My old Netgear R7000 router has been used for many years and is very stable. In view of the rise of Wi-Fi 6 devices in recent years, I also want to upgrade my home wireless network from Wi-Fi 5 to Wi-Fi 6. Since Wi-Fi 6E devices are not yet popular, I finally chose the Netgear RAX200 router.

In the beginning, everything was perfect, the Netgear RAX200 had a good signal and low latency. But after using it soon I found a problem.

Netgear routers support customizing DNS settings in their network configuration. Users can set the primary DNS address and secondary DNS address and point them to any accessible IP addresses in the Internet or local area network.

I am a technical developer, so the database, NAS, git version control, and testing services are all connected to the home LAN. In order to access these intranet services more conveniently, I set up an intranet DNS to resolve intranet domain names such as “git.local”, “nas.local”, “db.local”, etc.

According to my previous experience of using the Netgear R7000, the router will first access the primary DNS during domain name resolution. If the primary DNS is unreachable, it will access the secondary DNS. If the secondary DNS is also unreachable, the domain name resolution fails.

By installing bind9 on the Raspberry Pi that has been assigned a fixed static LAN IP in the router, we can easily implement the intranet DNS. After configuration, bind9 will directly resolve the intranet domain name and forward the non-intranet domain name to the Internet DNS provided by the ISP for resolution.

In the configuration of the Netgear router, I point the primary DNS to the intranet DNS, and point the secondary DNS to the Internet DNS provided by the ISP. In this way, I can directly access the intranet service through the intranet domain name, and if there is a problem with the intranet DNS, it will not affect my access to the Internet.

I thought everything would be as normal as when I used the Netgear R7000 before, but I found that the intranet domain name began to be frequently inaccessible. At first I thought there was a problem with the intranet DNS, but by checking the logs I found that bind9 did not receive domain name resolution requests sometimes.

So I set up another intranet DNS and pointed the secondary DNS in the router network configuration to it for testing. After testing it was found that, unlike the Netgear R7000, the Netgear RAX200 accesses the primary DNS and secondary DNS selectively with an unknown strategy, possibly based on DNS response time, or other.

I checked and communicated in the Netgear community and found that the Netgear RAXE500 also has this problem, which indicates that all Wi-Fi 6 and Wi-Fi 6E router products of Netgear may have same problem.

If the selective access is based on the response speed of the primary and secondary DNS, it will indeed play a role in improving the speed of Internet access, which is understandable. Therefore, for the normal availability of the intranet domain names, I set the secondary DNS to be empty, so that the router will only access the intranet DNS, although this will result in the inability to access the Internet when the intranet DNS fails.

Maybe in a later version of the firmware, Netgear can provide a configuration option for the user to choose the DNS access policy?

---

Filed under: 未分类 - @ 2022年4月21日 下午2:07