From e8029bdc4edaf77af5ae7f5a4ede259f4c75bff2 Mon Sep 17 00:00:00 2001 From: Anthony Date: Fri, 25 Aug 2017 00:41:07 +0800 Subject: [PATCH] Update highly-available-master.md (#5006) * Update highly-available-master.md --- docs/tasks/administer-cluster/highly-available-master.md | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/docs/tasks/administer-cluster/highly-available-master.md b/docs/tasks/administer-cluster/highly-available-master.md index e15a769770..f6519fad53 100644 --- a/docs/tasks/administer-cluster/highly-available-master.md +++ b/docs/tasks/administer-cluster/highly-available-master.md @@ -92,11 +92,11 @@ $ KUBE_GCE_ZONE=replica-zone KUBE_REPLICATE_EXISTING_MASTER=true ./cluster/kube- ## Best practices for replicating masters for HA clusters -* Try to place masters replicas in different zones. During a zone failure, all master placed inside the zone will fail. +* Try to place master replicas in different zones. During a zone failure, all masters placed inside the zone will fail. To survive zone failure, also place nodes in multiple zones (see [multiple-zones](/docs/admin/multiple-zones/) for details). -* Do not use a cluster with two master replicas. Consensus on a two replica cluster requires both replicas running when changing persistent state. +* Do not use a cluster with two master replicas. Consensus on a two-replica cluster requires both replicas running when changing persistent state. As a result, both replicas are needed and a failure of any replica turns cluster into majority failure state. A two-replica cluster is thus inferior, in terms of HA, to a single replica cluster.