AC87U Internet disconnect

[lifeisfun]

Not sure why but in the past couple weeks I started to get short internet connection dropouts.
When I check logs I get this error, sometimes several times in row, sometimes only once


Mar 6 07:42:38 dnsmasq[225]: Maximum number of concurrent DNS queries reached (max: 150)
Mar 6 07:45:54 dnsmasq[225]: Maximum number of concurrent DNS queries reached (max: 150)
Mar 6 07:45:59 dnsmasq[225]: Maximum number of concurrent DNS queries reached (max: 150)
Mar 6 07:46:05 dnsmasq[225]: Maximum number of concurrent DNS queries reached (max: 150)
Mar 6 07:46:11 dnsmasq[225]: Maximum number of concurrent DNS queries reached (max: 150)
Mar 6 07:46:17 dnsmasq[225]: Maximum number of concurrent DNS queries reached (max: 150)


No change in hardware or anything else that I can think of
Can someone please suggest how to check what is causing this problem?
AC87U 384.9

Thanks

 

[ColinTaylor]

Do you have anything on your router that could interfere with DNS lookups, like ad-blockers, DNSFilter or VPNs?

 

[lifeisfun]

Do you have anything on your router that could interfere with DNS lookups, like ad-blockers, DNSFilter or VPNs?

Thanks for reply
Only VPN server running but that was running for years without issue. Tried to disable it but it did not make any difference.

 

[ColinTaylor]

Only VPN server running but that was running for years without issue. Tried to disable it but it did not make any difference.

VPN server shouldn't be a problem, VPN client might have been.

You could turn on detailed logging for dnsmasq but you would be flooded with information. Does this happen in a predicable way? At a certain time of day, or when you're doing a particular task?

 

[EmeraldDeer]

• Unusually high rate of queries and/or slow response
• What is the output of "sort /etc/dnsmasq.conf | grep -v dhcp-host"?
• Using Diversion?
• Using stubby?

 

[lifeisfun]

VPN server shouldn't be a problem, VPN client might have been.

You could turn on detailed logging for dnsmasq but you would be flooded with information. Does this happen in a predicable way? At a certain time of day, or when you're doing a particular task?

I'm the only one connecting to the VPN and very rarely when not home. So not caused by that.
Sometimes I feel that there is pattern to it but probably not
It usually disconnects for 30sec to a minute and then it works fine again.
I'll try the detailed logging if I find it

Thanks for your patience

 

[lifeisfun]

Another thing installed is the ASUS Downloader, could that cause problems?
Also running for years.

 

[ColinTaylor]

Unless you happen to be sitting in front of your computer when it happens it could be difficult to diagnose.

It could simply be that your upstream DNS server is unreliable. What DNS server(s) are you using? Try using a different one, like Google's (8.8.8.8).

 

[lifeisfun]

Unless you happen to be sitting in front of your computer when it happens it could be difficult to diagnose.

It could simply be that your upstream DNS server is unreliable. What DNS server(s) are you using? Try using a different one, like Google's (8.8.8.8).

Actually it happened once while I was sitting at the PC so I logged in, and in Log discovered those lines
Changed DNS from auto to manual 8.8.8.8 and 8.8.4.4, will see if that helps.

Thanks

 

[lifeisfun]

Well, just happened again
Mar 6 12:10:32 dnsmasq[225]: Maximum number of concurrent DNS queries reached (max: 150)
Mar 6 12:10:38 dnsmasq[225]: Maximum number of concurrent DNS queries reached (max: 150)
Mar 6 12:10:44 dnsmasq[225]: Maximum number of concurrent DNS queries reached (max: 150)
Mar 6 12:10:50 dnsmasq[225]: Maximum number of concurrent DNS queries reached (max: 150)

 

[ColinTaylor]

Well, just happened again
Mar 6 12:10:32 dnsmasq[225]: Maximum number of concurrent DNS queries reached (max: 150)
Mar 6 12:10:38 dnsmasq[225]: Maximum number of concurrent DNS queries reached (max: 150)
Mar 6 12:10:44 dnsmasq[225]: Maximum number of concurrent DNS queries reached (max: 150)
Mar 6 12:10:50 dnsmasq[225]: Maximum number of concurrent DNS queries reached (max: 150)

Well that's good in a way. At least it seems to rule out a problem with the destination DNS server.

It's possible that you're experiencing a complete loss of internet and the DNS messages are just a symptom of that.

Can you set up a continuous ping on some device that's always on. For a Windows PC that would be:

ping -t 8.8.8.8

Then the next time it happens you can look at the pings to see if you've lost connection to the internet.

