Change MAC-address of NIC

[frater]

I have a multi LAN/WAN setup with more than 30 VLANs on a

This pfsense machine is the SPOF (single point of failure) for a small community.
When it goes down I have a spare machine, exactly the same, which can turned on.
Each hour the config of my pfsense is downloaded and I will always have a fresh XML which I can put in the new machine.

Even though I have this machine running, it will take a lot of time before it is actually working.
This, because the NICs have different MAC-addresses.

Furthermore I will get a different WAN IP-address on 1 of the 5 WAN-connections.
Most is more of a nuisance than necessity, but if possible I would like to solve it.

I was thinking about giving these commands as an "earlyshellcmd" in the config.xml

ifconfig em0 ether 02:01:02:03:04:05
ifconfig em1 ether 02:01:02:03:04:05

BTW      In the past I tried to use the MAC-spoof option for my WAN, but somehow it doesn't work when these interfaces are VLANs. At least not with the NIC I was using.

Has anyone tried it before and is it a good idea?

I have put these commands already in my config, but I have no way to test it….

[jimp]

VLAN MACs follow the MAC of their parent interface. Assign the parent interface of the VLANs, set IP type to none, and spoof the MAC there.