conflicting configuration changes to field when do online upgrade from 1.8.0 to 1.8.1

Install couchbase server 1.8.0r-55 on 4 nodes cluster.
Remove node 69
Uninstall couchbase server 1.8.0r-55 and install couchbase server 1.8.1r-769 on node 69
Add node 69 back to cluster.
When rebalance, I see I lot of error in log page like below:

Conflicting configuration changes to field

{node,'ns_1@10.1.2.69', port_servers}

:
[{'_vclock',[{'ns_1@10.1.2.69',{1,63502542885}}]},
{moxi,"c:/Program Files/Couchbase/Server/bin/moxi",
["-Z",

{"port_listen=~B,default_bucket_name=default,downstream_max=1024,downstream_conn_max=4,connect_max_errors=5,connect_retry_interval=30000,connect_timeout=400,auth_timeout=100,cycle=200,downstream_conn_queue_timeout=200,downstream_timeout=5000,wait_queue_timeout=200", [port]},
"-z",
{"url=http://127.0.0.1:~B/pools/default/saslBucketsStreaming",
[{misc,this_node_rest_port,[]}]},
"-p","0","-Y","y","-O","stderr", {"~s",[verbosity]}],
[{env,[{"EVENT_NOSELECT","1"},
{"MOXI_SASL_PLAIN_USR",{"~s",[{ns_moxi_sup,rest_user,[]}]}},
{"MOXI_SASL_PLAIN_PWD",{"~s",[{ns_moxi_sup,rest_pass,[]}]}}]},
use_stdio,exit_status,port_server_send_eol,stderr_to_stdout,stream]},
{memcached,"c:/Program Files/Couchbase/Server/bin/memcached",
["-X",
"c:/Program Files/Couchbase/Server/lib/memcached/stdin_term_handler.so",
"-l", {"0.0.0.0:~B,0.0.0.0:~B:1000",[port,dedicated_port]},
"-E",
"c:/Program Files/Couchbase/Server/lib/memcached/bucket_engine.so",
"-B","binary","-r","-c","10000","-e", {"admin=~s;default_bucket_name=default;auto_create=false", [admin_user]},{"~s",[verbosity]}],
[{env,[{"EVENT_NOSELECT","1"}, {"MEMCACHED_TOP_KEYS","100"},
{"ISASL_PWFILE",{"~s",[{isasl,path}]}}, {"ISASL_DB_CHECK_TIME","1"}]},
use_stdio,stderr_to_stdout,exit_status,port_server_send_eol,
stream]}] and
[{'_vclock',[{'ns_1@10.1.2.69',{1,63502540465}}]},
{moxi,"c:/Program Files/Couchbase/Server/bin/moxi",
["-Z",{"port_listen=~B,default_bucket_name=default,downstream_max=1024,downstream_conn_max=4,connect_max_errors=5,connect_retry_interval=30000,connect_timeout=400,auth_timeout=100,cycle=200,downstream_conn_queue_timeout=200,downstream_timeout=5000,wait_queue_timeout=200", [port]}

,
"-z",
{"url=http://127.0.0.1:~B/pools/default/saslBucketsStreaming",
[

{misc,this_node_rest_port,[]}

]},
"-p","0","-Y","y","-O","stderr",

{"~s",[verbosity]}],
[{env,[{"EVENT_NOSELECT","1"},
{"MOXI_SASL_PLAIN_USR",{"~s",[{ns_moxi_sup,rest_user,[]}]}},
{"MOXI_SASL_PLAIN_PWD",{"~s",[{ns_moxi_sup,rest_pass,[]}]}}]},
use_stdio,exit_status,port_server_send_eol,stderr_to_stdout,stream]},
{memcached,"c:/Program Files/Couchbase/Server/bin/memcached",
["-X",
"c:/Program Files/Couchbase/Server/lib/memcached/stdin_term_handler.so",
"-p", {"~B",[port]},
"-E",
"c:/Program Files/Couchbase/Server/lib/memcached/bucket_engine.so",
"-B","binary","-r","-c","10000","-e", {"admin=~s;default_bucket_name=default;auto_create=false", [admin_user]},{"~s",[verbosity]}

],
[{env,[

{"EVENT_NOSELECT","1"}

,

{"MEMCACHED_TOP_KEYS","100"}

,
{"ISASL_PWFILE",{"~s",[

{isasl,path}

]}},

{"ISASL_DB_CHECK_TIME","1"}

]},
use_stdio,stderr_to_stdout,exit_status,port_server_send_eol,
stream]}], choosing the former, which looks newer.