Configuration Image Validation is not supported on QFX platforms during upgrade or downgrade.

With Configuration Image Validation the system validates that the existing configuration is compatible with the new image before the actual upgrade or downgrade commences.However due to product design QFX platforms where Routing Engine is running as VM ( virtual machine) , Configuration Image Validation is not supported.

Incase of any configuration compatibility issues between old image and new image, software upgrade will NOT be able to validate the configuration and system may not be able to apply the configuration when system comes up on newer software image after upgrade and traffic may get impacted until configuration is corrected and manually committed.

It is recommended, to test the compatibility of the configuration prior the the software upgrade on a non production QFX device.
 

• Prepare a dedicated non-production QFX device already running newer  software version with factory default configuration.
• Load the upgrade candidate’s configuration into the device and commit
  • ​If commit fails, correct the invalid configuration  and re-apply the configuration until commit is successful.
•  Run ‘test configuration  <configuration path>’   to validate the  configuration of older software version for commit errors and syntax errors on the newer software version device
  • If the "test" fails, correct the invalid configuration and re-run test until all validation passes
  • If the test  succeeds, the candidate configuration could be upgraded

In case of any help, please contact JTAC or open the case in Case Manager.