SSH test: Protocol error. Can not agree hostkey

sneader · Post by **sneader** » Thu Mar 31, 2016 7:30 am

I am using HostMon version 10.10.

I turned up a new server, my first CentOS 7 server. I copied a working test from one of my CentOS 6 servers and created a Connection in Connection Manager, with the proper username and password.

When the test runs, I get a reply of "Protocol error. Can not agree hostkey". I only see one or two mentions of this problem in the support forums, and I am led to believe it is some incompatibility with ciphers. Unfortunately, the forum posts were not informative enough to help me with troubleshooting and resolving this problem.

Any help would be greatly appreciated.

KS-Soft · Post by **KS-Soft** » Thu Mar 31, 2016 8:06 am

We plan to improve SSH test in version 10.14 or 10.16..
What ciphers and key exchange enabled on the server?

Can you enable some of the following ciphers
3des-cbc,blowfish-cbc,aes256-cbc,aes192-cbc,aes128-cbc
Key exchange: diffie-hellman-group1-sha1

Regards
Alex

sneader · Post by **sneader** » Thu Mar 31, 2016 5:21 pm

Hi Alex.

I found this article which seems to explain why I am just seeing this problem on CentOS 7:

http://www.jbytechnologies.com/linux/ss ... a-key.html

I will try the suggested fix, and then remove the fix after HostMon improves the SSH test.

- Scott

sneader · Post by **sneader** » Thu Mar 31, 2016 6:18 pm

I can confirm that the dsa key fix in the link above solves the problem for now.

If you would be so kind as to let me know when even a beta version with the ssh fix is available, I would be more than glad to test it out!

- Scott