From 3f10fb924f8b7ab2183458496e26a6a4f5b25a72 Mon Sep 17 00:00:00 2001 From: Rachel Elledge Date: Fri, 30 May 2025 14:08:22 -0500 Subject: [PATCH 1/2] DOC-3587 RS: Clarified quorum loss check and warning when activating maintenance mode --- content/operate/rs/7.4/clusters/maintenance-mode.md | 6 ++++-- content/operate/rs/7.8/clusters/maintenance-mode.md | 6 ++++-- content/operate/rs/clusters/maintenance-mode.md | 6 ++++-- 3 files changed, 12 insertions(+), 6 deletions(-) diff --git a/content/operate/rs/7.4/clusters/maintenance-mode.md b/content/operate/rs/7.4/clusters/maintenance-mode.md index 1b5cba0433..143c0786c1 100644 --- a/content/operate/rs/7.4/clusters/maintenance-mode.md +++ b/content/operate/rs/7.4/clusters/maintenance-mode.md @@ -17,9 +17,11 @@ Use maintenance mode to prevent data loss during hardware patching or operating When you activate maintenance mode, Redis Enterprise does the following: -1. Checks whether a shut down of the node will cause quorum loss. If so, maintenance mode will not turn on. +1. Checks whether shutting down this node would cause quorum loss. If so, maintenance mode will not activate. - Maintenance mode does not protect against quorum loss. If you activate maintenance mode for the majority of nodes in a cluster and restart them simultaneously, quorum is lost, which can lead to data loss. + {{}} +This check does not verify that the majority of nodes in the cluster are not in maintenance mode. Do not activate maintenance mode on the majority of nodes and restart them simultaneously, as this can cause quorum loss and data loss. + {{}} 1. If no maintenance mode snapshots already exist or if you use `overwrite_snapshot` when you activate maintenance mode, Redis Enterprise creates a new node snapshot that records the node's shard and endpoint configuration. diff --git a/content/operate/rs/7.8/clusters/maintenance-mode.md b/content/operate/rs/7.8/clusters/maintenance-mode.md index 8d6cbc4305..dcdcbffc11 100644 --- a/content/operate/rs/7.8/clusters/maintenance-mode.md +++ b/content/operate/rs/7.8/clusters/maintenance-mode.md @@ -17,9 +17,11 @@ Use maintenance mode to prevent data loss during hardware patching or operating When you activate maintenance mode, Redis Enterprise does the following: -1. Checks whether a shut down of the node will cause quorum loss. If so, maintenance mode will not turn on. +1. Checks whether shutting down this node would cause quorum loss. If so, maintenance mode will not activate. - Maintenance mode does not protect against quorum loss. If you activate maintenance mode for the majority of nodes in a cluster and restart them simultaneously, quorum is lost, which can lead to data loss. + {{}} +This check does not verify that the majority of nodes in the cluster are not in maintenance mode. Do not activate maintenance mode on the majority of nodes and restart them simultaneously, as this can cause quorum loss and data loss. + {{}} 1. If no maintenance mode snapshots already exist or if you use `overwrite_snapshot` when you activate maintenance mode, Redis Enterprise creates a new node snapshot that records the node's shard and endpoint configuration. diff --git a/content/operate/rs/clusters/maintenance-mode.md b/content/operate/rs/clusters/maintenance-mode.md index 7db1df5afc..383d7dac2a 100644 --- a/content/operate/rs/clusters/maintenance-mode.md +++ b/content/operate/rs/clusters/maintenance-mode.md @@ -16,9 +16,11 @@ Use maintenance mode to prevent data loss during hardware patching or operating When you activate maintenance mode, Redis Enterprise does the following: -1. Checks whether a shut down of the node will cause quorum loss. If so, maintenance mode will not turn on. +1. Checks whether shutting down this node would cause quorum loss. If so, maintenance mode will not activate. - Maintenance mode does not protect against quorum loss. If you activate maintenance mode for the majority of nodes in a cluster and restart them simultaneously, quorum is lost, which can lead to data loss. + {{}} +This check does not verify that the majority of nodes in the cluster are not in maintenance mode. Do not activate maintenance mode on the majority of nodes and restart them simultaneously, as this can cause quorum loss and data loss. + {{}} 1. If no maintenance mode snapshots already exist or if you use `overwrite_snapshot` when you activate maintenance mode, Redis Enterprise creates a new node snapshot that records the node's shard and endpoint configuration. From 9524220cef7af8a273e6208fa9df6705ed2d107f Mon Sep 17 00:00:00 2001 From: Rachel Elledge Date: Mon, 2 Jun 2025 16:19:35 -0500 Subject: [PATCH 2/2] DOC-3587 Adjusted wording of maintenance mode quorum check --- content/operate/rs/7.4/clusters/maintenance-mode.md | 4 ++-- content/operate/rs/7.8/clusters/maintenance-mode.md | 4 ++-- content/operate/rs/clusters/maintenance-mode.md | 4 ++-- 3 files changed, 6 insertions(+), 6 deletions(-) diff --git a/content/operate/rs/7.4/clusters/maintenance-mode.md b/content/operate/rs/7.4/clusters/maintenance-mode.md index 143c0786c1..1d324639e4 100644 --- a/content/operate/rs/7.4/clusters/maintenance-mode.md +++ b/content/operate/rs/7.4/clusters/maintenance-mode.md @@ -17,10 +17,10 @@ Use maintenance mode to prevent data loss during hardware patching or operating When you activate maintenance mode, Redis Enterprise does the following: -1. Checks whether shutting down this node would cause quorum loss. If so, maintenance mode will not activate. +1. Checks whether the cluster has enough active nodes to maintain quorum if one goes down. If taking a node offline would cause quorum loss, maintenance mode will not activate. {{}} -This check does not verify that the majority of nodes in the cluster are not in maintenance mode. Do not activate maintenance mode on the majority of nodes and restart them simultaneously, as this can cause quorum loss and data loss. +This check does not consider if other nodes are already in maintenance mode. Do not put the majority of nodes into maintenance mode and restart them simultaneously, as this can cause the cluster to lose quorum and lead to data loss. {{}} 1. If no maintenance mode snapshots already exist or if you use `overwrite_snapshot` when you activate maintenance mode, Redis Enterprise creates a new node snapshot that records the node's shard and endpoint configuration. diff --git a/content/operate/rs/7.8/clusters/maintenance-mode.md b/content/operate/rs/7.8/clusters/maintenance-mode.md index dcdcbffc11..62db48a8e2 100644 --- a/content/operate/rs/7.8/clusters/maintenance-mode.md +++ b/content/operate/rs/7.8/clusters/maintenance-mode.md @@ -17,10 +17,10 @@ Use maintenance mode to prevent data loss during hardware patching or operating When you activate maintenance mode, Redis Enterprise does the following: -1. Checks whether shutting down this node would cause quorum loss. If so, maintenance mode will not activate. +1. Checks whether the cluster has enough active nodes to maintain quorum if one goes down. If taking a node offline would cause quorum loss, maintenance mode will not activate. {{}} -This check does not verify that the majority of nodes in the cluster are not in maintenance mode. Do not activate maintenance mode on the majority of nodes and restart them simultaneously, as this can cause quorum loss and data loss. +This check does not consider if other nodes are already in maintenance mode. Do not put the majority of nodes into maintenance mode and restart them simultaneously, as this can cause the cluster to lose quorum and lead to data loss. {{}} 1. If no maintenance mode snapshots already exist or if you use `overwrite_snapshot` when you activate maintenance mode, Redis Enterprise creates a new node snapshot that records the node's shard and endpoint configuration. diff --git a/content/operate/rs/clusters/maintenance-mode.md b/content/operate/rs/clusters/maintenance-mode.md index 383d7dac2a..e324ccaceb 100644 --- a/content/operate/rs/clusters/maintenance-mode.md +++ b/content/operate/rs/clusters/maintenance-mode.md @@ -16,10 +16,10 @@ Use maintenance mode to prevent data loss during hardware patching or operating When you activate maintenance mode, Redis Enterprise does the following: -1. Checks whether shutting down this node would cause quorum loss. If so, maintenance mode will not activate. +1. Checks whether the cluster has enough active nodes to maintain quorum if one goes down. If taking a node offline would cause quorum loss, maintenance mode will not activate. {{}} -This check does not verify that the majority of nodes in the cluster are not in maintenance mode. Do not activate maintenance mode on the majority of nodes and restart them simultaneously, as this can cause quorum loss and data loss. +This check does not consider if other nodes are already in maintenance mode. Do not put the majority of nodes into maintenance mode and restart them simultaneously, as this can cause the cluster to lose quorum and lead to data loss. {{}} 1. If no maintenance mode snapshots already exist or if you use `overwrite_snapshot` when you activate maintenance mode, Redis Enterprise creates a new node snapshot that records the node's shard and endpoint configuration.