 

[lifeisfun]

Well that's good in a way. At least it seems to rule out a problem with the destination DNS server.

It's possible that you're experiencing a complete loss of internet and the DNS messages are just a symptom of that.

Can you set up a continuous ping on some device that's always on. For a Windows PC that would be:

ping -t 8.8.8.8

Then the next time it happens you can look at the pings to see if you've lost connection to the internet.

Great, on it
Thanks

 

[Thorton]

I also run AC87U and the same issue (connection drops for 2-5 minutes) started occurring once or twice a week since upgrade to 384.9. Since that never happened before, I blamed my ISP, but it looks I'm not the only one. I didn't check logs, but will do next time when connection drops, to see if error is the same. For now, I can only tell that router GUI displays "not connected" message in main page when this happens. Which is strange and incorrect because I have my TV plugged in to the router (using IPTV) and IPTV works perfectly when router claims that I'm "not connected".

 

[EmeraldDeer]

I also run AC87U and the same issue (connection drops for 2-5 minutes) started occurring once or twice a week since upgrade to 384.9. Since that never happened before, I blamed my ISP, but it looks I'm not the only one. I didn't check logs, but will do next time when connection drops, to see if error is the same. For now, I can only tell that router GUI displays "not connected" message in main page when this happens. Which is strange and incorrect because I have my TV plugged in to the router (using IPTV) and IPTV works perfectly when router claims that I'm "not connected".

What happens if you change Administration/System/Network Monitoring to Ping 1.1.1.1

 

[Thorton]

Not very sure if I understand it right. Maybe you could explain a bit more, please?

 

[lifeisfun]

So, lost internet connection again while ago, ping to 8.8.8.8 timed out and this time it showed actually WAN disconnected in the router GUI
but lines in the log are very different
Mar 7 04:28:27 ovpn-server1[30560]: 185.200.118.47 TLS: Initial packet from [AF_INET6]::ffff:185.200.118.47:50017, sid=12121212 12121212
Mar 7 04:29:27 ovpn-server1[30560]: 185.200.118.47 TLS Error: TLS key negotiation failed to occur within 60 seconds (check your network connectivity)
Mar 7 04:29:27 ovpn-server1[30560]: 185.200.118.47 TLS Error: TLS handshake failed
Mar 7 04:29:27 ovpn-server1[30560]: 185.200.118.47 SIGUSR1[soft,tls-error] received, client-instance restarting

It reconnected as usual 1 minute or so later

 

[ColinTaylor]

So, lost internet connection again while ago, ping to 8.8.8.8 timed out and this time it showed actually WAN disconnected in the router GUI
but lines in the log are very different
Mar 7 04:28:27 ovpn-server1[30560]: 185.200.118.47 TLS: Initial packet from [AF_INET6]::ffff:185.200.118.47:50017, sid=12121212 12121212
Mar 7 04:29:27 ovpn-server1[30560]: 185.200.118.47 TLS Error: TLS key negotiation failed to occur within 60 seconds (check your network connectivity)
Mar 7 04:29:27 ovpn-server1[30560]: 185.200.118.47 TLS Error: TLS handshake failed
Mar 7 04:29:27 ovpn-server1[30560]: 185.200.118.47 SIGUSR1[soft,tls-error] received, client-instance restarting

It reconnected as usual 1 minute or so later

Are there any other messages at all in the log for this period other than the ones you posted?

 

[Thorton]

and this time it showed actually WAN disconnected in the router GUI

Exactly what happens to me. But like I said, I believe it's incorrect because my IPTV continues working when WAN is listed as disconnected.

 

[lifeisfun]

Are there any other messages at all in the log for this period other than the ones you posted?

No, nothing within 20 minutes from that event

And it just happened again

Mar 7 07:12:38 dnsmasq-dhcp[7350]: DHCPOFFER(br0) 192.168.1.128 b0:4e:26:19:59:53
Mar 7 07:12:38 dnsmasq-dhcp[7350]: DHCPREQUEST(br0) 192.168.1.128 b0:4e:26:19:59:53
Mar 7 07:12:38 dnsmasq-dhcp[7350]: DHCPACK(br0) 192.168.1.128 b0:4e:26:19:59:53 TPlink-Outlet3
Mar 7 07:36:04 dnsmasq[7350]: Maximum number of concurrent DNS queries reached (max: 150)
Mar 7 07:36:10 dnsmasq[7350]: Maximum number of concurrent DNS queries reached (max: 150)

 

[lifeisfun]

Exactly what happens to me. But like I said, I believe it's incorrect because my IPTV continues working when WAN is listed as disconnected.

Are you sure your IPTV is not buffering and that's why the disconnection is not seen on that device?