Salt Master报错:Minion did not return. [No response]

在salt master端执行salt '*' test.ping时，某一节点出现如下报错：
Minion did not return. [No response]

登陆到这一节点查看minion的日志，发现如下的问题

$ tail -f /var/log/salt/minion
The master may need to be updated if it is a version of Salt lower than 2015.5.3, or
If you are confident that you are connecting to a valid Salt Master, then remove the master public key and restart the Salt Minion.
The master public key can be found at:
/etc/salt/pki/minion/minion_master.pub
2015-11-23 23:30:02,645 [salt.crypt                               ][ERROR   ][3530] The Salt Master has cached the public key for this node, this salt minion will wait for 10 seconds before attempting to re-authenticate
2015-11-23 23:30:05,108 [salt.crypt                               ][ERROR   ][3586] The Salt Master has cached the public key for this node, this salt minion will wait for 10 seconds before attempting to re-authenticate
2015-11-23 23:30:15,136 [salt.crypt                               ][ERROR   ][3586] The Salt Master has cached the public key for this node, this salt minion will wait for 10 seconds before attempting to re-authenticate

大概的意思就是，minion端拿到的key与master端的不符，验证无法通过。
解决方法是删除minion端的key，再重新与master进行连接和认证。

minion

$ cat pki/minion/minion_master.pub 
-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAtzq0AjuyQsVEgsx692GN
... ...
7fbuudp4yu5vcYcqksKIFcm0J3E+OR+rx/NUIHt0ZL8HLxcSn4Si/S6dVp/vE7Oc
swIDAQAB
-----END PUBLIC KEY-----
[root@localhost salt]# rm -fr pki/minion/minion_master.pub

[root@localhost salt]# service salt-minion restart
Stopping salt-minion daemon:                               [  OK  ]
Starting salt-minion daemon:                               [  OK  ]

master

salt-key -A

minion

$ cat pki/minion/minion_master.pub 
-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAy46TJvK9BUqjvaYzmt5Q
... ...
ADw0hU6B/A1kRBeUbb6Fy+HljiSjD3O+mhoK7RE8rCnvJCHfuZSX/qMtLEyoh0vN
tQIDAQAB
-----END PUBLIC KEY-----

至此，master与minion端的通信正常。