There is no SSH server in TRACE32. However you can control TRACE32 remotely via the TRACE32 remote API. See the document "api_remote.pdf" in the PDF folder of your TRACE32 installation.
To launch some scripts or execute some simple commands from a bash shell, you can use the command line tool t32rem from the <t32>/bin/linux folder.
This tool uses the TRACE32 remote API to send TRACE32 commands to open TRACE32 GUIs.
Do the following:
Enable the TRACE32 remote API to add the following two lines to your TRACE32 configuration file (usually "config.t32")
RCL=NETASSIST
PORT=20000
You have to ensure that there is an empty line before and after these lines in your configuration file.
Launch TRACE32 and send a command to it with t32rem like that:
t32rem localhost port=20000 <command>
For <command> you can choose any TRACE32 command like DO file.cmm
to execute your mentioned PRACTICE script.
For more complex remote control of TRACE32 (e.g. from a Python script) you should have a look at the previously mentioned "api_remote.pdf" and the examples at <t32>/demo/api.