On Thu, Nov 20, 2014 at 9:08 AM, Dan van der Ster <daniel.vanderster@xxxxxxx> wrote: > Hi all, > What is compatibility/incompatibility of dumpling clients to talk to firefly > and giant clusters? We sadly don't have a good matrix about this yet, but in general you should assume that anything which changed the way the data is physically placed on the cluster will prevent them from communicating; if you don't enable those features then they should remain compatible. In particular > I know that tunables=firefly will prevent dumpling > clients from talking to a firefly cluster, but how about the existence or > not of erasure pools? As you mention, updating the tunables will prevent old clients from accessing them (although that shouldn't be the case in future now that they're all set by the crush map for later interpretation). Erasure pools are a special case (precisely because people had issues with them) and you should be able to communicate with a cluster that has EC pools while using old clients — but, no: > Can a dumpling client talk to a Firefly/Giant erasure > pool if the tunables are still dumping? Definitely not. EC pools use a slightly different CRUSH algorithm than the old clients could, among many other things. -Greg _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
 |