Important Features of the Dual-Root Partitioning Scheme

The dual-root partitioning scheme has the following important features:

• The primary and backup copies of Junos OS images reside in separate partitions. The partition containing the backup copy is mounted only when required. Where as with the single-root partitioning scheme, there is one root partition that contains both the primary and the backup Junos OS images.
• The request system software add command for a Junos OS package erases the contents of the other root partition. The contents of the other root partition will not be valid unless software installation is completed successfully.
• The add-on packages like jais or jfirmware should be reinstalled as required after a new Junos OS image is installed.
• The request system software rollback CLI command does not delete the current Junos OS image. It is possible to switch back to the image by issuing the rollback command again.
• The request system software delete-backup and request system software validate CLI commands do not take any action.