trouble on launching linux slave with ssh

[Victoria Wei Lei]

I have a Jenkins master in windows, and a slave on Linux server.  I generated ssh public key with PuTTYgen, copied to slave's ~/.ssh/authorized_keys.  Also created credential for ssh username/password by directly using the public key.  But connection always failed with the following error: 

Warning: no key algorithms provided; JENKINS-42959 disabled
[08/22/17 12:02:01] [SSH] Opening SSH connection to ca2-buildsrv:22.
[08/22/17 12:02:01] [SSH] WARNING: No entry currently exists in the Known Hosts file for this host. Connections will be denied until this new host and its associated key is added to the Known Hosts file.
Key exchange was not finished, connection is closed.

can someone help me how to update known_hosts file. 

Thanks

Victoria 

[Victor Martinez]

Hi,

It seems the message is quite descriptive, did you try to add an entry in the known host file? You can follow the below article:

 - https://support.cloudbees.com/hc/en-us/articles/115000073552-Host-Key-Verification-for-SSH-Agents

Cheers

[Victoria Wei Lei]

Hi, Victor, 

No,  I did not read the article before.  I recently created a jenkins' master with latest version to replace my ancient jenkens master.  Apparently there are quite bit changes in the master/slave configurations.  Now the issue is solved by manually adding the key to known host file,  the linux slave can be launched successfully. 

Thank you so much for your reply. 

Cheers

Victoria