com.lightbend.akka.sbr

Class SplitBrainResolver.StaticQuorum

java.lang.Object

com.lightbend.akka.sbr.SplitBrainResolver.Strategy

com.lightbend.akka.sbr.SplitBrainResolver.StaticQuorum

All Implemented Interfaces:

akka.actor.NoSerializationVerificationNeeded

Enclosing class:

SplitBrainResolver

public static class SplitBrainResolver.StaticQuorum
extends SplitBrainResolver.Strategy

Down the unreachable nodes if the number of remaining nodes are greater than or equal to the given quorumSize. Otherwise down the reachable nodes, i.e. it will shut down that side of the partition. In other words, the quorumSize defines the minimum number of nodes that the cluster must have to be operational. If there are unreachable nodes when starting up the cluster, before reaching this limit, the cluster may shutdown itself immediately. This is not an issue if you start all nodes at approximately the same time.

Note that you must not add more members to the cluster than quorumSize * 2 - 1, because then both sides may down each other and thereby form two separate clusters. For example, quorum quorumSize configured to 3 in a 6 node cluster may result in a split where each side consists of 3 nodes each, i.e. each side thinks it has enough nodes to continue by itself. A warning is logged if this recommendation is violated.

If the role is defined the decision is based only on members with that role.

It is only counting members within the own data center.

Constructor Summary

Constructors

Constructor and Description
StaticQuorum(java.lang.String selfDc, int quorumSize, scala.Option<java.lang.String> role)

Method Summary

Modifier and Type	Method and Description
SplitBrainResolver.Decision	decide()
boolean	isTooManyMembers()
int	quorumSize()
scala.Option<java.lang.String>	role()

Methods inherited from class com.lightbend.akka.sbr.SplitBrainResolver.Strategy

add, addReachable, addUnreachable, allMembersInDC, hasIndirectlyConnected, indirectlyConnected, isAllUnreachableDownOrExiting, joining, lease, members, members, membersWithRole, membersWithRole, nodesToDown, nodesToDown$default$1, ordering, reachability, reachableMembers, reachableMembers, reachableMembersWithRole, reachableMembersWithRole, remove, reverseDecision, seenBy, selfDc, setReachability, setSeenBy, unreachable, unreachable, unreachableButNotIndirectlyConnected, unreachableMembers, unreachableMembers, unreachableMembersWithRole, unreachableMembersWithRole

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

StaticQuorum

public StaticQuorum(java.lang.String selfDc,
                    int quorumSize,
                    scala.Option<java.lang.String> role)

Method Detail

decide

public SplitBrainResolver.Decision decide()

Specified by:

decide in class SplitBrainResolver.Strategy

isTooManyMembers

public boolean isTooManyMembers()

quorumSize

public int quorumSize()

role

public scala.Option<java.lang.String> role()

Specified by:

role in class SplitBrainResolver.Strategy