>>> Antony Stone <antony.st...@ha.open.source.it> schrieb am 04.08.2021 um 21:27 in Nachricht <202108042127.43916.antony.st...@ha.open.source.it>: > On Wednesday 04 August 2021 at 20:57:49, Strahil Nikolov wrote: > >> That's why you need a qdisk at a 3‑rd location, so you will have 7 votes in >> total.When 3 nodes in cityA die, all resources will be started on the >> remaining 3 nodes. > > I think I have not explained this properly. > > I have three nodes in city A which run resources which have to run in city > A. > They are based on IP addresses which are only valid on the network in city > A. > > I have three nodes in city B which run resources which have to run in city > B. > They are based on IP addresses which are only valid on the network in city > B. > > I have redundant routing between my upstream provider, and cities A and B, > so > that I only _need_ resources to be running in one of the two cities for > everything to work as required. City A can go completely offline and not > run > its resources, and everything I need continues to work via city B. > > I now have an additional requirement to run a single resource at either city
> A > or city B but not both. > > As soon as I connect the clusters at city A and city B, and apply the > location > contraints and weighting rules you have suggested: > > 1. everything works, including the single resource at either city A or city > B, > so long as both clusters are operational. > > 2. as soon as one cluster fails (all three of its nodes nodes become > unavailable), then the other cluster stops running all its resources as > well. > This is even with quorum=2. Have you ever tried to find out why this happens? (Talking about logs) > > This means I have lost the redundancy between my two clusters, which is > based > on the expectation that only one cluster will fail at a time. If the > failure > of one automatically _causes_ the failure of the other, I have no high > availability any more. > > What I require is for cluster A to continue running its own resources, plus > the single resource which can run anywhere, in the event that cluster B > fails. > > In other words, I need the exact same outcome as I have at present if > cluster > B fails (its resources stop, cluster A is unaffected), except that cluster A > > continues to run the single resource which I need just a single instance of. > > It is impossible for the nodes at city A to run the resources which should > be > running at city B, partly because some of them are identical ("Asterisk" as > a > resource, for example, is already running at city A), and partly because > some > of them are bound to the networking arrangements (I cannot set a floating IP > > address which belongs in city A on a machine which exists in city B ‑ it just > > doesn't work). > > Therefore if adding a seventh node at a third location would try to start > _all_ resources in city A if city B goes down, it is not a working solution. > > If city B goes down then I simply do not want its resources to be running > anywhere, just the same as I have now with the two independent clusters. > > > Thanks, > > > Antony. > > ‑‑ > "In fact I wanted to be John Cleese and it took me some time to realise that > > the job was already taken." > > ‑ Douglas Adams > > Please reply to the list; > please *don't* CC > me. > _______________________________________________ > Manage your subscription: > https://lists.clusterlabs.org/mailman/listinfo/users > > ClusterLabs home: https://www.clusterlabs.org/ _______________________________________________ Manage your subscription: https://lists.clusterlabs.org/mailman/listinfo/users ClusterLabs home: https://www.clusterlabs.org/