ECDSA host key for 'XXX' differs from the key for the IP address

之前在使用 ssh時碰到類似以下的問題： 

Warning: the ECDSA host key for 'XXX' differs from the key for the IP address 'XXX'
Offending key for IP in /home/hadoop/.ssh/known_hosts:5
Matching host key in /home/hadoop/.ssh/known_hosts:7
Are you sure you want to continue connecting (yes/no)?

後來想到因為本機曾經連到過叫hdp2的vm, 但後來hdp2這個vm又重新創造過, 

所以其實算是不同的機器, 但在本機的/home/hadoop/.ssh/known_hosts紀錄的是舊的hdp2資訊, 

與現在連線的hdp2衝突,所以每次連線都在問是否要繼續連線.

解決方式：

將/home/hadoop/.ssh/known_hosts刪掉,

重新ssh到hdp2時他就會問你要不要establish, yes後, 

他似乎會在重建一個known_hosts

下次就不會在出現這個warning了 

[Reference] 

http://security.stackexchange.com/questions/10532/ecdsa-keys-changed-ssh-insecure-now