Failure detection protocol based on a ring of TCP sockets created between group members. Each member in a group connects to its neighbor (last member connects to first) thus forming a ring. Member B is suspected when its neighbor A detects abnormally closed TCP socket (presumably due to a node B crash). However, if a member B is about to leave gracefully, it lets its neighbor A know, so that it does not become suspected.


    One FD_SOCK disadvantage is that hung servers and/or crashed switches will not cause sockets to be closed. Therefore hung members will not be suspected and network partitions due to switch failures will not be detected. A solution to this problem is to use both FD and FD_SOCK failure detection protocols. For more details refer to Failure Detection


    Configuration Example




    Configuration Example

    bind_addrThe NIC on which the ServerSocket should listen on
    bind_interface_strThe interface (NIC) which should be used by this transport
    get_cache_timeoutTimeout for getting socket cache from coordinator. Default is 1000 msec
    idGive the protocol a different ID if needed so we can have multiple instances of it in the same stack
    keep_aliveWhether to use KEEP_ALIVE on the ping socket or not. Default is true
    levelSets the logger level (see javadocs)
    nameGive the protocol a different name if needed so we can have multiple instances of it in the same stack
    num_triesNumber of attempts coordinator is solicited for socket cache until we give up. Default is 3
    sock_conn_timeoutMax time in millis to wait for ping Socket.connect() to return
    start_portStart port for server socket. Default value of 0 picks a random port
    statsDetermines whether to collect statistics (and expose them via JMX). Default is true
    suspect_msg_intervalInterval for broadcasting suspect messages. Default is 5000 msec


    See also Protocol Configuration Common Parameters.



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