SSH interactive session can be blocked in deadlock situation if there is some issue with executing command in VAT# console. There can be situation where vpp_api_test could send malformed output or exit/crash. In such situation receiving data from channel.recv and/or channel.recv_stderr must be done properly in order to prevent stall. One of possible solution is to combine stdout/stderr on channel to read from one source. Also proper detection of exit_status of remote console has to be implemented.