Juniper Networks J-Series - Manual (Page 208)

router. To downgrade to an earlier version of software, follow the procedure for
upgrading, using the JUNOS software image labeled with the appropriate release.
To downgrade software with the CLI:
1. Enter the request system software rollback command to return to the previous
JUNOS software version:
user@host> request system software rollback
The previous software version is now ready to become active when you next
reboot the router.
2. Reboot the router:
user@host> request system reboot
The router is now running the previous version of the software.
Configuring Boot Devices
You can configure a boot device to replace the primary boot device on your Services
Router, or to act as a backup boot device. The backup device must have a storage
capacity of at least 256 MB. Use either the J-Web interface or the CLI to take a snapshot
of the configuration currently running on the router, or of the original factory
configuration and a rescue configuration, and save it to an alternate medium.
NOTE: For media redundancy, we recommend that you keep a secondary storage
medium attached to the Services Router and updated at all times.
If the primary storage medium becomes corrupted and no backup medium is in
place, you can recover the primary compact flash from a special JUNOS software
image. You can also configure a boot device to store snapshots of software failures,
for use in troubleshooting.
For information about installing boot devices, see the Getting Started Guide for your
router.
This section contains the following topics:
■ Configuring a Boot Device for Backup with the J-Web Interface on page 186
■ Configuring a Boot Device for Backup with the CLI on page 189
■ Configuring a Boot Device to Receive Software Failure Memory
Snapshots on page 190
Configuring a Boot Device for Backup with the J-Web Interface
You can use the J-Web interface to create a boot device for the Services Router on
an alternate medium, to replace the primary boot device or serve as a backup.
186 ■ Configuring Boot Devices
J-series™ Services Router Administration Guide