3 7 3 7 1 transfer updating

Discovery is also called periodically by MERGE2 (see Section 7.4.1, “MERGE2”), to see if we have diverging cluster membership information.

3 7 3 7 1 transfer updating-873 7 3 7 1 transfer updating-143 7 3 7 1 transfer updating-80

IP multicast packets send on a host P will therefore not be received by anyone on P. Specifying TCP in your protocol stack tells JGroups to use TCP to send messages between cluster members.

Instead of using a multicast bus, the cluster members create a mesh of TCP connections.

Subsequent requests for the same physical address will therefore be spaced at least who_has_cache_timeout ms apart UDP uses IP multicast for sending messages to all members of a group and UDP datagrams for unicast messages (sent to a single member).

When started, it opens a unicast and multicast socket: the unicast socket is used to send/receive unicast messages, whereas the multicast socket sends and receives multicast messages.

If running across subnets, an admin has to ensure that IP multicast is enabled across subnets.

Last modified 20-Feb-2018 10:40