On Junos and Junos OS Evolved platforms due to the mgd(Management Daemon) process not releasing commit lock, 
CLI users cannot change the configuration. CLI users cannot access configuration mode  in this state. 
There is no service impact due to this issue.

Router terminal reported below error while try to login from master RE with cli command:

labrouter#cli

could not open user interface connection: management daemon not running

Retry connection attempts ? [yes,no] (yes) could not open user interface connection: management daemon not running

Retry connection attempts ? [yes,no] (yes) yes

We recovered MGD after killed mgd PID’s which got stuck in /var/rundb/commit.lck

1. fstat /var/rundb/commit.lck

2. kill -9 <pid-value>

       where <pid-value> is obtained from output of step 1

Example:

We recovered MGD after killed below mgd PID’s.

 fstat /var/run/db/commit.lck

root@exr01:~ # fstat /var/run/db/commit.lck

USER   CMD     PID  FD MOUNT   INUM MODE     SZ|DV R/W NAME

root   mgd    36044  10 /.mount/var 1605134 -rw-r-----    6 rw /var/run/db/commit.lck

root   mgd    36037  17 /.mount/var 1605134 -rw-r-----    6 rw /var/run/db/commit.lck

root   mgd    35027  9 /.mount/var 1605134 -rw-r-----    6 rw /var/run/db/commit.lck