Hi  @ProSumerTester 

The ER7206 is not using the latest firmware. Please update the gateway and see if the issue persists:

https://static.tp-link.com/upload/firmware/2024/202406/20240620/ER7206(UN)_V1.0_1.4.2%20Build%2020240618.zip

If it can't help, please refer to the following to troubleshoot:

1. Since wired and wireless clients are both having the issue, there may be something wrong with the internet service provider. Please first check this;

2. When the internet drops, will all clients be affected simultaneously? Or are some clients still working normally?

3. When the internet drops, will the affected clients keep the valid IP address? If you ping 8.8.8.8 on the clients, will it reply?

4. How will the Internet recover? Do you need to reboot the router, or will it return automatically?

5. How often will the issue happen?

What kind of controller are you using? What was the firmware version before the last update?

  @Vincent-TP 
Thank you for taking the time to respond.

GW firmware as far as I can see its up to date. Never tried to download and manually update but I did it this time as you suggested.

1.Internet provide was stable all these years but I checked their website for status and its all good.

2. Most devices including server and clients are affected but some can still access internet for a min or 2 and then they also loose connectivity. Worth to mention that internal traffic to servers running on local LAN is still possible and working.

3. When internet connectivity is lost devices keep their IP and yes they can ping outside IP but can not resolve url addresses (nslookup does not resolve)

4. I wait for a few minutes and internet is back.

5. I did not keep track of how often but I would say at least 4-5 times a day.

As you might notice in my signature I use hardware controller C200. Lately performance of this controller is more sluggish then usual.

Hi  @ProSumerTester 

Thanks for the reply.

When internet connectivity is lost devices keep their IP and yes they can ping outside IP but can not resolve url addresses (nslookup does not resolve)

>>>It seems like the issue is related to the DNS server of the network. Would you please share a screenshot of the DNS config page of the network?

If change it to 8.8.8.8, will the issue disappear?

  @Vincent-TP 

I also suspected DNS but as I wrote previously I changed from private DNS that runs on my local network to public one 9.9.9.9 and 9.9.9.11
 

Here is screenshot of my home wifi network

Advanced DHCP options are not in use

Hi  @ProSumerTester 

Thanks for the info.

You mentioned that the issue occurred after the firmware update of the controller.

What is the previous firmware of the OC200?

If you don't mind, could you please Force-Provision the gateway router and see if the issue persists?

Config > Manage Device

Note: This will make you lose Internet for a some minutes.

  @Vincent-TP 

I was trying to find what was the previous version of C200 controller in logs but due to retention time and amount of logs generated, they  are generally flushed daily and I was unable to pinpoint the version. I am updating firmware week after realease so my guess is that C200 was running version before last.

I also forced provisioned gateware as suggested.

is there a way to see when dns issue occures in logs and not wait on users to complain that internet is not working?

Hi  @ProSumerTester 

Unfortunately, there is no such log we can check directly from the controller.

Here is another config you can try:

Go to Settings > Service > DNS Proxy

You can try selecting multiple types to test.

If that can't help, could you please share a screenshot of the nslookup results when the issue happened?

  @Vincent-TP 

Does this mean that when using DNS proxy there is no need for dns setting on network or do they work hand in hand ?

Hi  @ProSumerTester 

Yes, with DNS Proxy configured, no need to configure LAN DNS.

If you configured both of them, the network will use the one you configured under DNS Proxy page.

DNS Proxy provides the LAN side clients with the DNS query service. It forwards the DNS request from the LAN side clients to the selected upstream DNS server and forwards the DNS reply accordingly.

DNSSEC (DNS Security Extensions), DoT (DNS over TLS), DoH (DNS over Https) and DNS Override are four security options for DNS Proxy. DNSSEC will verify the integrity of DNS records, and DoT / DoH will encrypt the query. When DNS Override enabled, DNS requests from the selected LAN network will be intercepted and forwarded to a specific DNS server, even if the DNS server set on the client device is not the router's LAN IP.

All of the four options need an upstream DNS server that supports them.

ProSumerTester wrote

  @Vincent-TP 

 

Does this mean that when using DNS proxy there is no need for dns setting on network or do they work hand in hand ?

  @ProSumerTester
It does not solve the issue as I still see that internet drops random times during the day.

Seems there is no help for this.