Mac address prefix

[markusbernhard]

Hi.
I have one cluster (3-node) and 3 single proxmox servers running alongside (for various reasons).

I figured I'd set mac address prefixes so I won't have any problems with identical mac addresses for different VM:s.

The cluster runs 8.1.3 and the standalone hosts are 7.4.17, 8.0.3 and 7.4.3.

I go to the options under datacenter, and try to change prefix to BC:24:11:1 (from default BC:24:11) on any of the servers or clusters, but it won't let me click "OK" after adding the last 1. Just a red box around the input field. I tried adding 10 and 10: aswell, but the same problem.

On one of the standalone hosts i tried to edit the datacenter.cfg file to:
keyboard: sv
next-id: lower=300
mac_prefix: BC:24:11:2

But when I added a NIC to a VM, it came up with a random mac address anyways.

Am I doing something wrong? The documentation says " For example, add a separate extra hexadecimal to the Proxmox OUI for each cluster, like BC:24:11:0 for the first, BC:24:11:1 for the second, and so on."

 

[spirit]

BC:24:11:1 -> BC:24:11:01

Edit: It seem than can can only define the 3 first hexa number (mac vendor).
I don't remember than it's was limited previously

 

[markusbernhard]

Yeah, thanks, I tried a couple of different combinations with 10, FF and so on, but no joy.

 

[gfngfn256]

I don't even see that the first three hex groups are generated as "BC:24:11" (as defined in Datacenter, Options, MAC address prefix) in my VM's or CT's - I just get completely random mac address.
Strange behavior?

EDIT: Just tried creating new VM and it did get the "BC:24:11" prefix! Really strange why now its working. I know that restoring from backup will use the complete original MAC, but most of my VM's & LXC's were created originally with Proxmox in the past (on a different machine running PVE). Strange?

 

[DragoonAethis]

Same problem here, I need to define a 5-octet prefix but it accepts prefixes up to 3 octets only, can't set more from the UI and setting it in datacenter.cfg just falls back to the default 3-octet value.

 

[oak.h]

Same problem I also have to use a 5-octet prefix in an environment. Is there any solution/workaround?

 

[fabian]

https://lore.proxmox.com/pve-devel/20241115084923.73207-1-m.almalat@proxmox.com/#r