In some rare conditions, a Junos-based device may become unresponsive for configuration or other operations after executing the command "commit confirmed x" twice.
After executing the CLI command commit confirmed 5 , if the command is still executing as per the set timer value (5 minutes, in this example), and the user sends another “commit confirm” command (during the time slot between the timeout of 5 minutes and the auto-rollback operation), it causes the commit to lock and impacts the operation.
commit confirmed 5
Example:
The user enters the commit confirmed 5 command. The MGD process is undergoing a commit. Then at the same time, the user enters another MGD session ( commit confirmed x ).
commit confirmed x
The following message is logged as part of the second commit but the first commit has not completed:
router-re0 mgd[71402]: UI_CFG_AUDIT_OTHER: User 'root‘ override:/var/run//changes.xml
The following message is logged to show that the rollback action of the first “commit confirmed” started, which eventually is blocked:
router-re0 mgd[74126]: UI_CFG_AUDIT_OTHER: User 'root' override: /config/juniper.conf.unconfirmed.gz
The following message will continue to show that the first "commit confirmed" is still in progress:.
router-re0 mgd[74126]: UI_CFG_AUDIT_OTHER: User 'root' override: /var/run//changes.xml+
Due to a race condition, it enters into a cyclic dependency between two management daemon (MGD) sessions acquiring the db_lock for editing the configuration. Due to this condition, any subsequent user is not be able to enter into the edit mode. The output of the process extensive also shows the MGD process stuck in the lockf state.
The work-around is to kill the MGD process in the lockf state in the UNIX shell. (You must be logged in as root to perform these steps.)
user@router-re1> show system process extensive | grep mgd 2616 root 2 0 13012K 7000K select 0:30 0.00% 0.00% mgd 45570 root 2 0 13068K 9020K lockf 0:02 0.00% 0.00% mgd 45525 root 2 0 14128K 8440K lockf 0:00 0.00% 0.00% mgd 45601 root 2 0 13068K 7712K lockf 0:00 0.00% 0.00% mgd 45624 root 2 0 13052K 7468K select 0:00 0.00% 0.00% mgd
user@router-re1> start shell user root Password: root@router-re1% root@router-re1% kill -9 45570 root@router-re1% kill -9 45525 root@router-re1% kill -9 45601 root@router-re1% exit exit user@router-re1> show system process extensive | grep mgd 45629 root 2 0 13052K 7468K select 0:00 1.00% 0.05% mgd 2616 root 2 0 13012K 7000K select 0:30 0.00% 0.00% mgd
Configuration mode will then be available again.