For configuring SSH to devices through remote access VPN terminating on the ASA ,
apply these commands globally ( if you are accessing the ASA on the VPN Client from the outside interface)
- management-access inside
- ssh (ip pool subnet/mask) inside
For more information, refer to Configuring Secure Shell on Routers and Switches Running Cisco IOS.
Refer to TFTP in order to download the recommended TFTP server.