RBD mirror uses cluster name when configuring its peer [1,2] [1] http://docs.ceph.com/docs/master/rbd/rbd-mirroring/#add-cluster-peer [2] https://access.redhat.com/documentation/en-us/red_hat_ceph_storage/2/html/block_device_guide/block_device_mirroring#configuring_one_way_mirroring On Thu, Jun 08, 2017 at 07:37:23PM +0000, Sage Weil wrote: > At CDM yesterday we talked about removing the ability to name your ceph > clusters. There are a number of hurtles that make it difficult to fully > get rid of this functionality, not the least of which is that some > (many?) deployed clusters make use of it. We decided that the most we can > do at this point is remove support for it in ceph-deploy and ceph-ansible > so that no new clusters or deployed nodes use it. > > The first PR in this effort: > > https://github.com/ceph/ceph-deploy/pull/441 > > Background: > > The cluster name concept was added to allow multiple clusters to have > daemons coexist on the same host. At the type it was a hypothetical > requirement for a user that never actually made use of it, and the > support is kludgey: > > - default cluster name is 'ceph' > - default config is /etc/ceph/$cluster.conf, so that the normal > 'ceph.conf' still works > - daemon data paths include the cluster name, > /var/lib/ceph/osd/$cluster-$id > which is weird (but mostly people are used to it?) > - any cli command you want to touch a non-ceph cluster name > needs -C $name or --cluster $name passed to it. > > Also, as of jewel, > > - systemd only supports a single cluster per host, as defined by $CLUSTER > in /etc/{sysconfig,default}/ceph > > which you'll notice removes support for the original "requirement". > > Also note that you can get the same effect by specifying the config path > explicitly (-c /etc/ceph/foo.conf) along with the various options that > substitute $cluster in (e.g., osd_data=/var/lib/ceph/osd/$cluster-$id). > > > Crap preventing us from removing this entirely: > > - existing daemon directories for existing clusters > - various scripts parse the cluster name out of paths > > > Converting an existing cluster "foo" back to "ceph": > > - rename /etc/ceph/foo.conf -> ceph.conf > - rename /var/lib/ceph/*/foo-* -> /var/lib/ceph/*/ceph-* > - remove the CLUSTER=foo line in /etc/{default,sysconfig}/ceph > - reboot > > > Questions: > > - Does anybody on the list use a non-default cluster name? > - If so, do you have a reason not to switch back to 'ceph'? > > Thanks! > sage > -- > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Mykola Golub -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
