FAS3020 cannot run ontap 8, but FAS3210 can run ontap 7.
You can downgrade the FAS3120 with "priv set diag; revert_to 7.3" (note: you must delete all snapshots and stop fileservice, but revert_to command will tell you). Then you can head-swap and update to ontap 8.
If the FAS3210 came without harddisk you are lost and would need to netboot. Have an experienced netapp technician do so.
The FAS3210 will use the ontap 8 it was delivered with. It will use the basic configuration of your old machine tho, so you only have a partial upgraded system which is prone to produce even more errors.
Upgrade FAS3020 to latest 7 release, head swap, and do a proper software install <8.tgz>; download afterwards, should work.
Follow the following steps for upgrading FAS 3020 to FAS 3120 also suggest that you note down the system ID and the serial numbers.
1 Triigger Latest Autosupport
2 Open a case with NetApp Global Support before head Swap
3 Lable the heads, shelves and cables before the upgrade. Perform a basic health check of the filers. Vol status -f, sysconfig -a, environment chassis status,etc. Make a copy of /etc of both the filers on your local drives.
4 Make note of qtrees, cifs shares(cifsconfig_shares.cfg), home directories(cifs_homedir.cfg) and snapmirror & snapvault relationships/schedules(snapmirror.conf, snapvault.conf). Also, make a copy of the related files to your pc.[Also, make sure you have completed the necessary backups to tape.] I assume that you have snapmirror and snapvault licenses on the 3020 controller if you dont have it then no need to check snapmirror and snapvault
5 Run 'disk show -v' and note down all the disk serial numbers along with the owner information.( V.V. Imp)
6 Perform a Snapmirror & Snapvault update on all the volumes & qtrees respectively. if you have the licenses for the same.
7 Disable cluster: filer> cf disable.
8 Do CIFS terminate. Also, disable snapmirror and snapvault using commands "snapmirror off" and "snapvault off" respectively.
9 Check if the FAS 3020 uses hardware base disk ownership or software base disk ownership if it uses hardware base dick ownership then reassign disk to software base disk ownership since it is good to have softwarebase disk ownership for safer side. to reassign disk to software base disk ownership boot the controller to maintenance mode and enter the following command disk upgrade_ownership the disk upgrade_ownership converts the system to software base ownership then exist the maintenance mode by giving command halt and boot DATA ONTAP by giving the command on loader prompt boot_ontap
10 after the filer boots perfomr the health check
11 Create a new volume called temproot on FAS 3020 this will be the new temparory root volume
12 Using volcopy, copy the contents of your original root volume, including all subdirectories and their contents to the newly created temp volume, temproot:
vol restrict temproot vol copy -S start /vol/vol0 /vol/temproot vol online temproot 13 Make the temproot volume the root directory: vol options temproot root
14 Do a software install and download on FAS 3020 only if the DOT is not up-to-date.
CAUTION: Do NOT reboot after this step.
15 Halt the current FAS 3020 filer head. Then turn power off. Turn off the power to the disk shelves.
16 Properly ground yourself. Disconnect the cables from the FAS 3020 controllers, remove the controllers from the equipment rack or system cabinet, and then install the FAS 3120 controllers as described in the FAS 3120 Installation and Setup instructions.
17 Cable the FAS 3120 controllers as described in the FAS 3120 Installation and Setup instructions and the Active/Active Configuration Guide.
18 Turn on the disk shelves and wait a full minute for them to initialize and become synchronized.
19 Turn on the FAS 3120 system and boot into maintenance mode view disk ownership on FAS 3120 by entering the command disk show -v The console displays a list of all the disks visible to the system, whether the system owns them or not.
20 Assign the disks on the shelves that you migrated to the FAS 3120 system by entering the following command:disk reassign -s old_sysid -d new_sysid
21 halt the system to exist from the maintenance mode and boot the system to DATA ONTAP ensure that filer are operating correctly and resolve any errors enconter
- FAS3120 does not exist. This is either FAS3210 or FAS3140/3160/3170
- If this is FAS3210 and it was shipped with DOT 8.0.x, FAS3020 needs updating to DOT 8.0.x in step 14. Have you tried whether this update is possible or it will be rejected due to unsupported platform?
Otherwise the idea to create root volume copy is interesting.
kernel is loaded from internal boot device, it is independent of the content of root volume. Root volume is used only store settings, firmware files etc, but not kernel. So it will be running 8.x in this case (assuming FAS3210 actually has 8.x; it could also be ordered and delivered with 7.3).
revert_to alone is not enough; it is necessary to also install 7.3 kernel.
But the question is really good. And let's consider moving from 3020 to 6210, which can NOT run 7.3 at all. Assuming this upgrade is supported, booting 8.x with root volume from 7.x should be possible. Checking upgrade guides, they all assume you can update old head to a version on new head.
I still tend to think it should be possible to just boot 8.x and "update" to have correct root volume content. This always worked with 7G before ...
I havent tried updating 3020 to 8.0.x but yes we had reverted back the OnTAp on 3210 to 7.3.6 but i feel we should be able to upgrade the files in 3020 since we will not be taking reboot after upgrading the OS.