On Thu, 2019-02-14 at 10:35 +0800, Marvin Zhang wrote: > On Thu, Feb 14, 2019 at 8:09 AM Jeff Layton <jlayton@xxxxxxxxxxxxxxx> wrote: > > > Hi, > > > As http://docs.ceph.com/docs/master/cephfs/nfs/ says, it's OK to > > > config active/passive NFS-Ganesha to use CephFs. My question is if we > > > can use active/active nfs-ganesha for CephFS. > > > > (Apologies if you get two copies of this. I sent an earlier one from the > > wrong account and it got stuck in moderation) > > > > You can, with the new rados-cluster recovery backend that went into > > ganesha v2.7. See here for a bit more detail: > > > > https://jtlayton.wordpress.com/2018/12/10/deploying-an-active-active-nfs-cluster-over-cephfs/ > > > > ...also have a look at the ceph.conf file in the ganesha sources. > > > > > In my thought, only state consistance should we think about. > > > 1. Lock support for Active/Active. Even each nfs-ganesha sever mantain > > > the lock state, the real lock/unlock will call > > > ceph_ll_getlk/ceph_ll_setlk. So Ceph cluster will handle the lock > > > safely. > > > 2. Delegation support Active/Active. It's similar question 1, > > > ceph_ll_delegation will handle it safely. > > > 3. Nfs-ganesha cache support Active/Active. As > > > https://github.com/nfs-ganesha/nfs-ganesha/blob/next/src/config_samples/ceph.conf > > > describes, we can config cache size as size 1. > > > 4. Ceph-FSAL cache support Active/Active. Like other CephFs client, > > > there is no issues for cache consistance. > > > > The basic idea with the new recovery backend is to have the different > > NFS ganesha heads coordinate their recovery grace periods to prevent > > stateful conflicts. > > > > The one thing missing at this point is delegations in an active/active > > configuration, but that's mainly because of the synchronous nature of > > libcephfs. We have a potential fix for that problem but it requires work > > in libcephfs that is not yet done. > [marvin] So we should disable delegation on active/active and set the > conf like this. Is it right? > NFSv4 > { > Delegations = false; > } Yes. -- Jeff Layton <jlayton@xxxxxxxxxxxxxxx> _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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