//first attempt fails all the time

mongos> show collections
Fri Feb 24 13:59:08 uncaught exception: error: {
"$err" : "could not initialize sharding on connection replicaset_2/node01:27017,node02:27017,node3:27017 :: caused by :: specified a different configdb!",
"code" : 15907
}

//second attempt succeed

mongos> show collections
system.indexes
system.users

Config servers are in sync!