From: Yan, Zheng Date: Tue, 17 Apr 2018 11:46:30 +0000 (+0800) Subject: doc: add release notes for cephfs snapshot X-Git-Tag: v13.1.0~2^2~4 X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=24bb126dbe443746de35167f8bd4d03c9644a5c0;p=ceph.git doc: add release notes for cephfs snapshot Signed-off-by: "Yan, Zheng" --- diff --git a/PendingReleaseNotes b/PendingReleaseNotes index 43ad2e2758a..3ff0b84d859 100644 --- a/PendingReleaseNotes +++ b/PendingReleaseNotes @@ -63,6 +63,25 @@ significantly reducing the time of loading inodes for open files. MDS creates the table automatically if it does not exist. + * CephFS snapshot is now stable and enabled by default on new filesystems. + To enable snapshot on existing filesystems, use command: + - ceph fs set allow_new_snaps + + The on-disk format of snapshot metadata has changed. The old format + metadata can not be properly handled in multiple active MDS configuration. + To guarantee all snapshot metadata on existing filesystems get updated, + perform the sequence of upgrading the MDS cluster strictly. + + See http://docs.ceph.com/docs/master/cephfs/upgrading/ + + For filesystems that have ever enabled snapshot, the multiple-active MDS + feature is disabled by the new version MON. This will cause the "restore + previous max_mds" step in above URL to fail. To re-enable the feature, + either delete all old snapshots or scrub the whole filesystem: + + - ceph daemon scrub_path / force recursive repair + - ceph daemon scrub_path '~mdsdir' force recursive repair + * *RBD* * The RBD C API's rbd_discard method now enforces a maximum length of