Interface Bridge Admin-Mac Generation

RouterOS General
1

I feel like this is already documented somewhere …

I use bridges to act as loopback interfaces. I often use /32 IPv4 addresses and /128 IPv6 addresses on these interfaces. I noticed I had to set an admin MAC address on the interface or add a bridge port for OSPFv3 to treat the interface as valid (showed I, Invalid with admin MAC of all 0’s and no bridge ports).

This is all fine and dandy. My question is are there any suggestions as to what to use for admin MAC addresses to avoid possible conflicts without too much effort?

2

I am always using the mac address of first ethernet member. Or wlan if no ethernets.

3

Thanks Jarda I figured as long as they weren’t duplicate Macs within a switch chip that doesn’t support a per VLAN MAC table I was good as the MAC only has to be unique on the segment.

4

You can use these MAC’s: 00:00:5E:80:00:00 ~ 00:00:5E:FF:FF:FF
Which is declared as reserved Mac Address by IANA for such cases.

Src: https://wiki.mikrotik.com/wiki/Manual:Interface/EoIP#Notes

5

Thank you! That was the list I was thinking of. I wasn’t expecting it to be in the EoIP pages.

6

Thank you to Normunds @ MikroTik for fixing per post reputation for all registered users.