新手求教MongoDB副本集配置问题

本人一共搭建了3个虚拟机，都是以mongod --replSet spock --fork --syslog的方式启动的，启动了一个Mongo shell之后输入如下代码：
> config = {"_id": "spock", "members": [{"_id": 0, "host": "localhost:27017"}, {"_id": 1, "host": "virtual1:27017"}, {"_id": 2, "host": "virtual2:27017"}]};
{
"_id" : "spock",
"members" : [
{
"_id" : 0,
"host" : "localhost:27017"
},
{
"_id" : 1,
"host" : "virtual1:27017"
},
{
"_id" : 2,
"host" : "virtual2:27017"
}
]
}
> rs.initiate(config);
{
"ok" : 0,
"errmsg" : "Either all host names in a replica set configuration must be localhost references, or none must be; found 1 out of 3",
"code" : 93
}
报这个错误，请问这是什么原因？