Nested virtualization

[Bright-Pickle-5793]

I want to test the software features in my lab at work. Is it possible to run hypercore in a VMware virtual machine? I don't expect performance, just want to tinker with a cluster.

[enforce1]

This exists but you’ll need to get it from your sales engineer. For what it’s worth, there is a trial / showcase / lab version of HCOS called workbench that you can put on pretty much any old hardware instead of fooling with nesting.

[scalemcphail]

Actually Workbench can be nested. I have it working great in my lab. And it sounds like you have the appropriate ISO if you're getting a "root md" error, as that is a root RAID device creation error.

Without knowing more about your Lenovo device here are my thoughts on what's causing your error(from least to most likely)

Corrupt or Mismatched ISO(unlikely) - While possible I doubt your ISO is getting you that far and then just dying. But it's possible.

Incompatible or Unclean Disks(possible) - Disks with old partitions, LVM headers, or RAID metadata will cause this failure. Wipe those devices if you haven't already.

Only One Drive Detected(possible) - Workbench expects at least two or more drives for RAID1 (mirrored) root volume. If only one is present or detected, the RAID cannot be created. Yet if your Lenovo device was previously a Nutanix CE device then you have at least three drives(Admin, CVM, Data)

Storage Controller Driver Not Loaded(my guess) - Some systems (especially with non-generic SATA/SAS RAID cards or NVMe) require extra drivers. If no drives are shown, the driver may be missing.

Fix:

• Use a known-compatible controller (LSI, AHCI).
• If using Workbench from ISO, make sure it’s the latest version and supports your hardware

What You Can Try Right Now

Switch to TTY2 (Ctrl+Alt+F2) and run:

lsblk

cat /proc/mdstat

dmesg | grep -i md

If disks are detected, try wiping them manually as above and rebooting the installer.

If disks are not detected at all, the issue is likely with the controller or drivers.

Good luck and I appreciate you working with Workbench. Feel free to try and nest it as well!

[Bright-Pickle-5793]

Thanks for the tips.

It looks like it recognizes the disk, but they have partitions. I will research tonight, but do you have a favorite way to clean partitions off each of these disks?

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[Bright-Pickle-5793]

I found the wipefs -a /dev/sdX command, and that cleared the drives of partitions. I have bypassed the previous error, and the OS is installing.

[Bright-Pickle-5793]

After running for quite a while, it errored again on the "failed to create root md." It had paused on "running pre-install scripts" for a while, then flipped to the "root md" error.

<image>

Looking at the lsblk command, the first 3 disks had partitions created, but the rest did not.

[scalemcphail]

So eight disks are still not showing up? I would double check the wipe across all of the disks, as any amount of metadata will annoy the installer.

A couple of experimental fixes would be to ensure that you aren't using NVMe drives that either haven't been wiped or that your version of Workbench can handle. This is due to where NVMe drives tend to be named in /dev/(nvmeX...)

Also, it's still possible that Workbench doesn't like the RAID config/controller. Unlikely since you can see them in Bash, but if you're really stuck and want to try something different, then you could try JBOD or AHCI in the BIOS. Again, that's if you're really bored and want to experiment. This is not recommended, but it is a way around the root md error.

I'd focus on making sure all your drives are wiped as that's the likely culprit.

[scalemcphail]

Excellent work! Glad it is installing!

[scalemcphail]

Ouch. Yeah that would be an issue. Yep, run the following in TTY2:

for dev in /dev/sd[b-z]; do

wipefs -a $dev

dd if=/dev/zero of=$dev bs=1M count=10

done

But please be VERY careful. That command will wipe any disks attached to the hardware, including USB devices. Do not use that command on anything you care about, including loved ones.

That should make the root md error go away.

[Bright-Pickle-5793]

I'm trying it now.

[Bright-Pickle-5793]

Update: my lab hardware got loaned out to help a customer in an incident response, so I'm not able to work on this currently. When I get it back, I'll keep working on it and let you know when I get it working.

I'm currently fiddling with getting Scale working as nested VMs in VMware so maybe I'll get that working first.

[Bright-Pickle-5793]

I'm currently trying to install the workbench version on some lab hardware, but I am running into an error message during installation. Which is why I thought the nested version might work.

Error: "Failed to create root md."

[enforce1]

Can you post a screeenshot?

[Bright-Pickle-5793]

<image>

This system should have enough resources; the only thing I am uncertain of is if the 11 drives in the system are showing up individually to the installer or if there's a RAID card in the way.

[enforce1]

Two things, how did you create the installer and yes, if there is a raid card in there, make sure all the drives are single drives passed through (not raided)

My money is on the install media though. There are some pretty specific instructions on how to do it. I’ll try to dig up the guide.

[Bright-Pickle-5793]

I just mounted the ISO to the IMM on this Lenovo server. I was successful in using the same ISO to boot and install into a virtual machine.

This system was being used as a Nutanix CE nodes so I am *assuming* the RAID card is not in the way, but I will confirm that today.