UNIX for Dummies Questions & Answers

Experts,

We are trying to make a key-based authentication from Server A to Server B.
Server A is installed with openshh. Server B runs "Sun_SSH_1.1".
Server A's rsa2 public key has been added into the server B's authorized_keys.
We are sure that permission settings of the files and folders in server A and Server B are correct.
But when we try to establish SFTP connection from Server B to Server A, we are getting the below error (snippet from -vvv mode logs)

debug3: check_host_in_hostfile: filename /home/serverb/.ssh/known_hosts
debug3: check_host_in_hostfile: filename /etc/ssh/ssh_known_hosts
debug3: check_host_in_hostfile: filename /home/serverb/.ssh/known_hosts
debug3: check_host_in_hostfile: filename /etc/ssh/ssh_known_hosts
debug3: check_host_in_hostfile: filename /home/serverb/.ssh/known_hosts
debug3: check_host_in_hostfile: filename /etc/ssh/ssh_known_hosts
debug2: no key of type 0 for host servera.test.com
debug3: check_host_in_hostfile: filename /home/serverb/.ssh/known_hosts2
debug3: check_host_in_hostfile: filename /etc/ssh/ssh_known_hosts2
debug3: check_host_in_hostfile: filename /home/serverb/.ssh/known_hosts
debug3: check_host_in_hostfile: filename /etc/ssh/ssh_known_hosts
debug2: no key of type 2 for host servera.test.com
Host key verification failed.

When connecting ServerB is not prompting for the adding the key of ServerA in known_hosts file of serverB. We are not sure why this happens.
We deleted the known_hosts file from ServerB and tried connecting, but no help

Can you please help on this?

You are using two different versions of OpenSSH. The keys, and key files, are different.

man ssh-keygen

Look at the "-e" and "-i" command line parameters. These parameters convert keys from one version to the other.

HTH