From f87ff22b1b8d1fff333e184b392488a7d7fdf916 Mon Sep 17 00:00:00 2001
From: Eric Harney <eharney@redhat.com>
Date: Wed, 28 Feb 2018 11:55:03 -0500
Subject: [PATCH] RBD: Add comment about multiattach support

Add a comment discouraging multiattach support
being flipped on without proper investigation and
design.

Change-Id: If9885dd3a2e79af4249418fedfe8f3bf73ad2ef5
---
 cinder/volume/drivers/rbd.py | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/cinder/volume/drivers/rbd.py b/cinder/volume/drivers/rbd.py
index 885cf803198..1031ddd6421 100644
--- a/cinder/volume/drivers/rbd.py
+++ b/cinder/volume/drivers/rbd.py
@@ -473,6 +473,13 @@ class RBDDriver(driver.CloneableImageVD,
             'provisioned_capacity_gb': 0,
             'reserved_percentage': (
                 self.configuration.safe_get('reserved_percentage')),
+            # NOTE(eharney): Do not enable multiattach for this driver.
+            # For multiattach to work correctly, the exclusive-lock
+            # feature required by ceph journaling must be disabled.
+            # This has implications for replication and other Cinder
+            # operations.
+            # Multiattach support for this driver will be investigated
+            # as multi-attach support in Cinder matures.
             'multiattach': False,
             'thin_provisioning_support': True,
             'max_over_subscription_ratio': (