| Message ID | 20200508210027.462173-1-mmichels@redhat.com |
|---|---|
| State | Accepted |
| Commit | 43a6cf355455c70957893fb600b983c928173d5d |
| Headers | show |
| Series | [ovs-dev] RAFT: Add clarifying note for cluster/leave operation. | expand |
Acked-by: Han Zhou <hzhou@ovn.org> On Fri, May 8, 2020 at 2:00 PM Mark Michelson <mmichels@redhat.com> wrote: > We had a user express confusion about the state of a cluster after using > cluster/leave. The user had a three server cluster and used > cluster/leave to remove two servers from the cluster. The user expected > that the single server left would not function since the quorum of two > servers for a three server cluster was not met. > > In actuality, cluster/leave removes the server from the cluster and > alters the cluster size in the process. Thus the single remaining server > continued to function since quorum was reached. > > This documentation change makes it a bit more explicit that > cluster/leave alters the size of the cluster and cites the three server > down to one server case as an example. > > Reported-at: https://bugzilla.redhat.com/show_bug.cgi?id=1798158 > Signed-off-by: Mark Michelson <mmichels@redhat.com> > --- > ovsdb/ovsdb-server.1.in | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/ovsdb/ovsdb-server.1.in b/ovsdb/ovsdb-server.1.in > index 338f3bc29..6667553df 100644 > --- a/ovsdb/ovsdb-server.1.in > +++ b/ovsdb/ovsdb-server.1.in > @@ -347,6 +347,11 @@ until the server has left the cluster. > .IP > Once a server leaves a cluster, it may never rejoin it. Instead, > create a new server and join it to the cluster. > +.IP > +Note that removing the server from the cluster alters the total size > +of the cluster. For example, if you remove two servers from a three > +server cluster, then the "cluster" becomes a single functioning server. > +This does not result in a three server cluster that lacks quorum. > . > .IP "\fBcluster/kick \fIdb server\fR" > Start graceful removal of \fIserver\fR from \fIdb\fR's cluster, like > -- > 2.25.4 > > _______________________________________________ > dev mailing list > dev@openvswitch.org > https://mail.openvswitch.org/mailman/listinfo/ovs-dev >
Thanks, Mark and Han. I applied this to master. On Sun, May 10, 2020 at 11:59:24PM -0700, Han Zhou wrote: > Acked-by: Han Zhou <hzhou@ovn.org> > > On Fri, May 8, 2020 at 2:00 PM Mark Michelson <mmichels@redhat.com> wrote: > > > We had a user express confusion about the state of a cluster after using > > cluster/leave. The user had a three server cluster and used > > cluster/leave to remove two servers from the cluster. The user expected > > that the single server left would not function since the quorum of two > > servers for a three server cluster was not met. > > > > In actuality, cluster/leave removes the server from the cluster and > > alters the cluster size in the process. Thus the single remaining server > > continued to function since quorum was reached. > > > > This documentation change makes it a bit more explicit that > > cluster/leave alters the size of the cluster and cites the three server > > down to one server case as an example. > > > > Reported-at: https://bugzilla.redhat.com/show_bug.cgi?id=1798158 > > Signed-off-by: Mark Michelson <mmichels@redhat.com> > > --- > > ovsdb/ovsdb-server.1.in | 5 +++++ > > 1 file changed, 5 insertions(+) > > > > diff --git a/ovsdb/ovsdb-server.1.in b/ovsdb/ovsdb-server.1.in > > index 338f3bc29..6667553df 100644 > > --- a/ovsdb/ovsdb-server.1.in > > +++ b/ovsdb/ovsdb-server.1.in > > @@ -347,6 +347,11 @@ until the server has left the cluster. > > .IP > > Once a server leaves a cluster, it may never rejoin it. Instead, > > create a new server and join it to the cluster. > > +.IP > > +Note that removing the server from the cluster alters the total size > > +of the cluster. For example, if you remove two servers from a three > > +server cluster, then the "cluster" becomes a single functioning server. > > +This does not result in a three server cluster that lacks quorum. > > . > > .IP "\fBcluster/kick \fIdb server\fR" > > Start graceful removal of \fIserver\fR from \fIdb\fR's cluster, like > > -- > > 2.25.4 > > > > _______________________________________________ > > dev mailing list > > dev@openvswitch.org > > https://mail.openvswitch.org/mailman/listinfo/ovs-dev > > > _______________________________________________ > dev mailing list > dev@openvswitch.org > https://mail.openvswitch.org/mailman/listinfo/ovs-dev
diff --git a/ovsdb/ovsdb-server.1.in b/ovsdb/ovsdb-server.1.in index 338f3bc29..6667553df 100644 --- a/ovsdb/ovsdb-server.1.in +++ b/ovsdb/ovsdb-server.1.in @@ -347,6 +347,11 @@ until the server has left the cluster. .IP Once a server leaves a cluster, it may never rejoin it. Instead, create a new server and join it to the cluster. +.IP +Note that removing the server from the cluster alters the total size +of the cluster. For example, if you remove two servers from a three +server cluster, then the "cluster" becomes a single functioning server. +This does not result in a three server cluster that lacks quorum. . .IP "\fBcluster/kick \fIdb server\fR" Start graceful removal of \fIserver\fR from \fIdb\fR's cluster, like
We had a user express confusion about the state of a cluster after using cluster/leave. The user had a three server cluster and used cluster/leave to remove two servers from the cluster. The user expected that the single server left would not function since the quorum of two servers for a three server cluster was not met. In actuality, cluster/leave removes the server from the cluster and alters the cluster size in the process. Thus the single remaining server continued to function since quorum was reached. This documentation change makes it a bit more explicit that cluster/leave alters the size of the cluster and cites the three server down to one server case as an example. Reported-at: https://bugzilla.redhat.com/show_bug.cgi?id=1798158 Signed-off-by: Mark Michelson <mmichels@redhat.com> --- ovsdb/ovsdb-server.1.in | 5 +++++ 1 file changed, 5 insertions(+)