Fault-tolerant reservations via second DHCP server

[SteveTheGeek]

All,
I currently have a LAN with 20 ordinary DHCP clients and 10 reservation-based DHCP clients (thanks to the faults of H.323 and 1-to-1 NAT they need an unchanging internal IP address). I have two Win2003 AD domain controllers, only one of which is running DHCP currently. I want to add the second to give the DHCP service some fault tolerance.

I have no problem splitting the scopes so that the clients that don't need effectively-static addressing can use either DHCP server's IP offer, but I haven't figured out how to configure the reservations on the second server. Can anyone point me in the right direction, or can I not get there from here?

 

[SimonDavies]

I have to be honest and say that whilst you can set up an 80:20 split scope for redunancy that won't give you the ability to give the same static addresses for those reserved machines.

In all honesty I would look at giving those machines that require it a locally assigned static address rather than a DHCP reserved one, you can remove particular addresses out of the scope so they don't get allocated (causing a duplicate IP address error) and then set up your 80:20 split scope for redundancy.

In the grand scheme of things you have 30 machines in total being serviced by DHCP, reducing that down by 10 won't cause you much of an Adminstrative overhead should you need to make changes (ie DNS server IP address changes etc), you just need to visit 10 machines and make those changes. It would be different if you had 2000 machines with 300 requiring the same address.

Simon

The real world is not about exam scores, it's about ability.

 

[theravager]

Have identical scopes and configure the option confliction detection attempts to about 3. This is found on the properties of the server under the advanced tab.

Other way is to cluster but that's a overkill here.

 

[lhuegele]

With such a small environment, my opinion is that having redundant DHCP is a waste of resources. If your DHCP server is not reliable, then you either have it doing too many other tasks or you need newer hardware.

We have thousands of clients and no redundant DHCP.

Good luck,

 

[Grenage]

That's something you might consider taking up as a project! Setting up a redundant DHCP service takes 5 minutes and no real resources.

"We can categorically state that we have not released man-eating badgers into the area" - Major Mike Shearer

 

[AceOmega]

You can always setup seperate ranges like

SVR1 : 20-150
SVR2 : 150-254

I do not know how many nodes you have on your network so this may not work. You could always subnet but it is a pain.

Frankly I do not worry about this because the TTL is 8 days and I usually can get my server back up by then.