Hello Emmanuel, My idea is deferent, a coponent is available and can give me some possibility. I don't need this features, why should I add something which can grow problems ;) ? In my case, problem was also that my storage acces was unstable, so qdisk was very annoying. Regards -- .`'`. GouNiNi : ': : `. ` .` GNU/Linux `'` http://www.geekarea.fr ----- Mail original ----- > De: "emmanuel segura" <emi2fast@xxxxxxxxx> > À: "linux clustering" <linux-cluster@xxxxxxxxxx> > Envoyé: Mercredi 25 Avril 2012 18:05:09 > Objet: Re: Redhat without qdisk > > > > Hello GouNiNi > > I use cluster with qdisk && master_wins=1 and without heuristic > parameter and i can tell you, i never found a problem > > I have a normal quetion, if i have a component problem in a cluster. > What can i do? > > 1:Remove the component > 2:Look for a solution > > Sorry but i prefer the sencod choice :-) > > > > Il giorno 25 aprile 2012 15:48, GouNiNi < gounini.geekarea@xxxxxxxxx > > ha scritto: > > > Hello, > > I manage many cluster and I had lot of problem as long as I used > quorum device. > Until I remove this, my cluster are stable. I agree whith Lon > Hohberger and Ryan O'Hara point of view. > > You have to ask you : Do I need specific check (heuristic) or do I > need scenario like "all but one" ? > If your answer are "no", please don't use quorum device. > > The only problem you have to correct will be when network > communication split two nodes. Both think to have quorum and try to > fence the other (split brain situation). To prevent this, last > clusterv2 provides redondance ring (not officially supported on > RHEL5) and RHEL6 have similare feature I think. > > Regards, > > -- > .`'`. GouNiNi > : ': : > `. ` .` GNU/Linux > `'` http://www.geekarea.fr > > > ----- Mail original ----- > > De: "Gunther Schlegel" < schlegel@xxxxxxxxx > > > À: linux-cluster@xxxxxxxxxx > > Envoyé: Lundi 16 Avril 2012 17:15:52 > > Objet: Re: Redhat without qdisk > > > > > > Hi, > > > > > But if you have problem with your storage it's normale the node > > > goes > > > fenced, because your cluster services depends on storage > > > > Well, no, my clustered services do not depend on SAN storage. > > > > > Or maybe you wold like to have a cluster running without san disk > > > > I need the qdisk for two reasons: > > > > - heuristics > > - to safely achieve quorum in a two-node-cluster if only one node > > is > > up. > > > > regards, Gunther > > > > > Il giorno 13 aprile 2012 11:20, Gunther Schlegel > > > < schlegel@xxxxxxxxx > > > <mailto: schlegel@xxxxxxxxx >> ha scritto: > > > > > > Hi Lon, > > > > > > > > Why redhat made the qdisk as Tie-breakers and some people > > > > > from > > > support > > > > > say it's one optional or some time says is not needed? > > > > > > > > It is optional and is often not needed. It was developed > > > > really > > > for two purposes: > > > > > > > > - to help resolve fencing races (which can be resolved using > > > delays or other tactics) > > > > > > > > - to allow 'last-man-standing' in >2-node clusters. > > > > > > > > With qdiskd you can go from 4 to 1 node (given properly > > > > configured > > > heuristics). The other 3 nodes then, because heuristics fail, > > > can't > > > "gang up" (by forming a quorum) on the surviving node and take > > > over > > > - this means your critical service stays running and available. > > > The > > > problem is that, in practice, the "last node" is rarely able to > > > handle the workload. > > > > > > > > This behavior is obviated by features in corosync 2.0, which > > > > gives > > > administrators the ability to state that a -new- quorum can > > > only > > > form if all members are present (but joining an existing quorum > > > is > > > always allowed). > > > > > > > > > Is this in RHEL6? I am still trying to solve the following > > > situation: > > > > > > - 2 node cluster without need for shared storage (no gfs) > > > - qdiskd in place because of the heuristics. > > > - Cluster is fine if both nodes have network communication and > > > heuristics reach the minimum score. > > > > > > Problem: if the shared storage the qdisk resides on becomes > > > unavailable (but everything else is fine) a node will be > > > fenced. It > > > actually happens at the time the shared storage comes back > > > online, > > > the node re-establishing the storage link first wins and fences > > > the > > > other one. I try to mitigate that with loooong timeout > > > settings, but > > > therefore a necessary cluster switch eviction is also delayed. > > > > > > I would really appreciate if the qdiskd would withdraw it's > > > quorum > > > vote and not do any fencing at all. The cluster would survive > > > as > > > quorum is also gathered if the cluster network connection is > > > established. > > > > > > best regards, Gunther > > > > > > > > > Gunther Schlegel > > > Head of IT Infrastructure > > > > > > > > > -- > > > > > > > > > ............................................................. > > > Riege Software International GmbH Phone: +49 2159 91480 > > > <tel:%2B49%202159%2091480> > > > Mollsfeld 10 Fax: +49 2159 914811 > > > <tel:%2B49%202159%20914811> > > > 40670 Meerbusch Web: www.riege.com > > > < http://www.riege.com > > > > Germany E-Mail: schlegel@xxxxxxxxx > > > <mailto: schlegel@xxxxxxxxx > > > > -- -- > > > Commercial Register: Managing Directors: > > > Amtsgericht Neuss HRB-NR 4207 Christian Riege > > > VAT Reg No.: DE120585842 Gabriele Riege > > > Johannes Riege > > > Tobias Riege > > > ............................................................. > > > YOU CARE FOR FREIGHT, WE CARE FOR YOU > > > > > > > > > > > > > > > -- > > > Linux-cluster mailing list > > > Linux-cluster@xxxxxxxxxx <mailto: Linux-cluster@xxxxxxxxxx > > > > https://www.redhat.com/mailman/listinfo/linux-cluster > > > > > > > > > > > > > > > -- > > > esta es mi vida e me la vivo hasta que dios quiera > > > > > > > > > -- > > > Linux-cluster mailing list > > > Linux-cluster@xxxxxxxxxx > > > https://www.redhat.com/mailman/listinfo/linux-cluster > > > > -- > > Gunther Schlegel > > Head of IT Infrastructure > > > > > > > > > > ............................................................. > > Riege Software International GmbH Phone: +49 2159 91480 > > Mollsfeld 10 Fax: +49 2159 914811 > > 40670 Meerbusch Web: www.riege.com > > Germany E-Mail: schlegel@xxxxxxxxx > > -- -- > > Commercial Register: Managing Directors: > > Amtsgericht Neuss HRB-NR 4207 Christian Riege > > VAT Reg No.: DE120585842 Gabriele Riege > > Johannes Riege > > Tobias Riege > > ............................................................. > > YOU CARE FOR FREIGHT, WE CARE FOR YOU > > > > > > > > > > -- > > Linux-cluster mailing list > > Linux-cluster@xxxxxxxxxx > > https://www.redhat.com/mailman/listinfo/linux-cluster > > -- > Linux-cluster mailing list > Linux-cluster@xxxxxxxxxx > https://www.redhat.com/mailman/listinfo/linux-cluster > > > -- > esta es mi vida e me la vivo hasta que dios quiera > > -- > Linux-cluster mailing list > Linux-cluster@xxxxxxxxxx > https://www.redhat.com/mailman/listinfo/linux-cluster -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
