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Sapiens

Member

Registered: 2021-07-05

Posts: 52

Network device naming deviates from naming scheme ...

... hi there.

I just ran into a weird issue that is not clear to me why it is and what to be done about it.
I have several computers with Intel X550-T2 NICs installed that are SR-IOV capable. Meaning each of the dual NICs is able to spawn up to 64 virtual functions (virtual NICs basically) that can be used by virtual machines to access the network as if they had their own NIC each.

The physical NICs are named enp36s0f0 and enp36s0f1 by my computer. I then spawn the virtual functions via a systemd service that includes the following code:

 ExecStart=/usr/bin/bash -c '/usr/bin/echo 16 > /sys/class/net/enp36s0f0/device/sriov_numvfs'
ExecStart=/usr/bin/bash -c '/usr/bin/echo 16 > /sys/class/net/enp36s0f1/device/sriov_numvfs'

Previously this resulted in the virtual functions getting labels like enp36s0f0v0, enp36s0f0v1, enp36s0f0v2 and so on. This kind of naming is correct as far as I understand the naming scheme this is based on. It leaves the s for the slot the f for the interface and just increments v for the virtual function.

Sometime very recently this changed however and now the physical NICs are still labeled enp36s0f0 and enp36s0f1 but the naming for the virtual functions is all over the place enp37s17v4, enp37s18f4v10, enp37s16f1v0 and more. As far as I understand this makes no sense since it is the same interface with the same slot, only the v should increment.

It seems naming is corrected by UDEV rules, but I don't want to hardcore all of them on all computers. I would rather like to know if there is a way to force them into the old scheme.

Thank you all for taking the time to read here.

Last edited by Sapiens (2023-01-07 16:42:51)

rootpeer

Member

Registered: 2019-04-07

Posts: 43

Re: Network device naming deviates from naming scheme ...

... hi there.

I just ran into a weird issue that is not clear to me why it is and what to be done about it.
I have several computers with Intel X550-T2 NICs installed that are SR-IOV capable. Meaning each of the dual NICs is able to spawn up to 64 virtual functions (virtual NICs basically) that can be used by virtual machines to access the network as if they had their own NIC each.

The physical NICs are named enp36s0f0 and enp36s0f1 by my computer. I then spawn the virtual functions via a systemd service that includes the following code:

ExecStart=/usr/bin/bash -c '/usr/bin/echo 16 > /sys/class/net/enp36s0f0/device/sriov_numvfs'
ExecStart=/usr/bin/bash -c '/usr/bin/echo 16 > /sys/class/net/enp36s0f1/device/sriov_numvfs'

Previously this resulted in the virtual functions getting labels like enp36s0f0v0, enp36s0f0v1, enp36s0f0v2 and so on. This kind of naming is correct as far as I understand the naming scheme this is based on. It leaves the s for the slot the f for the interface and just increments v for the virtual function.

Sometime very recently this changed however and now the physical NICs are still labeled enp36s0f0 and enp36s0f1 but the naming for the virtual functions is all over the place enp37s17v4, enp37s18f4v10, enp37s16f1v0 and more. As far as I understand this makes no sense since it is the same interface with the same slot, only the v should increment.

It seems naming is corrected by UDEV rules, but I don't want to hardcore all of them on all computers. I would rather like to know if there is a way to force them into the old scheme.

Thank you all for taking the time to read here.

I have the same issue. Did you find a solution?