How to revert a new head's flash from 8.0.2 to 7.3.5 without having a shelf attached to it?

[SVILLARDI]

I have a FAS3140 being replaced by a new FAS3240. The problem I have is the new head was ordered with 8.0.2 but we want to stay on our existing 7.3.5. How can I revert the software on the 3240's flash card without having any shelves attached to it. I don't want to hook up our current shelfs because then the raid labels will get upgraded to 8.x when we turn on the new head and its a pain to fix. Any one have an suggestions?

[franciskim]

This can be done without a shelf attached.

With no shelves attached, interrupt the FAS3240 boot with Ctrl-C to get to the special menu.  You should see something like the following:

Please choose one of the following:

(1) Normal Boot.

(2) Boot without /etc/rc.

.

.

.

(7) Install new software first.

.

.

Select option 7 and follow prompts for downloading your desired DOT image.

[SVILLARDI]

I'm aware that option works for upgrading but when trying to go from 8.x to 7.x that method does not seem to work. Complains about the 7.x ontap not being the correct format. Without being able to issue the revert command it doesn't seem option 7 works for 8.x to 7.x

[aborzenkov]

It looks like the only way to do it is to take couple of spares and install 8.0.2 on them and then do revert. You may unplug all other disks (and hook just a single shelf to start with). That does mean longer downtime though.

Have you already contacted support? I bet there should be a possibility - the situation does not look that rare. If you get it done without brute force I appreciate feedback. Thank you!

P.S. someone found a way to connect UFM to commodity PC?

[haenggi]

You can do this using net boot. You just need a HTTP or TFTP Server and the netboot image. Below the link to a document (don't get confused by the name) on support.netapp.com were you find a small how to on page 4.

Replacing a CompactFlash Card in FAS31xx Series Systems Running Software Prior to Data ONTAP 8.0

[aborzenkov]

You are a genius! Seriously.

@SVILLARDI: reassign disks to new FAS3240, do netboot of version 7.3.5 (or whatever version you currently have) and then do download from booted system. Should work. The link is for FAS31xx, but it works exactly the same (for 7G) for FAS32xx as well.

Be sure to do netboot and not allow it to boot from UFM.

[haenggi]

Netboot Saved my a... some months ago, but the other way around. I got a controller delivered with 7.3 for a head swap of an 8.0.2 system.

[SVILLARDI]

Thanks for everyone's suggestions. I will try this in the lab before I perform the work. Thanks guys! I'll let you all know how it goes.

[SVILLARDI]

I tried your advice in lab and it seems to work for the most part, except when booting from the loader prompt it will always try and boot from the 8.0.2 image. I tried setting the environment variable for boot_ontap and boot_primary but it keeps giving me an error syaing invalid parameters. what would the correct syntax be for that.

below is part of my printing screen:

PRIMARY_KERNEL_URL   fat://boot0/X86_ELF/kernel/primary.krn

BACKUP_KERNEL_URL    fat://boot0/backup/X86_ELF/kernel/primary.krn

DIAG_URL             fat://boot0/X86_ELF/diag/diag.krn

GX_DIAG_URL          fat://boot0/X86/diag/kernel

FIRMWARE_URL         fat://boot0/X86_ELF/firmware/SB_XVII/firmware.img

BMC_FIRMWARE_URL     fat://boot0/X86_ELF/firmware/SB_XVII/bmc.img

BIOS_INTERFACE       86C0

BOOT_FLASH           flash0a

update_bmc           bmc flash $BMC_FIRMWARE_URL

GX_PRIMARY_KERNEL_URL fat://boot0/X86/freebsd/image1/kernel

GX_BACKUP_KERNEL_URL fat://boot0/X86/freebsd/image2/kernel

ntap.init.kernelname X86/freebsd/image1/kernel

AUTOBOOT             true

AUTOBOOT_FROM        UPDATE

AUTO_FW_UPDATE       true

BOOTED_FROM          OTHER

boot_ontap           autoboot boot0

boot_primary         setenv BOOTED_FROM PRIMARY; boot -elf $GX_PRIMARY_KERNEL_URL $PRIMARY_KERNEL_URL

boot_backup          setenv BOOTED_FROM BACKUP; boot -elf $GX_BACKUP_KERNEL_URL $BACKUP_KERNEL_URL

netboot              setenv BOOTED_FROM NETWORK; boot -elf

boot_diags           boot -elf $GX_DIAG_URL $DIAG_URL

ldkern               load -elf $GX_PRIMARY_KERNEL_URL $PRIMARY_KERNEL_URL

im assuming i need to remove the references to $GX_PRIMARY_KERNEL_URL and $GX_BACKUP_KERNEL_URL from the boot_primary and boot_backup variables, im just not sure on the syntax.

I tired:

LOADER-B> setenv boot_primary setenv BOOTED_FROM PRIMARY; boot -elf $PRIMARY_KERNEL_URL

Could not overwrite built-in command 'boot_primary': Invalid parameter

but it seems to be incorrect. if i run: boot -elf $PRIMARY_KERNEL_URL by it self it will boot into 7.3.6 just fine. anyone got any ideas?

[aborzenkov]

Did you try set-defaults at loader prompt?

Otherwise could you describe step by step procedure you followed to downgrade kernel (or better, terminal capture for it)?

[haenggi]

I guess I have to add some details in regards to this process. There is a difference between netboot in Ontap 7.X and 8.X.

In 8.x you do the upgrade of the flash card in the process, where in 7.x you just boot with the kernel you need without updating the flash card, which ends like in your test case. That means for your case, you have to apply the following procedure:

- Replace the 3140 with the 3240 and do all the cabling.

- Netboot with 7.3.5 into maintenance mode

- Reassign the disks to the new controller (if you have a dedicated root aggregate, you can start with only those)

- Halt the system

- Netboot again with 7.3.5 and start up the whole system. Now your system runs with 7.3.5 in Memory and 8.0.2 on the flash

- Do a software update wit the 7.3.5 Image which should reside in /etc/software (software update command). With this procedure, the flash card of the FAS3240 gets "downgraded".

- Check the software with the version -b command

- Reboot the system

Hope this helps.

[aborzenkov]

Well … I presumed “download” step had been performed because 7G kernel seems to be present on boot media, just environment variables are skewed. But yes, knowing exact procedure that was followed would help.

[SVILLARDI · Accepted solution]

I also tried the software update method you describe but it still leaves the 8.x code on the flash. If I do a version -b I see the primary 7.3.5 , backup 7.3.5 and a primary 8.0. What I ended up doing was just reformatting the flash to fat16 and net booting to 7.3.5 and performing another download to copy the boot files to the new flash. That seems to work fine, but I'm not sure if there is any consequences from reformatting the flash like I did.

[aborzenkov]

I was about to suggest the same ☺

I do not expect anything bad. Flash is sometimes completely reformatted during normal upgrade as well. Also before advent of UFM, using PC to reformat CF card and copy Data ONTAP binary was more or less sanctioned action.

Thank you for testing and sharing you experience!

[SVILLARDI]

Thanks for all your help guys. I appreciate all the input you have given me. I will mark the responses as answers when I get to a pc.

[haenggi]

Don't think this will have consequences as aborzenkov wrote already before. Had to do this manually too during a "failed" Ontap Upgrade some time ago with CF Card and CF Card Reader connected to my notebook... 🙂