From 68a7a55927916ae2ee3b351eda5764f71bbedff0 Mon Sep 17 00:00:00 2001 From: ravind Date: Wed, 20 Apr 2016 10:55:47 -0400 Subject: [PATCH] DOCS-2474: mirrored mongod must be within 30 secs --- source/core/sharded-cluster-config-servers.txt | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/source/core/sharded-cluster-config-servers.txt b/source/core/sharded-cluster-config-servers.txt index fd9d1494d39..03b0b8ac4e8 100644 --- a/source/core/sharded-cluster-config-servers.txt +++ b/source/core/sharded-cluster-config-servers.txt @@ -40,9 +40,15 @@ Replica Set Config Servers .. include:: /includes/fact-config-server-replica-set-restrictions.rst Earlier versions of MongoDB required *exactly three* mirrored -:program:`mongod` instances to act as the config servers. MongoDB 3.2 -deprecates the use of three mirrored :program:`mongod` instances for -config servers. +:program:`mongod` instances to act as the config servers. If you are using +*mirrored* config servers, each server's system clock must be within 30 +seconds of each other server for the distributed lock manager to work +properly. With *mirrored* config servers, minimize clock skew by running the +network time protocol (NTP) ``ntpd`` on your servers. MongoDB 3.2 deprecates +the use of three mirrored :program:`mongod` instances for config servers. + +With replica set config servers, clock skew does not affect distributed lock +management. Each sharded cluster must have its own config servers. Do not use the same config servers for different sharded clusters.