Nodes can't join with socat Address already in use

2017-11-14 16:11:29 140304279660288 [Note] WSREP: Member 0.0 (Galera_Node_02) requested state transfer from '*any*'. Selected 1.0 (Galera_Node_01)(SYNCED) as donor.

2017-11-14 16:11:29 140304279660288 [Note] WSREP: Shifting PRIMARY -> JOINER (TO: 786790589)

2017-11-14 16:11:29 140322124806912 [Note] WSREP: Requesting state transfer: success, donor: 1

2017-11-14 16:11:29 140322124806912 [Note] WSREP: GCache history reset: old(00000000-0000-0000-0000-000000000000:0) -> new(709f570f-c7d5-11e7-b709-e25129d5bf65:13)

WSREP_SST: [INFO] Evaluating timeout -k 110 100 socat -u TCP-LISTEN:4444,reuseaddr stdio | xbstream -x; RC=( ${PIPESTATUS[@]} ) (20171114 16:11:29.639)

2017/11/14 16:11:29 socat[26364] E bind(6, {AF=2 0.0.0.0:4444}, 16): Address already in use

WSREP_SST: [ERROR] Error while getting data from donor node:  exit codes: 1 0 (20171114 16:11:29.645)

WSREP_SST: [ERROR] Cleanup after exit with status:32 (20171114 16:11:29.647)

2017-11-14 16:11:29 140304250304256 [ERROR] WSREP: Process completed with error: wsrep_sst_xtrabackup-v2 --role 'joiner' --address '10.30.2.88' --datadir '/mnt/data/mysql/'   --parent '26044' --binlog 'mysqld-bin' : 32 (Broken pipe)

2017-11-14 16:11:29 140304250304256 [ERROR] WSREP: Failed to read uuid:seqno and wsrep_gtid_domain_id from joiner script.

2017-11-14 16:11:29 140322125121792 [ERROR] WSREP: SST failed: 32 (Broken pipe)

2017-11-14 16:11:29 140322125121792 [ERROR] Aborting

}

    err_ = posix_spawnattr_setflags (&attr, POSIX_SPAWN_SETSIGDEF  |

                                            POSIX_SPAWN_SETSIGMASK |

            /* start a new process group */ POSIX_SPAWN_SETPGROUP  |

                                            POSIX_SPAWN_USEVFORK);

    if (err_)

    {