Multiple Physical (and Virtual) servers (mail, web, etc.) on single link. Can I use DDNS to use top level domains to each box?

Question

This all started last year when I switched to a LISP based solution for my old "C" address block without the expense of T1 lines. I have a cable link and a dsl link into my Cisco 2800 that then processes LISP and feeds the LAN. I have/had at least one IP address (ipv4) for each separate physical machine. Some machines had multiple IPs for various virtual hosting duties. I am now going to lose my LISP service and need to keep everything running.

Is there a way to use Dynamic DNS to allow continued regular use. I.e., user types domainname1.com and gets to physical computer A, user types domainname2.org and gets to physical computer 2, etc, etc.

If I could get time warner/verizon/etc to publicize a SINGLE /24 I could go back to using it normally. These blocks are all portable.

If not...anyone have some working suggestions?

Thanks,

Rick

Answer 1

You can have all the services resolve to a single IP, then use port forwarding to direct the traffic to the appropriate server. This is a commonly used solution.

If you are running an email server you should either get a fixed IP address, or use your provider's relay for outgoing email. You wouldn't need a DDNS solution in this case. Many providers dynamic IP addresses are listed in blacklists, and this can cause delivery problems.

You may be able to use BGP to push routing for your IP block. You will need to redo this every time your dynamic address changes. This may not be stable. However, that appeared to be the solution used by one of my previous ISPs.