我想用一台主机和3台奴隶机构建一个hadoop集群。我可以通过像ssh slave1这样的代码ssh到任何奴隶机器，但是在构建集群时我遇到了错误，它一直在问我密码。我输入了正确的，但程序仍然失败。
hadoop@master:~$ start-dfs.sh
17/10/24 13:46:15 WARN hdfs.DFSUtilClient: Namenode for null remains unresolved for ID null. Check your hdfs-site.xml file to ensure namenodes are configured properly.
Starting namenodes on [master]
master: ssh: Could not resolve hostname master: Temporary failure in name resolution
hadoop@slave1's password: hadoop@slave3's password: hadoop@slave2's password:
hadoop@slave3's password: slave3: Permission denied, please try again.
hadoop@slave3's password: slave3: Permission denied, please try again.
hadoop@slave1's password: slave1: Permission denied, please try again.
hadoop@slave2's password: slave2: Permission denied, please try again.
slave1: Permission denied, please try again.
hadoop@slave1's password:
hadoop@slave2's password: slave2: Permission denied, please try again.
slave1: Permission denied (publickey,password).
23571113
slave3: Permission denied (publickey,password).
23571113
slave2: Permission denied (publickey,password).
Starting secondary namenodes [0.0.0.0]
0.0.0.0: starting secondarynamenode, logging to /usr/local/hadoop/logs/hadoop-hadoop-secondarynamemaster.out