[K12OSN] LTSP Setup question.

[Jim Christiansen]

Hello Samps,

Oh man - this is a gem for me, although I'm now asking for some 
clarification.  I'm the teacher who is running one mixed network of K12LTSP 
(80 boxes) with an NT domain and now a 2k or 2003 server for administrators 
all on a new fibre backboned network - suggested last spring, by many on 
this list (to overcome all of the 600 volt power issues in the ceilings of 
my 
no-conduit-toss-the-cat5-anywhere-up-there-in-the-ceiling-it'll-be-fine-kind-of-school). 
  My technicians are way to busy to experiment on a working system and come 
to me for "the plan".  I'm a KISS (keep-it-simple-stupid!) kind of person 
and have said that to avoid DHCP hang ups, I wanted only one dhcp server on 
my network and it would be the k12 server.  This way my thin client will be 
the only boxes using dhcp, period - no problems.  All other boxes are static 
IP.  With a reference to one sheet of paper (my ip number list) I can ssh or 
vnc into any local linux or win box for maintenance - no "I wonder what the 
ip of that dhcp driven box is?"

I'm not too sure what the overall benefit would be to running dhcp for the 
administrator-vp-secretary-councelling win boxes is.  My school won't have 
more than 254 boxes total in it for some time (years).  I guess that what we 
would gain though is better access for notebooks (gota keep the travelling 
big-wigs happy)  or maybe a dhcp wireless access.

Come to think about it, this would be great...  When my kids come in for a 
week-end lan party, they wouldn't have to reset their networks either.

OK, so if my current set up is a 192.168.1.x system, and I wanted to move 
all of the win boxes to dhcp, what would I need to do using the map that 
Samps has given below?

All I would need is for a 192.168.1.x/21 network
one win dhcp server                  192.168.0.1 - 192.168.1.255
one k12 dhcp server                  192.168.2.0- 192.168.3.255
one wireless router gateway    192.168.4.0 - 192.168.5.255 (for notebook 
access)

I know that I've set up my current dhcp server at 192.168.1.0/24

The /21 is what is different.

How will the three systems acces my one IPCop gateway/firewall out of the 
building??

I'm excited to give this a go!

Thanks for any advice,  Jim

<snip>
Terrell Prudé, Jr. wrote:

>
>You're very lucky indeed, unless you're running your K12LTSP servers in the 
>"standard" 2-NIC architecture.  Having eight DHCP servers serving the same 
>broadcast domain can be very, very dangerous.  Yes, I know some

snip


>
>--TP
>_____________________



When running the domain in a private IP block (10.255 and 192.168) you
can run as many DHCP servers as you can make subnets.

an example:


A network, 10.255.0.1/255.255.248.0, has 2046 usable addresses, from
10.255.0.1 to 10.255.7.254 (255 is broadcast and can't be allocated for
other use.

Each of four DHCP servers are set up to use 10.255.0.1/21 as RANGE and
DHCP server 1 is using a SCOPE of 10.255.0.1 to 10.255.1.255
DHCP server 2 is using a SCOPE of 10.255.2.0 to 10.255.3.255
DHCP server 3 is using a SCOPE of 10.255.4.1 to 10.255.5.255
DHCP server 4 is using a SCOPE of 10.255.6.0 to 10.255.7.255

No overlaps in the scopes ensures that there won't be address-clashes on
the network.

If you subnet using a further 1 bit, then you can have twice as many
DHCP servers, each serving half as many clients.


cheers

Samps