[INFO] smt1.TestItems.StartStationTest_smt1 ssh.py:330 2016-09-27 09:51:57.211 start monitoring control master
[INFO] smt1.TestItems.StartStationTest_smt1 ssh.py:377 2016-09-27 09:51:57.215 start monitoring control master until 3835 terminates
Master running (pid=30492)
[INFO] smt1.TestItems.StartStationTest_smt1 ssh.py:366 2016-09-27 09:51:58.240 loss connection, stopping control master
mux_client_request_session: read from master failed: Broken pipe                                                                                                                                                                                                                
Exit request sent.
ssh: connect to host 10.0.1.3 port 22: Connection timed out
[WARNING] smt1.TestItems.StartStationTest_smt1 board.py:352 2016-09-27 09:51:59.259 returned 255, try again (1)
[INFO] smt1.TestItems.StartStationTest_smt1 ssh.py:377 2016-09-27 09:51:59.270 start monitoring control master until 3852 terminates
Control socket connect(/tmp/.ssh-root@10.0.1.3:22): No such file or directory
[INFO] smt1.TestItems.StartStationTest_smt1 ssh.py:362 2016-09-27 09:51:59.283 control master is not running, skipped
ssh: connect to host 10.0.1.3 port 22: Connection timed out
[WARNING] smt1.TestItems.StartStationTest_smt1 board.py:352 2016-09-27 09:52:00.279 returned 255, try again (2)
[INFO] smt1.TestItems.StartStationTest_smt1 ssh.py:377 2016-09-27 09:52:00.289 start monitoring control master until 3855 terminates
Control socket connect(/tmp/.ssh-root@10.0.1.3:22): No such file or directory
[INFO] smt1.TestItems.StartStationTest_smt1 ssh.py:362 2016-09-27 09:52:00.302 control master is not running, skipped
ssh: connect to host 10.0.1.3 port 22: Connection timed out


When we tried to kill control master, it showed an error message:
mux_client_request_session: read from master failed: Broken pipe

And we cannot connect to device any more (control master not restarted).