On Wed, 2019-11-20 at 03:29 -0500, xiubli@xxxxxxxxxx wrote:
> From: Xiubo Li <xiubli@xxxxxxxxxx>
>
> In case the max_mds > 1 in MDS cluster and there is no any standby
> MDS and all the max_mds MDSs are in up:active state, if one of the
> up:active MDSs is dead, the m->m_num_laggy in kclient will be 1.
> Then the mount will fail without considering other healthy MDSs.
>
> Only when all the MDSs in the cluster are laggy will treat the
> cluster as not be available.
>
> Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx>
> ---
> fs/ceph/mdsmap.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/ceph/mdsmap.c b/fs/ceph/mdsmap.c
> index 471bac335fae..8b4f93e5b468 100644
> --- a/fs/ceph/mdsmap.c
> +++ b/fs/ceph/mdsmap.c
> @@ -396,7 +396,7 @@ bool ceph_mdsmap_is_cluster_available(struct ceph_mdsmap *m)
> return false;
> if (m->m_damaged)
> return false;
> - if (m->m_num_laggy > 0)
> + if (m->m_num_laggy == m->m_num_mds)
> return false;
> for (i = 0; i < m->m_num_mds; i++) {
> if (m->m_info[i].state == CEPH_MDS_STATE_ACTIVE)
Given that laggy servers are still expected to be "in" the cluster,
should we just eliminate this check altogether? It seems like we'd still
want to allow a mount to occur even if the cluster is lagging.
--
Jeff Layton <jlayton@xxxxxxxxxx>
