DNS settings for a webserver

I currently have a windows 2003 AD domain that allows dynamic updates.

In the domain is a webserver that has 2 IP addresses
the webserver is registered in DNS with just the first IP address
I have an alias of www that points to the entry in DNS with first IP address.

My problem:

I want to use the second webserver IP address to host the second website.

This second webserver IP address is not registered in DNS
So how can I add this second IP address in to the DNS server even though the webserver is already registered with its first IP address

what I want is to be able to create an alias for a web site that points to the second IP address of the webserver.

Is this possible or do I have to use the host header name of IIS

I don't understand how 2 IP addresses can be registered in DNS pointing to the same computer???


if you can get your head around this any help would be great

Thorpe,

Adding the second IP Address in the DNS server would certainly not be a problem.

Regardless of what OS the machine with the 2 IP Address is, its possible.

You would be required to create an additional 'A' type resouce record within the Zone and enter the 2nd IP Address.

Let's say for example the subject machine is called 'Server' and your two IP Addresses are 192.168.0.10 and 192.168.0.20 within the domain called 'firewall.cx'.

To be able to distinguish between the two IP addresses, we would give them seperate 'names', e.g the first ip address will point to the server's real hostname 'server', while the 2nd ip address to 'pluto':

In the above example, we would create the following entries:

server.firewall.cx A 192.168.0.10
pluto.firewall.cx A 192.168.0.20

Save your changes and restart the DNS server and goto your workstation and ping each FQDN (Fully Qualified Domain Name):
'ping server.firewall.cx' and then 'ping pluto.firewall.cx',

assuming you have correctly assigned both IP Addresses to the server's nic, you should receive a reply.

That takes care of the IP address side of things.

Coming to your 2nd problem, two internal websites, its quite simple.

Create a 2nd virtual server and goto its properties, assign it to 'listen' only to the 2nd IP address - 192.168.0.20.

Now, one point which I am not 100% sure, but should work is creating the CNAME (canonical) type resource record for this 2nd IP address... logically it should work, but you need to try it and let us know the results as I personaly would be intersted in finding out if it worked.

So, create and additional CNAME record similar to this:

www2 CNAME pluto.firewall.cx

What should happen here is when www2.firewall.cx is entered as a URL, the DNS resolution process will translate as follows:

www2 ---CNAME-> pluto.firewall.cx

---

A

---

> 192.168.0.20

As you can see, www2.firewall.cx will ultimately point to 192.168.0.20, our 2nd IP Address that we previously assigned to the same server.

Give it a try and please do post back the results!!!

Good Luck!

Sounds like the right solution. The CNAME record reads the A type record of the 2nd IP.

Once again this site proves its worth!

Thanks

I set up the new A record and this worked when I ping-ed both IP addresses. I set up the new web alias CNAME and this worked as sell I can host both my websites on the same server with different IPs.

I think what confused me is that I needed to make up a second name for the second IP address. I assumed that 1 machine 1 entry in DNS but I looks that If a PC can have multiple IPs then it can have multiple Names.

Thanks again

It's been just aday since I joined but this site has really impressed . chris and sahir are really doing a real good job here. Thanks to you both for coming up with this site.