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Justin Bertram commented on ARTEMIS-4555: ----------------------------------------- This is a well-known danger. In fact, there's a whole chapter in [the documentation|https://activemq.apache.org/components/artemis/documentation/latest/network-isolation.html#network-isolation-split-brain] about it. You should deploy at least 3 HA pairs to establish a proper quorum for voting and set {{<vote-on-replication-failure>true</vote-on-replication-failure>}} on the backup. The next release will have better documentation around both the high level explanation and the low-level configuration for split-brain scenarios. > ActiveMq Artemis can have two live brokers in one cluster at one time > --------------------------------------------------------------------- > > Key: ARTEMIS-4555 > URL: https://issues.apache.org/jira/browse/ARTEMIS-4555 > Project: ActiveMQ Artemis > Issue Type: Bug > Components: Broker, Clustering > Affects Versions: 2.30.0 > Reporter: Sophia > Priority: Major > > An ActiveMq Artemis cluster can have two live brokers that can receive > requests at the same time. This happens if the communication drops between > the live broker and the passive broker. > > We deploy ActiveMQ Artemis v(2.30.0) on a five nodes cluster with Ubuntu > 18.04. The cluster consists of a master broker and three backup brokers. We > deploy classic replication with three backups for the master broker. One of > the backup brokers announces its status as a passive backup for the live > broker. > > If the communication breaks between the live and the passive broker, the > passive broker changes its status to live and starts accepting messages. A > warning message appears on all nodes telling that there are two live brokers > in the cluster. When we fix the network problem, the cluster still has two > live brokers that can accept requests. Although we set allow-fail-back to > true on the backups config which should force the backup that has become live > to automatically stop when the live is back. -- This message was sent by Atlassian Jira (v8.20.10#820010)