Signatures
----------
-In Ceph Bobtail and subsequent versions, we prefer that Ceph authenticate all
-ongoing messages between the entities using the session key set up for that
-initial authentication. However, Argonaut and earlier Ceph daemons do not know
-how to perform ongoing message authentication. To maintain backward
-compatibility (e.g., running both Botbail and Argonaut daemons in the same
-cluster), message signing is **off** by default. If you are running Bobtail or
-later daemons exclusively, configure Ceph to require signatures.
+Ceph performs a signature check that provides some limited protection
+against messages being tampered with in flight (e.g., by a "man in the
+middle" attack).
Like other parts of Ceph authentication, Ceph provides fine-grained control so
you can enable/disable signatures for service messages between the client and
Ceph, and you can enable/disable signatures for messages between Ceph daemons.
+Note that even with signatures enabled data is not encrypted in
+flight.
``cephx require signatures``
traffic between the Ceph Client and the Ceph Storage Cluster, and
between daemons comprising the Ceph Storage Cluster.
+ Ceph Argonaut and Linux kernel versions prior to 3.19 do
+ not support signatures; if such clients are in use this
+ option can be turned off to allow them to connect.
+
:Type: Boolean
:Required: No
:Default: ``false``
``cephx sign messages``
:Description: If the Ceph version supports message signing, Ceph will sign
- all messages so they cannot be spoofed.
+ all messages so they are more difficult to spoof.
:Type: Boolean
:Default: ``true``