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About linux : nvmet-over-tcp—random-negative-namespace

Question Detail

I’m running nvmet-tcp on a Linux server. I’m trying to pass-thru an nvme device from server to the client. And it’s actually working alright. First, I would load the nvmet and nvmet-tcp on the server

modprobe nvmet
modprobe nvmet-tcp

Then I would create a subsuystem in

cd /sys/kernel/config/nvmet/subsystems
mkdir test

and set all the params. After that, I would go to the namespaces folder in /sys/kernel/config/nvmet/subsystems/test/nvmet

cd test/namespaces
mkdir 1
mkdir 2
mkdir 3

Subsequently, standard config

echo -n /dev/sda1 > 1/device_path
echo -n /dev/sda2 > 2/device_path
echo -n /dev/sda3 > 3/device_path

And enable all of those:

echo -n 1 > 1/enabled
echo -n 1 > 2/enabled
echo -n 1 > 3/enabled

After—activate a port (after proper configuration)

cd /sys/kernel/config/nvmet/ports/1/subsystems/
ln -s  ../../../subsystems/test .

That would fire up the port, and it will work just fine. On a host machine, I would connect with:

nvme connect -t tcp -n test -a 10.10.1.42 -s 4420

The only problem is that when I’m listing namespaces I’m getting an extra “-1” namespace.

nvme list
Node             SN                   Model                                    Namespace Usage                      Format           FW Rev  
---------------- -------------------- ---------------------------------------- --------- -------------------------- ---------------- --------
/dev/nvme0n1     76b9b4aeef600ece     Linux                                    -1          0.00   B /   0.00   B      1   B +  0 B   5.13.0-2
/dev/nvme0n2     76b9b4aeef600ece     Linux                                    1           2.00  GB /   2.00  GB    512   B +  0 B   5.13.0-2
/dev/nvme0n3     76b9b4aeef600ece     Linux                                    2           2.00  GB /   2.00  GB    512   B +  0 B   5.13.0-2
/dev/nvme0n4     76b9b4aeef600ece     Linux                                    3           2.00  GB /   2.00  GB    512   B +  0 B   5.13.0-2

In fact, everything work so great that I’m able to create a new namespace on the fly and the host machine would see it and mount it automatically as a separate disk. But I can’t figure out how to debug/handle the -1 disk that is mounted first in there.

Could anyone please advise?

Question Answer

No answer for now.

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