Friday, March 26, 2010

What's my MAC address? OpenBoot PROM edition

Discovering MAC addresses in OpenBoot PROM:

Enter OpenBoot Prom

Method 1: simple result

ok .enet-addr

Method 2: slightly more information

ok .idprom
Format/Type: ... Ethernet: 0 3 ba xx xx xx Date: ... Serial: ... Checksum: ...

Method 3: in-depth result

ok show-devs

Look through results for 'ethernet', 'network' or similar words. There will probably be multiple network devices.

ok cd /pci@1f,0/ethernet@5

You will receive an output of device properties, look for:

local-mac-address 00 03 ba xx xx xx

Repeat as necessary.


  1. Thanks for the info! I've been struggling with getting MAC address from one of my LDom guests. Apparently, the first two methods gave me the same MAC that was in the OpenBoot banner, but that didn't work with my AI server. Only the third method gave me the right answer and everything worked fine.