pveceph: improve documentation for destroying cephfs

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>

diff --git a/pveceph.adoc b/pveceph.adoc
index aa7a20f3cd3bb7b73efc0c20e371796bb31f7e3c..cceb1ca2863267e3c96915782d03dc85285c11e6 100644 (file)
--- a/pveceph.adoc
+++ b/pveceph.adoc
@@ -809,28 +809,53 @@ Destroy CephFS
 WARNING: Destroying a CephFS will render all of its data unusable. This cannot be
 undone!
 
-If you really want to destroy an existing CephFS, you first need to stop or
-destroy all metadata servers (`M̀DS`). You can destroy them either via the web
-interface or via the command line interface, by issuing
+To completely an cleanly remove a CephFS, the following steps are necessary:
 
+* Disconnect every non-{PVE} client (e.g. unmount the CephFS in guests).
+* Disable all related CephFS {PVE} storage entries (to prevent it from being
+  automatically mounted).
+* Remove all used resources from guests (e.g. ISOs) that are on the CephFS you
+  want to destroy.
+* Unmount the CephFS storages on all cluster nodes manually with
++
 ----
-pveceph mds destroy NAME
+umount /mnt/pve/<STORAGE-NAME>
 ----
-on each {pve} node hosting an MDS daemon.
-
-Then, you can remove (destroy) the CephFS by issuing
++
+Where `<STORAGE-NAME>` is the name of the CephFS storage in your {PVE}.
 
+* Now make sure that no metadata server (`MDS`) is running for that CephFS,
+  either by stopping or destroying them. This can be done either via the web
+  interface or via the command line interface, by issuing:
++
+----
+pveceph stop --service mds.NAME
 ----
-ceph fs rm NAME --yes-i-really-mean-it
++
+to stop them, or
++
+----
+pveceph mds destroy NAME
 ----
-on a single node hosting Ceph. After this, you may want to remove the created
-data and metadata pools, this can be done either over the Web GUI or the CLI
-with:
++
+to destroy them.
++
+Note that standby servers will automatically be promoted to active when an
+active `MDS` is stopped or removed, so it is best to first stop all standby
+servers.
 
+* Now you can destroy the CephFS with
++
 ----
-pveceph pool destroy NAME
+pveceph fs destroy NAME --remove-storages --remove-pools
 ----
++
+This will automatically destroy the underlying ceph pools as well as remove
+the storages from pve config.
 
+After these steps, the CephFS should be completely removed and if you have
+other CephFS instances, the stopped metadata servers can be started again
+to act as standbys.
 
 Ceph maintenance
 ----------------