Roll Back the Software to a Previous Version
SUMMARY Junos OS Evolved maintains multiple versions of the software and configuration files on
the primary solid-state drive (SSD) on the Routing Engine (RE). Each time you issue the
request system software add
operational mode command, the previous software
image and configuration is preserved automatically. The last running software image and
corresponding configuration file is the default rollback image. Older images, along with the
configuration present when the older image was running, are preserved as well.
You use the rollback image and configuration preserved by default to revert to a prior image on the same disk as the current image.
After an upgrade or a roll back, if the software is unable to use the current configuration, the RE is often still reachable using the current management interface configuration. If the management interface does not come up, use the console to connect to the device to roll back the software and configuration.
After an upgrade, if the installation fails during early boot, the RE automatically reverts to booting from the secondary SSD, where snapshots are stored. You can then reboot the RE using the snapshot saved on the secondary SSD. You can then roll back the software version, especially if the snapshot version is not a recent-enough version of the software and configuration.
For a dual-RE device, the request system rollback
operational mode command
reverts both REs to the rollback software version. For all devices, the command rolls back
the software version on the FPCs as well.
-
To see which software images are available for rollback, use the
show system software list
operational mode command. -
To roll back to any image with the current configuration (the snapshot configuration),
use the
request system software rollback package-name
operational mode command. -
To roll back to the last running image with its corresponding configuration from when
the software was last running, use the
request system software rollback with-old-snapshot-config
operational mode command. -
To roll back to any image and its corresponding configuration, use the
request system software rollback package-name with-old-snaphot-config
operational mode command.