问题描述
出现这个错误的环境描述，重启hadoop伪分布式的时候，出现了每次启动一个进程都需要输入密码，通过第一印象是配置ssh相互信任关系有问题，但是，我以前的 ssh相互信任是可以正常工作的。检查权限等问题，看/.ssh/authorized_keys 的属性，.ssh目录的权限。经过检查，发现这些都是正常的。 没有找到根本原因，直接把.ssh/删除，重新配置信任关系，还是不行。
排查问题
实时查看/var/log/secure 文件内容
[root@hadoop001 ~]# tail -F /var/log/secure
Mar 30 10:15:10 hadoop001 sshd[3248]: pam_unix(sshd:session): session opened for user root by (uid=0)
Mar 30 10:15:22 hadoop001 sshd[3272]: Accepted password for root from 192.168.100.109 port 58716 ssh2
Mar 30 10:15:22 hadoop001 sshd[3272]: pam_unix(sshd:session): session opened for user root by (uid=0)
Mar 30 10:15:22 hadoop001 sshd[3274]: Accepted password for root from 192.168.100.109 port 58718 ssh2
Mar 30 10:15:22 hadoop001 sshd[3274]: pam_unix(sshd:session): session opened for user root by (uid=0)
Mar 30 10:15:32 hadoop001 su: pam_unix(su-l:session): session opened for user hadoop by root(uid=0)
Mar 30 10:15:37 hadoop001 su: pam_unix(su-l:session): session opened for user hadoop by root(uid=0)
Mar 30 10:15:44 hadoop001 su: pam_unix(su-l:session): session opened for user hadoop by root(uid=0)
Mar 30 10:16:01 hadoop001 sshd[3493]: Authentication refused: bad ownership or modes for directory /home/hadoop
Mar 30 10:17:10 hadoop001 su: pam_unix(su-l:session): session closed for user hadoop
Mar 30 10:17:52 hadoop001 sshd[3493]: Failed password for hadoop from 192.168.100.111 port 51319 ssh2
Mar 30 10:17:53 hadoop001 sshd[3493]: Failed password for hadoop from 192.168.100.111 port 51319 ssh2
Mar 30 10:17:53 hadoop001 sshd[3494]: Connection closed by 192.168.100.111
Mar 30 10:17:53 hadoop001 sshd[3529]: Authentication refused: bad ownership or modes for directory /home/hadoop
Mar 30 10:17:54 hadoop001 sshd[3529]: Failed password for hadoop from 192.168.100.111 port 51320 ssh2
Mar 30 10:17:54 hadoop001 sshd[3529]: Failed password for hadoop from 192.168.100.111 port 51320 ssh2
Mar 30 10:17:54 hadoop001 sshd[3530]: Connection closed by 192.168.100.111
Mar 30 10:17:56 hadoop001 sshd[3590]: Authentication refused: bad ownership or modes for directory /home/hadoop
Mar 30 10:17:57 hadoop001 sshd[3590]: Failed password for hadoop from 127.0.0.1 port 48546 ssh2
Mar 30 10:17:58 hadoop001 sshd[3590]: Failed password for hadoop from 127.0.0.1 port 48546 ssh2
Mar 30 10:17:58 hadoop001 sshd[3591]: Connection closed by 127.0.0.1
Mar 30 10:19:59 hadoop001 sshd[3672]: Authentication refused: bad ownership or modes for directory /home/hadoop
Mar 30 10:20:44 hadoop001 sshd[3673]: Connection closed by ::1
找到问题的原因：
Mar 30 10:16:01 hadoop001 sshd[3493]: Authentication refused: bad ownership or modes for directory /home/hadoop
说明/home/hadoop权限有问题，但是检查过了 /.ssh/authorized_keys文件的属性，以及.ssh文件属性 是不是权限过大。.ssh目录的权限必须是700，同时/.ssh/authorized_keys的权限必须设置成600：
执行下面命令
chmod g-w /home/hadoop
验证
[hadoop@hadoop001 ~]$ start-all.sh
This script is Deprecated. Instead use start-dfs.sh and start-yarn.sh
Starting namenodes on [hadoop001]
hadoop001: starting namenode, logging to /home/hadoop/app/hadoop-2.6.0-cdh5.7.0/logs/hadoop-hadoop-namenode-hadoop001.out
hadoop001: starting datanode, logging to /home/hadoop/app/hadoop-2.6.0-cdh5.7.0/logs/hadoop-hadoop-datanode-hadoop001.out
Starting secondary namenodes [0.0.0.0]
0.0.0.0: starting secondarynamenode, logging to /home/hadoop/app/hadoop-2.6.0-cdh5.7.0/logs/hadoop-hadoop-secondarynamenode-hadoop001.out
starting yarn daemons
starting resourcemanager, logging to /home/hadoop/app/hadoop-2.6.0-cdh5.7.0/logs/yarn-hadoop-resourcemanager-hadoop001.out
hadoop001: starting nodemanager, logging to /home/hadoop/app/hadoop-2.6.0-cdh5.7.0/logs/yarn-hadoop-nodemanager-hadoop001.out
[hadoop@hadoop001 ~]$ jps
5220 NameNode
5524 SecondaryNameNode
5351 DataNode
5898 Jps
5789 NodeManager
5678 ResourceManager
[hadoop@hadoop001 ~]$
集群可以正常启动了。不建议修改修改/etc/ssh/sshd_config文件, 把密码认证关闭, 将认证改为 passwordAuthentication no
重启下sshd。
service sshd restart;
参考博文 参考博文
