Tectia Server for IBM z/OS can use a key created with OpenSSH as the server host key. The key must be configured with the HostKeyFile option in sshd2_config or have the default file names, hostkey and hostkey.pub.

Both RSA and DSA keys with key lengths from 512 (OpenSSH requires at least 768 for DSA keys) to 4096 bits or more are supported.