Test environment post carrier-grade NAT by ISP

Question

Today I replaced my old router with a new faster router in my home. However, this event appears to have migrated me to carrier-grade NAT'ing by my ISP. I tried with my old router but the same holds true. Along with the change are some annoying aspects, such as DNS resolution appears to be slower. Before the change I used 8.8.8.8 on my router, but no longer appears to be respected as DNS is now handled by my ISP's resolver.

But an even bigger issue now is that my local dev/test environment is impacted networking-wise. For example, my virtualbox VMs that were on a bridge networked all have multiple IPv6 addresses, and internet connectivity is broken. Another strange observation is that even if I power off all my VMs (which were on 10.0.x.x networks), I can ping, and even SSH to a number of 10.0.x.x servers. None of which appear to be mine.

I've read a few posts about people setting up VPN to get control back, and I may setup an openvpn server in my Azure environment. But is there another way? Am I no longer able to use the NAT'ing features of my wireless router?

Answer 1

I would expect you to need to tell the new router what IP address it should use on the ISP side of the router, and possibly also which DNS server or servers it should use. You may also need to make sure it handles local IPv6 addresses, and may need to tell it which local IPv6 addresses it should allow connections for.

Your problem looks like that router could have previously been set up for some other site, and needs to have the setup changed to fit your site instead of the other one.

Answer 2

I spent some time troubleshooting with my ISP and was able to (somewhat) isolate the issue. They provided me with a static IPv4 address to use for the WAN settings in my router, and said I can have my router do NAT/DNS/etc.

in short;

I duplicated the router settings on three different home wireless routers: Netgear wrt54g, an Apple N wireless router, and the new TP-Link AC wireless router. Networking works as expected with the Netgear and the Apple router, but for whatever reason the TP-link router does not behave as expected. Since I don't care to troubleshoot the TP-link router any further I ordered a new Apple AC router.

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Observations:

On the working Netgear and Apple routers my ISP confirms that although I am using multiple client devices, they are all using the same public IP address (expected). With the TP-link router, each client device gets its own public IP address. Even though NAT and settings match those on the netgear and Apple router. We tried renewing DHCP leases and even cloning the WAN MAC, but result was the same.