[K12OSN] DHCP and different LTSP distros

[Les Mikesell]

Terrell Prudé Jr. wrote:

> Strictly speaking, you're correct; DHCP relay would also work.  We must
> remember, though, that the person coming behind the original installer
> (quite possibly a schoolteacher) needs to be able to figure it out, too,
> not just gearheads like you and me.  With LTSP, you likely won't have
> Cisco routers at each LTSP segment; the LTSP server itself is doing that
> L3 segmentation.

Yes, but on 2-NIC (or more) servers you'd probably just run separate 
dhcpd's on each server and routers wouldn't be connected.

> Correctly configuring DHCP relay agents on those LTSP
> servers is a bit beyond *most* school tech admins. 

And there wouldn't be much advantage of setting up the relay vs. a local 
dhcpd.

> Therefore, it's typically a lot easier to get your network engineer, i.
> e. someone like me, to pop some ports into a VLAN without questioning it
> than it is to convince me to let someone stand up a second DHCP
> *anything*.  The former, I'll say, "sure, no prob, give me two
> minutes."  The latter...waitasec, we need to talk BIG TIME first.  This
> is to avoid handing out, say, 192.168's on that 10.x.x.x network and
> taking down half the school as a result.

Agreed, you don't want to mix dhcp servers on any subnet, but what I'm 
suggesting is that all routers be configured with the same ip 
helper-address which would rarely if ever need to be changed, and that a 
single server be configured to control all the dhcp assignments for all 
your routed subnets.  In a multi-ltsp server environment, I'd probably 
want to run this service on the box providing LDAP and the home 
directories but any dhcp server should work.

-- 
   Les Mikesell
    les at futuresource.com