about concept "group", "shared-network", and "subnet", thanks.

Chris Buxton chris.p.buxton at gmail.com
Tue Apr 19 19:07:10 UTC 2011

On Apr 19, 2011, at 1:42 AM, Simon Hobson wrote:

> So, inheritance rules go like this, going more specific from left to right, and with more specific option overriding the more general ones :
> global - [shared-network] - subnet - pool
> And for hosts with a host declaration (I think)
> global - [group] - host - [shared-network] - subnet - pool

Don't forget about class statements. You can apply options in a class statement the same way as on a group.

Think of a class as a group in which you identify members not by client ID or MAC address but by some other attribute of the request packet. Or they can be used as a faster-processing version of group and hosts.

I think your inheritance diagram is incorrect. I believe group, class, and host options have more precedence than subnet options.

global - [shared-network] - subnet - [pool] - [group] - [class] - [subclass] - [host]

Or something like that. I haven't checked the source code, though, so that might not be totally accurate. For most configurations, the specific order doesn't matter; it works the way you probably want it to work.

Chris Buxton
BlueCat Networks

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