[Solved]MAC ID on a multiboot system

Newly installed OpenWrt to a NetgearR7800. My network is part wired, part wifi. Main wired computer multiboots 3 linux OSes and Win10 (seldom used). Whichever OS is booted, the machine ID is the same (of course). I use DHCP generally on the network, but reserve specific IPv4 numbers (static leases) for some of my wired devices including my multiboot box. When reserving an IP, OpenWrt wants a unique MAC ID. The only way to do this (that I can see) is to let one OS have the real MAC ID and another that boots on the same machine have an altered one. For example if the real MAC ID was 22:33:44:55:66:AA, then for another OS booting on that machine, I might custom make it 22:33:44:55:66:BB, and for a third OS 22:33:44:55:66:CC. This seemed to work on my previous router (with Tomato) and it seems to work on OpenWrt. Is there any problem with this? I'm asking because 2 of my linux distros respond to the router and see the network properly, but one seems to intermittently get "lost" ...unable to find other machines on the LAN. Might be something else though.

Sounds like you are describing a fairly normal MAC spoofing situation. Based on what you said, there's no reason that I can think of why it wouldn't work on OpenWrt.

Is it possible that the one distro with problems is having a network driver issue?

Be aware that you should choose certain types of MAC, for example you should set the "locally administered" bit and not choose a broadcast or multicast MAC etc. As long as you choose say a random unicast Mac with the locally admin bit set you should be ok. For example


When reserving an IP you can leave the MAC undefined and just use the Client Name to reserve an IP


All answers are right...just different approaches. @dlakelan's link generates proper MACs. @mbo2o correctly says, it can be left blank...actually choose custom and then delete it to get blank. @dit_dah_dit says my approach was OK and that is right too. Also adds the flaky distro is probably having some other issue...I think so too.

I used mbo2o's solution: left the MAC ID blank. This seemed to work OK

thx all!

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