From 34eac41997ba54860a868f14f7704e73a78b7612 Mon Sep 17 00:00:00 2001
From: Kamil Madac <kamil.madac@gmail.com>
Date: Fri, 15 Mar 2024 14:14:47 +0100
Subject: [PATCH] doc: added note about monitor ips update during failover

IP addresses in csi-config-map needs to be changed after failover
to secondary site. Without this change, applications can't use
mirrored rbd images.

Signed-off-by: Kamil Madac <kamil.madac@gmail.com>
---
 docs/design/proposals/clusterid-mapping.md | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/docs/design/proposals/clusterid-mapping.md b/docs/design/proposals/clusterid-mapping.md
index 9e72205f341..b4c3ebdbd54 100644
--- a/docs/design/proposals/clusterid-mapping.md
+++ b/docs/design/proposals/clusterid-mapping.md
@@ -178,3 +178,10 @@ operation from the primary cluster to a remote cluster. The existing volumes
 that are created on the remote cluster does not require any mapping as the
 volumeHandle already contains the required information about the local cluster (
 clusterID, poolID etc).
+
+**Note:-** To use a mirrored and promoted RBD image on a secondary site during a
+failover, you need to replace the primary monitor addresses with the IP
+addresses of the secondary cluster in the ceph-csi-config. Otherwise, Ceph-CSI
+won't be able to use the volumes, and application pods will become stuck in the
+`ContainerCreating` state. Thus, during failover, both clusters will have the
+same monitor IP addresses.