] https://www.redhat.com/mailman/listinfo/linux-cluster
