Need advice on changing public IP address of Exchange 2000 Server

[ScottWIT]

We currently possess 5 static public IP addresses and need more. But in order to gain more we have to give up the ones we currently possess and then we'll get all brand new ones. Obviously this presents a headache for me. What I'm most concerned about is my Exchange server. How difficult will this process be to give it a new public IP? The ISP will of course give me a specific day that the new IP's will go into effect. Other than changing the NAT info on my firewall and the MX record for my ISP what else do I need to change to ensure a smooth transition (if that's possible)?

 

[MarkArnold]

You'll want the ISP to knock the TTL on the A record down to a very small number of hours indeed, one hour perhaps. That will take care of email waiting to get to you.

Do you need a public IP on your server itself? Usually people put the public IP on the gateway devices (firewall, router, reverse proxy etc.) and port forward inbound. Exchange only needs a couple of ports, it's not usually worth wasting an entire IP address on it.

 

[Zelandakh]

Your firewall really only needs one static IP address on the public side. Then you forward port 25 to Exchange for email, port 1433 to SQL for SQL etc.

Why do you need more than 5?

 

[ScottWIT]

We use our 5 public IP's for VPN access, FTP, remote access to a linux server, website access (we host it) and Exchange.

It was setup that way before I got here. As of now it appears I will be able to take one away from the linux server and use that for what I need so I won't have to change the one we're currently using for Exchange. At least I hope that's the case!

But hey... if there's a better way to do this I'm all ears. I understand the process of forwarding ports but I thought you couldn't (or shouldn't) use one public IP for multiple things such as VPN, Exchange, etc.???