Resolved Failed to check SSH Connection to the source Server 'source'

[linuxKurt]

Server operating system version

Ubuntu 22.04

Plesk version and microupdate number

Plesk Obsidian 18.0

This is a continuation of my efforts to migrate from a CentOS 6 server to a Ubuntu 22.04 server. I had this issue before and it was resolved via host provider and a PLESK ticket which I do not have access to. I am working with my Host Provider to try and get that information. I believe the basic issue is that the "target" cannot negotiate a connection with the "source". We are using an ECDSA Key as previously mentioned RSA keys were not working. I think the core issue is that although we have a valid ECDSA key and Public Key, the negotiation is failing. Below is the error message I see when I try to kick off a migration.

 

[Hajime Tanaka]

Have you tried using telnet to ensure your ports 21/22 are open and listen to the firewall?

These errors cause time out or couldn't connect without the port open.

 

[linuxKurt]

Have you tried using telnet to ensure your ports 21/22 are open and listen to the firewall?

These errors cause time out or couldn't connect without the port open.

Thanks, I was able to work thru the above error, but the core issue still exists. I am getting the below error now, unable to negotiate. This is the reason in the past where we went to using ecdsa key, but for some reason, the source server is not able to validate or something like that. The public key is definitely in /root/.ssh on source server

Unable to negotiate with xx.xx.xx.x port 22: no matching host key type found. Their offer: ssh-rsa,ssh-dss

 

[linuxKurt]

This issue is resolved. Using ECDSA key and I am not 100% sure, but I think it was updating the config and sshd_config that did it.

 

[Hajime Tanaka]

This issue is resolved. Using ECDSA key and I am not 100% sure, but I think it was updating the config and sshd_config that did it.

I'm glad to hear that you have solved this issue solution as masked!

 

[ilyalad]

This issue is resolved. Using ECDSA key and I am not 100% sure, but I think it was updating the config and sshd_config that did it.

Thanks a lot for a tipp, generation of ssh key type ECDSA helped me.

ssh-keygen -b256 -t ecdsa -f ~/.ssh/id_ecdsa_key -q -N ""

After adding the key to source host, all worked fine.