why use the ssh to start mpss on the remote host hang?

[Xiao_peng_W_]

I am trying to start the mpss service on the remote host, but the ssh could not return when the mpss has been started on the remote host.

    ssh <remote host> service mpss start

Any one has any idea?

[Xiao_peng_W_]

From the output of 'service mpps start' that the mpss has been started successfully. But the ssh command could not return.

 ssh host service mpss start
Starting MPSS Stack: [  OK  ]
mic0: online (mode: linux image: /opt/intel/mic/mnt/lib/firmware/mic/uos.img)
mic1: online (mode: linux image: /opt/intel/mic/mnt/lib/firmware/mic/uos.img

In the process list on the remote host node I saw following process when running the 'ssh <host node> service mpss start'
5     0  3125     1  20   0  64068  1120 poll_s Ss   ?          0:00 /usr/sbin/sshd TERM=linux SSH_USE_STRONG_RNG=0 PATH=/sbin:/usr/sbin:/bin:/usr/bin RUNLEVEL=3 runlevel=3 P
4     0 11663  3125  20   0  95744  3788 poll_s Ss   ?          0:00  \_ sshd: root@notty
4     0 11665 11663  20   0   9284  1304 wait   Ss   ?          0:00      \_ bash -c export NODE=c902f04x35; export LANG=en_US.UTF-8 LC_CTYPE="C" LC_NUMERIC="C" LC_TIME="C" L
0     0 11680 11665  20   0   9548  1500 wait   S    ?          0:00          \_ /bin/sh /sbin/service mpss start LC_PAPER=C LC_ADDRESS=C LC_MONETARY=C NODE=c902f04x35 SHELL=
0     0 11685 11680  20   0 108520  1708 wait   S    ?          0:00              \_ /bin/bash /etc/init.d/mpss start PATH=/sbin:/usr/sbin:/bin:/usr/bin TERM=dumb
0     0 11701 11685  20   0  17460   764 hrtime S    ?          0:00                  \_ micctrl -w TERM=dumb PATH=/sbin:/usr/sbin:/bin:/usr/bin PWD=/ LANG=en_US.UTF-8 SHLVL=

After a while I saw the process of 'service mpss start' on the remote host has been finished. But the process 'sshd: root@notty' still stay there. And I am sure this process is the root cause that xdsh did not return since if killing this process on the remote host, the ssh would return directly on my orinigal node.
5     0  3125     1  20   0  64068  1120 poll_s Ss   ?          0:00 /usr/sbin/sshd TERM=linux SSH_USE_STRONG_RNG=0 PATH=/sbin:/usr/sbin:/bin:/usr/bin RUNLEVEL=3 runlevel=3 P
4     0 11663  3125  20   0  95744  3788 poll_s Ss   ?          0:00  \_ sshd: root@notty

First, I thought the process 'sshd: root@notty' is waiting for child process. But looks there was no child process for it. The daemon mpss which started by 'service mpss start' has been separated from the sshd that the parent process is '1'.
5 S root     11693     1  0  80   0 - 94298 scif_a 10:00 ?        00:00:00 /usr/sbin/mpssd

Any suggestions are appreciated.