centos7.1804.qcow2云镜像创建的实例使用centos6ssh登录失败，该怎么解决

[WengSir]

使用centos7.1804.qcow2云镜像创建的实例可以使用centos7系统ssh登录，但使用centos6 版本ssh登录始终失败，使用secureCRT等工具登录始终报错，登录不成功，报错信息“ error: Received disconnect from xxxx port 58874:9: The server's host key failed to verify. This could mean that the server you are connected to is impersonating the server it claims to be. A connection could not be established”


这个是我在openstack上新创建的实例，之前没有ssh或者使用CRT等工具连接过该实例，是第一次连接登录该实例，请问这个问题该怎么解决？

[TrevorH]

This is expected behaviour if the server has changed its key. That's an indicator that your server has had its keys replaced by an admin or by a reinstall or by the ip address being reused by a different machine. It's also a possible indicator of a server compromise or someone performing a man-in-the-middle attack and intercepting your data on the way to your intended target.

[WengSir]

This is expected behaviour if the server has changed its key. --->此系统版本是centos7.5.1804 ,使用的是qcow2的云镜像,并没有更改过密钥，这是新安装的系统，通过centos6使用ssh密码登录就会报错，如果实例安装centos7.3版本的系统，不管使用centos6还是使用CRT工具登录都是成功的。

[TrevorH]

Unfortunately the non-English readers of this forum are small in number so you need to post everything in English. I have no idea what the rest of your posts say.

It is your client system that remembers the host key, stored in ~/.ssh/known_hosts so if your newly installed system is on the same ip address that has been previously used then you can expect this message to occur.

[WengSir]

If the question is so simple, I won't post it here, but thank you for your reply anyway

[WengSir]

I have no idea about this problem.please help me .

ssh client version use OpenSSH_5.3p1, OpenSSL 1.0.0-fips, server version is OpenSSH_7.4p1, OpenSSL 1.0.2k-fips.

Error when i use client ssh server, error is " RSA_public_decrypt failed: error:0407006A:rsa routines:RSA_padding_check_PKCS1_type_1:block type is not 01,key_verify failed for server_host_key "

please help