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7.5. Remote Replication Nodes

Used for HA only. A remote replication node is a representation of another virtualhost node in the group. Remote replication nodes are not created directly. Instead the system automatically creates a remote replication node for every node in the group. It serves to provide a view of the whole group from every node in the system.

7.5.1. Attributes

  • Name the remote replication node. This is the name of the remote virtualhost node

  • Role. Indicates the role that the remote node is playing in the group at this moment.

    • MASTER - Remote node is a master.

    • REPLICA - Remote node is a replica.

    • UNREACHABLE - Remote node unreachable from this node. This remote note may be down, or an network problem may prevent it from being contacted.

  • Join time. Time when first contact was established with this node.

  • Last known transaction id. Last transaction id reported processed by node. This is an internal transaction counter and does not relate to any value available to the messaging clients. This value can only be used to determine the node is up to date relative to others in the group.

7.5.2. Children

None

7.5.3. Lifecycle

  • Delete. Causes the remote node to be permanently removed from the group. This operation should be used when the virtualhost node cannot be deleted from its own Broker, for instance, if a Broker has been destroyed by machine failure.

7.5.4. Operations

  • Transfer Master. Initiates a process where a master is moved to anther node in the group. The transfer sequence is as follows.

    1. Group waits until the proposed master is reasonable up to date.

    2. Any in-flight transactions on the current master are blocked.

    3. The current master awaits the proposed master to become up to date.

    4. The mastership is transferred. This will automatically disconnect messaging clients from the old master, and in-flight transactions are rolled back. Messaging clients reconnect to the new master.

    5. The old master will rejoin as a replica.