udev SR not working after upgrade to XCP-ng 8.3

[n-buck]

Hi

After updating to 8.3, my SR did not work anymore.
I have created it like this:

mkdir /srv/NasDrives

ln -s /dev/sda2 /srv/NasDrives/sda

xe sr-create name-label="My Nas Storage" name-description="Nas Storage" type=udev content-type=disk device-config:location=/srv/NasDrives


xe sr-scan uuid=id

This results in disks with an unrecognized bus type and 0B size.
I am therefore not able to assign this sr to a vm.

Recreating the SR in a similar manor did not help as well.

[stormi]

Hi, and sorry for the late reply.

Has the situation evolved in the last two weeks?

Pinging @Wescoeur and @Nambrok for insight regarding the use of the udev driver.

[stormi]

And pinging @benjamreis regarding pass-through.

[Nambrok]

The udev sm driver is not PCI passthrough, it makes tapdisk directly show the block device through a PV device to the VM. I will take a look to see if there is any changes in 8.3.

[n-buck]

@stormi thank you for the reply.
The situation has not changed (downgraded to 8.2 again).

How would I test this again, is there a patch released, or would I install again from the iso, then update with yum?

[stormi]

No, no patch released that would address this kind of issue. If you can reproduce on a test host, or find a way for us to reproduce, we can try to find the cause.

[n-buck]

Hello Stormi,
Sorry for the late reply.

Since this is my only set-up and I did not have the storage to backup my data, I was somewhat afraid to test it further on this system.

What I did:

1. Run XCP-NG 8.2.1
2. Create a new Storage-Repository:
   2.1 mkdir /srv/NasDrives
   2.2 xe sr-create name-label="My Nas Storage" name-description="Nas Storage" type=udev content-type=disk device-config:location=/srv/NasDrives
   2.3 ln -s /dev/sda2 /srv/NasDrives/sda ...
   2.4 xe sr-scan uuid=664fb621-a084-8c9a-9858-1041fe5f5a67
3. Assign it to a VM
4. Update to XCP-NG 8.3
   4.1 The Storage-Repository has no drives.
   4.2 Recreating a Storage Repository as described in step 2 did not work either
5. Restore XCP-NG 8.2.1

Since this is also not a supported way to pass the drives to TrueNas, I am in the process to upgrade my system to passing the disks with a HBA.

I hope this is of any help, and thank you for an amazing product!

[jeremfg]

I've just faced this exact issue. I've already commented here also.

My use case is a server that doesn't support IOMMU.

By the sound of it, I should be able to get it working if I install 8.2.1 instead, which would be an acceptable workaround for me. All my other nodes are still running 8.2.1 anyway, this was my first foray into 8.3. I'll test out the downgrade in a few days.

[stormi]

Using XCP-ng 8.2.1 is a temporary solution, but it will only last while XCP-ng 8.2.1 is supported (well, you can continue to use it after it's EOL, but without security fixes).

The udev sm driver is not PCI passthrough, it makes tapdisk directly show the block device through a PV device to the VM. I will take a look to see if there is any changes in 8.3.

@Nambrok Did you reach a conclusion regarding this issue?

[Nambrok]

@stormi Sorry, I haven't had time to look yet. I will be investigating when I have time.