How to revert to ontap lower ver before cluster setup

[Perf-Stor]

The version of ontap for our newly purchased FAS2750 was ver 9.9.1. We have existing cluster environment (ontap 9.7P18) and would like to downgrade from ontap ver 9.9.1 to 9.7 in order to join that environment.

I have checked and it seems that I need to Revert to ver9.8 once.
The downgrade procedure is described in the published documents only for environments with a cluster configuration, but not for downgrading (upgrading) the node before cluster configuration on new equipment.
Is it necessary to do a cluster setup once?
I would appreciate it if you could tell me the procedure to downgrade the node before cluser setup.

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[AlexDawson]

Since the cluster is new, your best option is to put the ONTAP image onto two USB keys, plug them into the USB ports on the back of each controller, halt both nodes and then connect via serial and choose option 7 - install new software first - from the special boot menu, and then reboot and choose option 9a/9b to wipe and then reinstate partitioning and then option 4 to wipe and restart cluster setup. You will need the license keys for the system from our website to do this.

For brevity I have simplified this somewhat, if you are unfamiliar with the use of the special boot menu or cluster setup, please let us know.

Hope this helps!

[Perf-Stor]

Thank you for your response.

By license, you mean Cluster base license, CIFS license, etc, right?

[AlexDawson · Accepted solution]

That is correct, yes.

[Perf-Stor]

I have an additional question regarding your recent response.
When putting the ONTAP image in the USB key, do I just download the ONTAP image from the support site and copy it to the root path of the USB key?

[AlexDawson]

That's correct!  We have full details at https://kb.netapp.com/Advice_and_Troubleshooting/Data_Storage_Software/ONTAP_OS/Prepare_USB_drive_to_use_in_ONTAP_boot_recovery_procedure - but it must be FAT32 on MBR partitioned devices

[Perf-Stor]

Thanks！😀