Discussion

Solution
Use the following command to commit the configuration changes provisionally:
[edit]
aviva@router1# commit confirmed
commit confirmed will be automatically rolled back in 10 minutes unless confirmed
commit complete
To make the provisional activation permanent, issue the following command:
[edit]
aviva@router1# commit
commit complete
Discussion
When you need to verify that a new or modified configuration is working properly—
and especially if the changes might lock you out of the router—you can provisionally
commit it using the commit confirmed command.
By default, the commit confirmed command activates the configuration for 10 minutes.
Within this time, you must explicitly confirm that the configuration is
acceptable—either by issuing another commit command or by entering the commit
check command—to make the provisional activation permanent. If you do not, the
router loads and activates the previous configuration when 10 minutes have passed.
You have to keep track of the time yourself, because the CLI doesn’t warn you when
it is expiring. The CLI displays a message if you do not confirm the commit when
returning to the previous configuration:
Broadcast Message from root@router1
(no tty) at 15:05 PDT...
Commit was not confirmed; automatic rollback complete.
When working on a production router, if you are concerned that the change you are
making might not go as expected, specify an interval of less than 10 minutes. If you
are quite worried, one minute might be as long as you want to wait:
[edit]
aviva@router1# commit confirmed 1
commit confirmed will be automatically rolled back in 1 minutes unless confirmed
commit complete
1.17 Loading a Previous Router Configuration
Problem
You need to undo the active router configuration and return to a previous configuration.
40 | Chapter 1: Router Configuration and File Management
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