How do you set up DNS on a Tenda router? If you fill both boxes with the same address, it pops up right back when you save

colleague Xiaolin's Tenda AX12 was a tinkering experience last month. removed the dual-band and went through the web backend. A couple of nights ago at eleven o'clock, he sent another message: None of the apps on the TV could be opened, and even if I wanted to install a new one, I couldn't; On the phone, WeChat text can be sent to you, and every web page spins around. I told him not to touch the router yet, gave him a command, and within ten seconds the problem was locked on the DNS—this trip I conveniently jotted down Tengda's DNS change method and pitfalls.

first check if it's DNS fault, don't change it right away

WeChat can send but webpages can't be opened, this combination is almost certainly DNS. The logic is simple: after logging in, WeChat uses a long connection, and the address has already been parsed and cached; Every time you enter a new URL on a webpage, you first have to check the DNS server. If the people asking for directions go on strike, the page will naturally keep spinning.

verification, press Win+R on the computer, press cmd Enter, and enter:

nslookup www.baidu.com

look at the two lines of things that came back. The first line is 'Server,' showing who is answering for you. Normally, it should be the router's address or the ISP's DNS; If a "request timeout" pops up below this line or the address is clearly off, the DNS line can't be found. At that time, the unit at Xiaolin's family couldn't even resolve Baidu's domain name; no matter how many questions you asked, no one would say a word.

there is no WeChat on the TV for comparison, the symptoms look different. My trick for Xiaolin to read is that the built-in app store can be opened, and videos can be opened to start spinning, which is probably DNS; If even the store screen goes white, it means the network is completely disconnected—a completely different matter.

By the way, if WeChat can't send messages or even your IP ping won't work, then DNS isn't the issue. Check the line and optical modem first, and don't waste time on DNS. The only rule for this judgment is: some parts are working, part is not, first suspect DNS; Completely disconnected, first suspecting the wiring .

the DNS entry of the new interface, scroll down in Internet settings

the DNS entry for Tenda's new firmware (AX12, AX3 batch), honestly, isn't exactly hidden, but it's easy to find the wrong place on the first trip. Enter tendawifi.com or 192.168.0.1 in your browser, enter the management password, but be careful not to confuse it with the WiFi password. If you can't tell the difference, check out my article on Tenda initial password. The backend can't even be accessed. The two most common blunders—the phone connecting to a neighbor's WiFi with the same name, and the address being typed into the search bar as a keyword—I opened them one by one in the of 0.1, spent two minutes lining up first, then moved on.

After

in, click 'Internet Settings'. Yes, that's the page for setting up a broadband account and selecting the WAN method. previously written to open IPv6 was also done on this page. The DNS box is placed on the same page. Scroll down, and the "DNS settings" section is set to automatically get by default. Click to select manual, and then the "Preferred DNS" and "Backup DNS" boxes will appear.

my first trip was in the 'Network Parameters' section—that was the old AC system's approach; the new version doesn't even have this menu on the interface. After helping Xiaolin with the changes, I casually browsed through the Tenda WiFi App. I searched the toolbox thoroughly but couldn't find the DNS entry. This is the same temper as Mercury and Xiaomi. Mercury and Xiaomi versions are web backend exclusives. If you want to remotely change DNS on your phone, give up on that idea early.

another entrance to the old AC series, the interface of both generations faces

if your home has an AC10 or AC9 generation machine, the menu names are completely different. After logging in, find "Network Parameters," click "WAN Port Settings," scroll down the page, and you'll find the option to manually set DNS servers. Uncheck the option for automatic retrieval, and the option to select 'Preferred Backup' will appear.

worried about not finding it yourself, here's a clumsy trick: after entering, click through the menu on the left one by one. Whichever page shows the letters "DNS" is it, within two minutes.

the first option as backup can't be filled, I only realized this after being bounced back

the real pitfall lies here. Kobayashi was quick, filling in both boxes with 223.5.5.5—thinking it was Alibaba's DNS anyway, double insurance. Click Save, and a prompt pops up on the page: preferred DNS and backup DNS are not the same , and the configuration is not stored at all.

This is a verification of Tenda's interface being written to death; I later encountered the same blocking method on the old AC10. In principle, backup DNS is meant to fill in when the first option fails. If you fill two identical files, it's like having no backup tire, so Tengda simply won't let you save it. So you have to fill in two boxes:

overseas, 8.8.8.8 is a bit saving. Domestic apps have high latency and occasional packet loss. Parsing can do it, but web pages actually load slower. I previously posted the latency figures from various companies in my post about Mercury. want to understand DNS principles, check the general version , so I won't repeat them here.

the backup box doesn't just treat it as decoration. Less than a week after the change, the DNS system chosen by Xiaolin's family had a malfunction one night, and the whole house web resurfaced again—this time the backup was working, WeChat and most websites worked as usual, and he only discovered it the next day after checking the backend logs. If the first choice is to fill in the same backup option, then tonight you'll be reverted to your original state on the spot. Two boxes to fill two families—that's the purpose.

the change doesn't take effect, check each of the three scenarios one by one

save after filling out, don't rush to declare victory. Tenda switches DNS in broadband dial-up (PPPoE) mode, requiring disconnection and redialing to truly switch over. You can also restart the router in the background and wait a minute or two.

then device caching. On the computer, Win+R presses cmd, enters ipconfig/flushdns, and presses Enter to clear the cache; Just turn off WiFi on your phone and reconnect. The app on Xiaolin's TV finally took thirty seconds of power off and rebooting to recover. Smart devices' cache is even more stubborn than a phone.

The third and most hidden approach: IPv6 takes a wrong turn. Nowadays, both phones and TVs prioritize asking for IPv6 DNS. If the router only changes the IPv4 part, the device might not even use the address you provided. The verification method is still nslookup, depending on whether the returned responder is correct. Also, there are real cases where carriers rush to answer whatever you fill in. The plaintext UDP 53 query is intercepted halfway through and answered for you. the optical modem article wrote about verification and response , but router side can't fix this.

after the changes, if you want to confirm whether it's effective, don't rely on feeling—just type nslookup www.baidu.com again to see if the name on the other end of the reply has changed. Previously, the responder displayed the ISP's DNS name; after changing it, the search should show the router or the new provider you entered. That night, Xiaolin's family relied on this to confirm everything. They checked twice, and the black and white documents were more reliable than anything else. This kind of 'DNS only remembers it exists when it breaks' problem encountered this once in Mercury's melogin troubleshooting , and the final drop was also DNS.

two situations where the change is wasted, think carefully before making changes

First: routers used as APs. My cousin's Tenda AC10 is attached under the main router as an AP, the LAN port IP was swapped back then . When the AP machine is neither responsible for dialing nor sending addresses, DNS is managed by the main router, so changing it on AC10 is just a wasteful effort. Whoever dials will go to their home to change it. Remember this saying to avoid detours.

second type: those who want to speed up by changing DNS. DNS only handles the step of "translating URLs into IPs." The translation speed affects the first page opening, ignoring download speed and video clarity. Before the change, it was 300 MB; after the change, it remains 300 MB. It treats only two issues: certain websites can't be opened, and DNS hijacking to pop up ads.

to wrap up, here's the order: first check nslookup to confirm it's DNS, → go to the tendawifi.com and find your internet settings (old model uses network parameters). → Preferably fill in two different → Save, then restart or redial → Computer flushDNS and phone reconnection → If not, check IPv6 and carrier prompt answers. That night, from discovering the problem to restoring the webpage, it took twenty minutes. The longest lag was when two boxes popped back up when they filled the same space.