doc/glosary.rst: add "Ceph Block Device" term

Add a definition for "Ceph Block Device".

Signed-off-by: Zac Dover <zac.dover@gmail.com>

diff --git a/doc/glossary.rst b/doc/glossary.rst
index c427141f99268b43d2612408d65f8400684e8067..27801bd4560a06e0972269d1e0dcc6cad1b3b4be 100644 (file)
--- a/doc/glossary.rst
+++ b/doc/glossary.rst
@@ -22,6 +22,13 @@ reflect either technical terms or legacy ways of referring to Ceph systems.
 
        Ceph
        Ceph Block Device
+                A software instrument that orchestrates the storage of
+                block-based data in Ceph. Ceph Block Device (also called "RBD",
+                or "RADOS block device") splits block-based application data
+                into "chunks". RADOS stores these chunks as objects. Ceph Block
+                Device orchestrates the storage of those objects across the
+                storage cluster. See also :term:`RBD`.
+
        Ceph Block Storage
                 The block storage "product," service or capabilities when used
                 in conjunction with ``librbd``, a hypervisor such as QEMU or