Different hardware options based on subnet

Simon Hobson dhcp1 at thehobsons.co.uk
Thu Sep 3 13:41:34 UTC 2020

Ricardo Stella <stella at rider.edu> wrote:

> Is the problem that the definition in the global section of the config trumps whatever is defined inside a subnet?

Normally, definitions in a lower scope (e.g. in a subnet) override options made at a higher level (e.g. at the global level). So (for example) you can set your DNS servers globally and override them for specific subnets or pools.

However, class definitions and host definitions are always global even if declared within a lower scope. This is one that can catch people out.
As classes are "special" in this respect, I could imagine there being similar oddities with option inheritance in cases like yours. But I don't recall this particular setup being asked before, and I'm not familiar with implementation details - I guess if you can read code (I assume it's in C) then you could spend the time (possibly a lot of it) working out how this particular scenario works.


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