How to change MAC address on RPI-B?

[John W. Kitz]

Reiner,

So when doing so the locally administered MAC address is passed on from
uEnv.txt to the O/S during boot and is then used to override the globally
unique MAC address or does the O/S check both the information found in its
configuration files and what is configured in uEnv.txt before configuring
and activating the network interface(s)? 

Makes me wonder which of the two (i.e. locally administered through uEnv.txt
or locally administered through the O/S) takes precedence.

In addition this might affect configuration decisions when one would want to
configure a device for net booting (at least when browsing through what can
be configured by means of uEnv.txt I believe that was one of the options I
saw) through uEnv.txt?

Jk.