Change PCI number of NIC port in DL385 G5p

[D.Hindemith]

In ESX the vmnic0 is assigned to the lowest PCI number, vmnic1 to the next higher, and so on.

In my DL385 G5p there are four embedded NIC ports and in my case four ports on the additional NIC adapter.

The lowest PCI number in the DL385 G5p has the embedded NIC on port 3.

Is it anywhere possible to change the PCI numbers to get them according to the port numbers?

[rick jones]

By "PCI number" do you mean the slot/device number, the bus number or the domain number? Where a PCI device would be uniquely identified by the touple of:

Domain:Bus:Device[.Function]

Either way, I believe the PCI addressing is fixed and is something which cannot be changed.

[D.Hindemith]

With PCI Number I mean i.e. in ESX the location. For the embedded port 3 it is PCI 03:00.0. And for the embedded port 1 it is PCI 41:00.0. And this seems to be the reason that the first port used by ESX is the embedded port 3 (in opposite to all my older DL385 and DL585 where it always was port 1)

[Pieter 't Hart]

maybe the DL385 G5 embedded NIC is no PCI but a PCI-e NIC?
you may get it how you want when your additional board also is PCI-e.

suggestion :
install esx without the additional adapter.
after installation has finished add the board and see how esx numbers them.

[D.Hindemith]

Thanks for your hints.

Now I picked out the additional four-port PCIe NIC (using PCI 47:00.0, PCI 47:00.1, PCI 48:00.0, PCI 48.00.1) and re-installed ESX 3.5 Update 4 by default.

Result as before: vmnic0 (PCI 03:00.0) is port 3, vmnic1 (PCI 03:00.1) is port 4, vmnic2 (PCI 41:00.0) is port 1 and vmnic3 (PCI 41:00.1) is port 4.

So back to my origin question: is it possible to change the PCI address? Or is it fixed as Rick Jones already mentioned?

In this case I would say that with the default settings of ESX (and also Linux) the port 3 is the first network port (if I leave everything default during ESX installation) what seems a bit strange for me.

[rick jones · Accepted solution]

The PCI identification cannot be changed, it is set by the firmware. Since the IDs are fixed, getting the interface names to match the stenciled NIC numbers will call for something else.

I have heard tell that contemporary "Linux" kernels can be told to walk the PCI busses in either breadth first or depth first order. This can change the order in which devices are initially discovered. I do not know if ESX has similar capabilities.

Similarly, the "udev" functionality of contemporary Linux can be used to assign interface names based on invariants other than PCI domain:bus:device.function address such as MAC address etc. You might check if ESX has similar functionality.

[D.Hindemith]

Thanks for your help.

Now I leave it as it is with the embedded ports:

vmnic0 and vmnic1 are port 3 and 4.
vmnic2 and vmnic3 are port 1 and 2.

I don't want to change any default settings in the OS.