Configuration question..

B. Cook bcook at poklib.org
Tue Sep 12 16:42:06 UTC 2006


Keith.Neufeld at wichita.edu wrote:
>> . . .
>>
>> The webmin gui doesn't show us the defined hosts we have, and we can't 
>> figure out where/how to add them.. so I started to think that somehow 
>> our config is incorrect..
>>
>> . . .
>>
>> We use hosts in pools, b/c I have one setup for unknown clients and one 
>> for known clients.. and well, in the pools I can't see the defined hosts 
> 
>> that we have in the webmin gui.
> 
> The fact that the host declarations are inside the pool declaration is 
> actually irrelevant to whether they can get a lease from that pool or 
> not--the determination is made (in your configuration) by whether they're 
> known (listed anywhere in the configuration) or unknown.
> 
> To demonstrate that, take the host declaration for ronlapbop [sic] and 
> move it to the 10.0.0.0 "Public Network" section of your configuration, 
> then try to boot it on your 192.168.1.0 subnet.  It'll still get an 
> address from one of your known-host ranges, _not_ from the 192.168.1.20-25 
> range for unknown clients.
> 
> There's been a thread on the mailing list recently about proper placement 
> of host declarations; but the common wisdom is to put them _outside_ of 
> all blocks, in the global scope, UNLESS you specifically want them to use 
> some of the options from their "home" subnet even when they're roaming to 
> other subnets.  [Did I say that about right?]  Putting host declarations 
> inside subnet or pool declarations can lead people to think the hosts are 
> tied to getting addresses only from the subnet or pool (which isn't 
> actually the case), so it's nicer to put them globally and avoid the 
> confusion.
> 
> 
> It may be just the way my browser is displaying the file, but I prefer 
> indenting blocks visually to match their syntactic nesting--so it'd be 
> easier for me to read quickly if e.g. the stuff inside the 10.0.0.65-94 
> pool were indented by another tabstop, and the hosts inside it (if they 
> stay there) indented two tabstops from where they appear now.
> 
> My $.02.
> 

Ok,

Heres what I have done and what I have discovered..

I have a host dilvish in my 192.168.1.0 subnet::pool,
host dilvish		{ hardware ethernet 00:60:97:7b:6d:d8; option routers 
192.168.1.2;}

I move that to the 10.0.0.0 subnet::pool, and remove the routers option..
host dilvish		{ hardware ethernet 00:60:97:7b:6d:d8; }

restart dhcpd, have the win2k box relase and then renew it's IP, it gets 
the same 192.168.1.250 IP but it gets all the things associated w/ the 
10. (I think this is what you were saying would happen.. )

When I comment out the entry (now existing only in the 10 subnet) and 
then restart dhcpd and then have the client renew it gets an ip in the 
192.168.1.22 range.  (I am not sure if you said this would happen.. )

This is understandable.. (sort of) as this host is coming to the dhcpd 
server on the 192.168.1.x subnet, and like you said "..known (listed 
anywhere in the configuration).. ".

What I am looking for is that when hosts come in through the dhcp-relay 
on the router that they get routed to the right subnet and follow the 
correct known/unknown settings that I have provided for them.

And I seem to still have that..


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