Two DHCP servers

[Tsaico]

I have two networks at home, one with my server 2003 eval and some different rigs, and my normal network with my personal computers and file server. The server 2003 is set up to be a DHCP server and domain server and is working fine, it gives IPs out from a 223.x.x.x pool, while my router gives out ips from the 192.x.x.x pool. My question is, how can I combine them into one network, and manage who gets the 223 numbers and who gets the 192 numbers?

 

[Flatline]

My suggestion would be to turn off the DHCP server in the router and create another zone in your Windows DHCP server.

 

[blcjr]

Originally posted by: Flatline
My suggestion would be to turn off the DHCP server in the router and create another zone in your Windows DHCP server.

Can you clarify what you are recommending here? In DHCP, you don't create "zones", you create "scopes." ("Zones" are what are created in DNS.) In Windows DHCP, it is possible to join multiple scopes into "superscopes" or "multinets," but those are for servicing DHCP requests over networks separated by routers. Tsaico didn't say whether or not he has his two networks on different sides of a router, or whether the router can forward (relay) BOOTP requests. If not, then I don't think he can use multiple scopes from a single DHCP server.

 

[blcjr]

In what sense are these "two (separate) networks"? Unless they are separated by a router that can forward BOOTP requests, I don't think you can do what you are asking.

But I'm not entirely clear what you are asking. Unless you have a subnet mask of 255.0.0.0, then you do not have *.x.x.x networks or subnets. With a mask of 255.255.255.0, they will be *.x.y.z subnets, with only the "z" being a variable served by the DHCP server. There is no way that I know of to use a single DHCP server to service two separate subnets unless they are separated by a router; and even then, the router must either be "RFC 1542 compliant" and act as a relay agent, or else you have to have another server on the subnet that doesn't have the DHCP server configured as a DHCP relay agent.

Perhaps more basic, why do you want to keep the two networks? Perhaps there is an alternative that will accomodate your objectives.

 

[Stealth1024]

what about using VLAN's for each type and tagged stuff so the server can dish out one set of IP's for VLAN1 and another for VLAN2?

traditionally you would use two DHCP server though...

 

[ITJunkie]

Originally posted by: Stealth1024
what about using VLAN's for each type and tagged stuff so the server can dish out one set of IP's for VLAN1 and another for VLAN2?

traditionally you would use two DHCP server though...

Yes...That is what I was thinking myself. The only issue would be Tsaico would need some type of layer 3 switch or bootp forwarding router. I currently have 2 different subnets that use the same DHCP server. I am using a layer 3 switch set to forward BootP requests to the appropriate server. Cake and Pie

 

[Stealth1024]

Originally posted by: ITJunkie

Originally posted by: Stealth1024 what about using VLAN's for each type and tagged stuff so the server can dish out one set of IP's for VLAN1 and another for VLAN2? traditionally you would use two DHCP server though...

Yes...That is what I was thinking myself. The only issue would be Tsaico would need some type of layer 3 switch or bootp forwarding router. I currently have 2 different subnets that use the same DHCP server. I am using a layer 3 switch set to forward BootP requests to the appropriate server. Cake and Pie

Yes I might be spoiled after playing with an awesome 1gb fiber 3COM $$$ layer 3 over the summer while working for a school district... hehe. With no students there over the summer you have time to ask "I wonder what would happen if..."

On another note I can't stand the stupid unintelligent 8 port switches as they never work well with multicast traffic from Ghost. major headaches...

With this new network and Windows2004 and AD we moved from all static IP's to 3 out of 6 dynamic IP's with the rest to be upgraded in time..

RIT uses database technology so you can register your own MAC address via web and the DHCP server will always assign you the same IP. I still haven't figured out how they do this efficiently.

 

[Tsaico]

sorry guys, let me try to clear things up... they are two networks in the sense they are not physically hooked up to each other. One network is built from junked/donated parts that are sorely underpowered for actualy use. My "server" is a PIII450 with 128 megs of ram. Most of the boxes are pII250 or the AMD equiv. Then the ones that are hooked up to the routher are my own and roomies computers that are a bit more up to date. I just wanted to know what would happen if I had one domain group and one workgroup.

So really, my question would be at what point does a box get assigned an IP? Is it when they are turned on or when they log onto a domain? Then would it be possible to have the domain controller serve IPs to anything logged onto domain, and then the router serve everything else?

 

[Disorganise]

As a machine boots up and initialises it's network card it broadcasts for a DHCP server and if one replies it'll request an IP address (assuming configured as DHCP client). This happens way before any domain authentication etc start ocurring.

Your hub or switch won't care how many networks you hook into it, and only devices on the same network will talk to each other unless there's a bridge, router or gateway to connect the networks.
So you could hard code the 192 addresses and DHCP the other range and the two sets will never communicate whilst still ocupy the same switch/hub.

But if you don't want them to commuicate, why do you want to connect them together?

 

[bsobel]

So really, my question would be at what point does a box get assigned an IP? Is it when they are turned on or when they log onto a domain? Then would it be possible to have the domain controller serve IPs to anything logged onto domain, and then the router serve everything else?

When it asks for one, which typically occurs during the boot process (long before logon). Both DHCP servers are going to try and respond, your best bet (for what I think you want) it to do MAC filtering on both so you always know which dhcp server will respond. But if your going to do that, might as well go static ip's and be done with it

Bill

 

[Tsaico]

I have the seperate test network, and I would like to get onto the internet for different resources. Right now it is just DNS, DHCP, and Exchange, no outside world. Can I setup a second NIC to handle the internet traffic and route that from the server to the domain boxes? Would this work out? The domain boxes are on one network, and the appliance router is on another. From the switch of the appliance router patch into NIC 2 on the DHCP 2003 server. Then the 2003 server is connected to the other network by NIC 1. So static IP on Nic 1 and dynamic on NIC 2. Then I can turn the server into internet router also, so it can serve anyone logged onto the domain. Am I on the right path?

 

[cleverhandle]

Originally posted by: Tsaico
I have the seperate test network, and I would like to get onto the internet for different resources. Right now it is just DNS, DHCP, and Exchange, no outside world. Can I setup a second NIC to handle the internet traffic and route that from the server to the domain boxes? Would this work out? The domain boxes are on one network, and the appliance router is on another. From the switch of the appliance router patch into NIC 2 on the DHCP 2003 server. Then the 2003 server is connected to the other network by NIC 1. So static IP on Nic 1 and dynamic on NIC 2. Then I can turn the server into internet router also, so it can serve anyone logged onto the domain. Am I on the right path?

Yup. The default gateway for the 2003 box will be the router appliance, and the default gateway for the test network will be the 2003 box. Since your test network addresses are not publically routable, the 2003 box will need to perform Network Address Translation as well.