Client classification based on device name. It is possible?

Алексей Прокопчук alexpro at
Sun Jul 8 21:55:05 UTC 2012

Good time of the day!
06.07.2012 23:00, Simon Hobson пишет:
> Different VLANs are **NOT** a shared network. Specifically, a shared
> network relates to having multiple subnets in the same broadcast domain.
> So and are one shared network (in VLAN 21).
> And and are in a **DIFFERENT** shared
> network (in VLAN 22).
> And so on.

> One other thing you've done that is a common mistake ...
>>  subnet
>>  {
>>    deny unknown-clients;
>>    host m1
>>    {
>>      hardware ethernet 00:01:02:03:04:05;
>>      fixed-address;
>>    }
>>  }
> Now, no matter where they are declared, host statements are global in
> scope. So this host declaration is valid **anywhere** in your network,
> not just in VLAN 21. Where it gets interesting is what happens if you
> plug it into VLAN 22.
> It will (depending on any restrictions applied) get an address from a
> range in VLAN 22 - though in the config snippet you've posted, there
> won't (I don't think) be a dynamic address it's allowed to use.
> Were it to get an address, then it would inherit options from the
> subnet where it's defined - including the router !
> So you could have a device that got (say), but had a
> router of which isn't in the same subnet. We have had at
> least one query here where that was happening and it did take a little
> while to realise why.
Thanks for good explanation, I rewrite config according your
recomendations and all works very well.
Now config looks like this:

 shared-network vlan21
       allow unknown-clients;
     deny unknown-clients;
     host m1
       hardware ethernet 00:01:02:03:04:05;

... and so on for each network device.

Now, server offers IP address from proper pool. In case with host with
fixed-address all works well too.
Thanks again, you really helped me.

With best regards, Alexey Prokopchuk

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