Quick question about DHCP server in Win Server 2003

[latrosicarius]

Hi, this is a simple question, but I don't know the answer.. maybe someone here can help.

I'm trying to setup a proper DHCP server in Windows Server 2003, but need some help.

First let me tell you that I only have 1 server, and it's both the DNS server and DHCP server.

In the DHCP wizard I made my IP range to be 192.168.0.100 to 192.168.0.199. And then I set my router to be 192.168.0.1.

Now on the server, do I need to go to Internet Protocol (TCP/IP) Properties and fill in the info for "Use the following IP address", or can I leave it as "Obtain IP address automatically"?

Same question goes for the box right below that: "Obtain DNS server address automatically" or "Use the following DNS server addresses"?

Thanks!

[TheAnimus]

Depends entirely on the subnet mask you set.

CIDR = Classless InterDomain Routing.

You use a subnet mask to specify when something is local, or should be using a route.

long story short, what your doing is fine, starting at 100-199 for DHCP, and you can then set all Static IP's outside of that range. Use a subnet mask of 255.255.255.0

[latrosicarius]

Thanks for the reply, yes the subnet mask I have is 255.255.255.0. It was the default, so I just left it. But all my clients on the network are internal to the same router, so I guess that would be good.

But I'm sorry: I edited my question a bit right before you answered. It might make it a bit confusing, but in terms of having the server acquire a stataic IP address, I was wondering if I should specify it from the DHCP role or from the TCP/IP properties page.

Thanks

[blueball]

Specify the server IP on the TCP/IP config page - do not user DHCP to give your server an IP because until it is running it cannot get an IP so you are in a vicious circle. Just allocate a static IP to server from outside the scope (or if you feel adventurous allocate from inside the scope but then exclude that IP from the scope)

[latrosicarius]

Thanks, this makes sence. I had it all set up to go, and with your input I pushed the "OK" button.

I guess it works now b/c I did an ipconfig /releas & /renew, and it connects to the clients with the right new IP. Thanks.

Right now, the server's IP is .100 in a range from .100 to .199. It works, but it's not excluded. Are you saying that it would be better if I exclude it or move it out of the range?

Also, about specifying the DNS server? Should I also do it from there as well, or leave it blank? Remember, the same server IS the DNS server, so I'm not sure if I should specify it or not. Right now I did, and it works, but maybe it would be more efficient if I didn't? Just a thought.

[blueball]

if your server IP is inside the scope then you need to add it to the scope exclusions (or make your scope 101 to 199 (easiest way is to select "Address Pool" in DHCP dialog then right click and select "new exclusion range..." and add .100 as an exclusion - that way you don't need to delete/reapply the scope.

I would always tend to allocate static IPs from OUTSIDE the scope but it's neither right nor wrong - more a case of how you want to do it. Outside is neater though.

Setting the DNS server in your IPconfig is recommended. Additionally, within "Scope Options" you can define 003 (a router or gateway IP), 006 (a DNS server) so that DHCP clients will get given the correct info but you've prob already done this.

[latrosicarius]

Originally Posted by blueball

Setting the DNS server in your IPconfig is recommended. Additionally, within "Scope Options" you can define 003 (a router or gateway IP), 006 (a DNS server) so that DHCP clients will get given the correct info but you've prob already done this.

Thanks!

Originally Posted by blueball

I would always tend to allocate static IPs from OUTSIDE the scope but it's neither right nor wrong - more a case of how you want to do it. Outside is neater though.

If all my static IPs were outside the scope from all the dynamic IPs, then wouldn't they not be able to communicate with eachoter?

[blueball]

Only if they were on a different network.

here is an example of a working setup:

DHCP Scope 192.168.1.51 - 192.168.1.100
DHCP Mask 255.255.255.0
DHCP 003 (Router) 192.168.1.1
DHCP 006 (DNS Server) 192.168.1.21

The DNS server is, in this case, also the DHCP server. The DHCP server has it's NIC setup manually as follows:

IP 192.168.1.21
Mask 255.255.255.0
Gateway 192.168.1.1
DNS 192.168.1.21

A mask of 255.255.255.0 and IP range of 192.168.1.x means that the NETWORK is 192.168.1.1 to 192.168.1.254.
The SCOPE is 192.168.1.51 to 192.168.1.100 in the same NETWORK because the mask/IP is the same.

I'm not sure I explained that very well but it's the way IP works. if you want to learn more do a google for subnetting - you'll get bored quick

[latrosicarius]

Thank you, I will give that a try so my network is cleaner like you said