We are planning to use Apache Mina SSHd - ssh client in our product. I need to identify if it supports ssh2 protocol. I checked various resources thoroughly but couldn't able to find information around it. Could you please confirm if it supports ssh2 and how to use/ configure it.
Apache MINA SSHD implements version 2 of the SSH protocol. Version 1 is obsolete and no longer considered secure, and almost nobody uses it anymore. The RFCs it links to in the README on GitHub all cover version 2 of the protocol.
Note that because the library supports a large number of cryptographic algorithms, many of which are no longer secure, you should be careful if you are using settings other than the defaults (which, except for the use of the ssh-rsa signature algorithm, should be secure).
If you're looking for some basic setup documentation for a simple client, the README has a link to some documentation for that as well.