I recently utilized a spare PC to set up a web server at home.

Unfortunately my ISP does not want people on non-business plans setting up web servers. Hence internal IP addresses and the WAN IP address are generated dynamically by default.

I found a way around this by creating a DHCP reservation for the MAC address of my server and forwarding any incoming traffic on port 443 to the reserved IP address.

The next issue was the WAN IP address which is also dynamically generated. My modem has integrated support for noip.com which is a dynamic DNS service that will update DNS servers upon changes to the WAN IP, so I thought I had solved all of my problems.

However, the A record in the DNS management options on Godaddy only accepts actual IP addresses, so I cannot use the domain which was generated by noip.com (thenameofmydomain.ddns.net--this will always be mapped to the WAN IP address) as the A record.

I have been told to create and use a CNAME, but I am still somewhat confused by CNAMES after having read somewhat extensively about them and, more importantly, I do not believe this will solve my problem since I want to use my own domain (spaiglas.com).

Basically all I need to know is how to set a static IP address for the WAN without breaking anything.

The modem I am using is an ActionTec T3200M. The manual with all of the default settings can be viewed here.

I believe I found the necessary options to do so, entitled WAN IP Address, which can be viewed on page 44, but I am scared to touch anything. Is it possible that by changing some of these settings I could break something indefinitely?

1. Current WAN interface is WAN DSL (mine is DSL and not Ethernet)
This option cannot be adjusted in the settings.

2. Select the ISP protocol below
Obviously I would set this to RFC 1483 via Static IP, right?

3. If your ISP Provider requires Host Name/Domain Name, enter it here
I would leave this one alone. I don't see any reason to adjust this.

4. Select the DNS type.
This area confused me since if I select the other radio button, Static DNS Addresses, the Primary DNS and Secondary DNS will populate by themselves with IP addresses that are actually printed on the modem. Where are these DNS servers even located? :/

5. Configure IGMP Proxy.
I am even more confused by this setting. This is the first time I have ever heard of a IGMP proxy. It seems to be a protocol to identify the correct destination for packets?

Can anybody help me figure this out?

Below is my current setup for the domain on the registrar's page. For what it's worth, I'm using the name servers of some shared hosting I purchased a while ago.

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You were advised correctly about a CNAME.

An A record points to an IP address. Simplifying a bit, a CNAMErecord points to another domain - which is what you want.

The idea here would be to register your domain and use your registrar's nameservers. Delete (if it exists) the "www" A record and create a CNAME pointing to thenameofmydomain.ddns.net.

Once this is done whenever someone requests www.mydomain.ext the namesrevers will see its a CNAME and then do another lookup on thenameofmydns.ddns.net to get the IP address.

2 things to note: 1. You need to have the DNS stuff correctly set up in your router or equivalent. 2. Depending on your registration you may or may not need to specify a "." at the end of then of domain.ddns.net - this . has a special meaning - if you leave it out and it's required it will think you mean thensmeofmydns.ddns.net.my.domain - you can often look at how the NS records are specified for the appropriate format.

  • You can't specify a static IP address on your WAN if your ISP does not support it. You might, however, find a VPN provider that will give you a static IP - in which case you can just set that up on your server and ignore the router. – davidgo Aug 18 '17 at 5:51
  • I understand that much. I have registered a domain (spaiglas.com) at Godaddy. Hm... I'm fairly certain it requires an A record, though? Or at least in order to get my SSL certification I had to provide an A record. If I removed the A record would it conflict with the SSL certificate now? I think I'm understanding this. If I remove the A record and add a CName, then when somebody comes to my domain (spaiglas.com) it will check the DNS and redirect to the CName (thename.ddns.net) which is mapped to my WAN IP since there is no A record, correcT? – oldboy Aug 18 '17 at 5:53
  • I'm fairly certain my ISP does support static IP addresses, but for business plans only. However, it would seem that they give both residential and business plans the same modems which obviously have the same options as one another. It seems they haven't properly segregated the two classes and are relying on the consumer's lack of know how instead of actually prohibiting or preventing this. Because there are indeed options in my modem/router's settings which, I believe, allow me to set a static IP address. However, I'm not that knowledgeable when it comes to this stuff. This is my first server – oldboy Aug 18 '17 at 5:55
  • I would be testing these things myself right now, but my ISP won't allow me to access my server from the same network lol. Also, for what it's worth, currently I'm using the name servers of some shared hosting I purchased a while ago. You there? Please help <333 I will attach a screenshot of the current DNS set up. – oldboy Aug 18 '17 at 6:14
  • I doubt its your ISP that stopping you accessing the server - its probably because your router is doing NAT but not "hairpin" NAT - its a common limitation of NAT technology - usually bypassed by a hosts hack or faking DNS in your router if its capable of doing so. – davidgo Aug 18 '17 at 7:01

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