Creating rescue of the current configuration on the Chassis Cluster before proceeding with ISSU

This article is the third article of a series of articles for performing an ISSU (In-Service Software Upgrade).

  1. Load the Junos Software package on the device
  2. Verify the Health of the Cluster (Important step)
  3. Create backup of the current configuration and set the rescue config
  4. Start the In-Service Software Upgrade
  5. Process to follow, in the event of the ISSU process stalling in the middle of the upgrade

This article primarily addresses how to create a rescue configuration of the Chassis Cluster before proceeding with an upgrade process, such as ISSU.

Create backup of the current configuration.

If the current configuration is a good one, save it as RESCUE:

Reason: Precautionary step for ISSU, to make sure that even if active configuration gets wiped out for some reason, the device will always have a rescue config to load from once it boots up.

You can verify the rescue configuration on the device by doing a ‘file list /config/’ to confirm that the file exists.
Then do a

and review the contents.

Further, it is recommended that you have a latest copy of the running configuration stored on a different storage device/server for easy retrieval if required.

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