docs/vfs_ceph: add CTDB_SAMBA_SKIP_SHARE_CHECK=yes caveat

Mostly copied from the vfs_gluster manpage: the CephFS share path is not
locally mounted, which breaks the ctdb_check_directories_probe() check.

Signed-off-by: David Disseldorp <ddiss@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
Autobuild-User(master): Jeremy Allison <jra@samba.org>
Autobuild-Date(master): Fri Jul  6 23:19:02 CEST 2018 on sn-devel-144

(cherry picked from commit 0cd44821f3889067620d685344c3eaf913a31329)

diff --git a/docs-xml/manpages/vfs_ceph.8.xml b/docs-xml/manpages/vfs_ceph.8.xml
index 757b20ff4892b23a19540b5bb7a41b34663de919..c6de28a8144d41a27be4dce3e4276affbc0f1a61 100644 (file)
--- a/docs-xml/manpages/vfs_ceph.8.xml
+++ b/docs-xml/manpages/vfs_ceph.8.xml
@@ -66,6 +66,17 @@
                <smbconfoption name="kernel share modes">no</smbconfoption>
        </programlisting>
 
+       <para>
+               Since <command>vfs_ceph</command> does not require a filesystem
+               mount, the share <command>path</command> is treated differently:
+               it is interpreted as an absolute path within the Ceph filesystem
+               on the attached Ceph cluster.
+               In a ctdb cluster environment where ctdb manages Samba,
+               <command>CTDB_SAMBA_SKIP_SHARE_CHECK=yes</command> must be
+               configured to disable local share path checks, otherwise ctdb
+               will not reach a healthy state.
+       </para>
+
        <para>
                Note that currently <command>kernel share modes</command> have
                to be disabled in a share running with the CephFS vfs module for