WAN_Connection: ISP's DHCP did not function properly.

[Rguiher]

The documentation is wrong. It's 12 requests per minute, one every 5 seconds. This means it's 0.2Hz.

Well that makes more sense. Scary that someone at Asus knows the term "Hz" but doesn't understand the definition, but that's a different issue.

 

[Rguiher]

the lease had been changed to only 1 hour!!!! So, my hypothesis is that the isp changed a policy, and either the cable modem or the Asus somehow got the old lease time stuck.

Mystery deepening a bit - the router ended up restarting itself a couple of minutes later with kernel errors complaining about nvram corruption, and post recovery the lease time showed as a day - same setting I have for the router's dhcp server to my lan. So now I'm not sure if it's router hardware or a bad config, or there is a bug with the handling of the dhcp renewal. I will factory reset today and debug further, and follow up when I've got a conclusion. Still feels like I'm on to something with the renewal cycle though...

 

[Doug Nix]

I was having the same problem with my old AC68U repeatedly dropping the WAN connection. The problem for me began in mid-Aug, and I've been working on troubleshooting it since. My ISP, Rogers Communications, checked external wiring and swapped the Hitron CODA-8562 that they supplied, but to no avail. When the problem started, I tried re-flashing the firmware and doing an M & M setup, still no joy. I decided that perhaps my 3-year-old AC68U was faulty, so I decided to buy a new router. I ended up purchasing the GT-AX11000 because that was what I could get locally that also had a good rating on the SNB Charts. Still no joy. Rogers convinced me that the CODA was legacy gear on their network and that I needed the newer "Ignite" modem they were offering (actually an Arris XB7), so I caved and swapped for the more recent gear and a slightly higher monthly fee. Still no joy. Then I found this thread, turned off the network monitoring function (Administration > System > Basic Config). Over the last 24 h internet access has remained steady and fast, so I'm hopeful. I'll update this thread with any other newsworthy items over the next few days. If all goes well, I will be installing the latest version of Merlin in a month or so.

Thanks for the great information, everyone.

 

[Doug Nix]

I was having the same problem with my old AC68U repeatedly dropping the WAN connection. The problem for me began in mid-Aug, and I've been working on troubleshooting it since. My ISP, Rogers Communications, checked external wiring and swapped the Hitron CODA-8562 that they supplied, but to no avail. When the problem started, I tried re-flashing the firmware and doing an M & M setup, still no joy. I decided that perhaps my 3-year-old AC68U was faulty, so I decided to buy a new router. I ended up purchasing the GT-AX11000 because that was what I could get locally that also had a good rating on the SNB Charts. Still no joy. Rogers convinced me that the CODA was legacy gear on their network and that I needed the newer "Ignite" modem they were offering (actually an Arris XB7), so I caved and swapped for the more recent gear and a slightly higher monthly fee. Still no joy. Then I found this thread, turned off the network monitoring function (Administration > System > Basic Config. Over the last 24 h internet access has remained steady and fast, so I'm hopeful. I'll update this thread with any other newsworthy items over the next few days. If all goes well, I will be installing the latest version of Merlin in a month or so.

Thanks for the great information, everyone.

Update:
15 days and I haven't needed to restart any of my network hardware! I can say that disabling the DNS or Ping monitoring of my internet connection solved the problem for me. Additionally, I was able to install my old AC68U as an AI Mesh node to improve coverage in an area of my home where previously the coverage was OK, but not great. All working well.

Thanks to everyone who contributed to this thread. @LD&D, I am going to add disabling this feature to my M&M config procedure. Might be worthwhile considering adding this to your M&M post as well.

 

[k0rp]

Update:
15 days and I haven't needed to restart any of my network hardware! I can say that disabling the DNS or Ping monitoring of my internet connection solved the problem for me. Additionally, I was able to install my old AC68U as an AI Mesh node to improve coverage in an area of my home where previously the coverage was OK, but not great. All working well.

Thanks to everyone who contributed to this thread. @LD&D, I am going to add disabling this feature to my M&M config procedure. Might be worthwhile considering adding this to your M&M post as well.

I am having similar issues with a AC68U to everyone in this thread and disabled DNS and Ping monitoring with no effect. Merlin version: 386.3_2.

 

[k0rp]

I am having similar issues with a AC68U to everyone in this thread and disabled DNS and Ping monitoring with no effect. Merlin version: 386.3_2.

Decided to bite the bullet after trying just about everything else (DHCP query intervals, various admin settings, replacing ethernet cords, etc.) and performed a downgrade to Merlin 384.19. I will report back if I keep experiencing any DHCP issues from with my RT-AC68U but so far so good.

My current network setup for anyone else trying to troubleshoot this issue:
Verizon FiOS internet (ONT) ---- Cat 6 ----> RT-AC68U (running Merlin 384.19) ----> switch(es) ----> pihole

EDIT: 1 full day since firmware downgrade. No issues yet and I already have noticed my IP change at least 1 time.

EDIT #2: I'm now noticing my upload speeds drop from 800-ish Mbps down to under 100 Mbps with no change to download speed. No issues with actual internet access yet.

EDIT #3: I restarted both my PC and laptop (which in the diagram above, sit at the same topology as the pihole) ONLY and my upload speeds are back to normal. I did not restart/reboot my router or ONT, it just magically fixed itself?

EDIT #4: Just lost connectivity (roughly 2 days of uptime). Router indicated that I was still connected to the internet, with 1hr 50 minutes left on my DHCP lease. Tried manually restarting WAN via router, which resulted in the "Your ISP's DHCP does not function completely". Rebooted router, connectivity restored, same IP address as before I lost connectivity, but now I'm seeing much slower upload speeds again on several devices even after restarting them. Performed an additional router reboot and upload speeds seem back to normal on all devices. New IP address acquired during second reboot. I'm about at my wits end with this, anyone have any suggestions for a new router with similar features to the RT-AC68U?

EDIT #5: Got on the horn with a Verizon agent, asking them to take a look. They did a "refresh" of my internet, which required another router reboot and it seems like I got another fresh IP. After that they said that since I'm connected to the internet and everything on their end looks good, that they can't do anything else. This is so much fun.

EDIT #6: After that talk with Verizon yesterday, I turned off my router for a solid 30-45 minutes and went for a walk. When I returned, I turned my router back on and it's been pretty solid since. Let's see how long this lasts (16ish hours so far).

EDIT #7: No full internet connectivity drops, yet (36+ hours). I am noticing that sometimes my internet speeds (from what I can tell, mostly upload) slows down to a snail's pace, sometimes as low as 1Mbps. I have a work laptop that's connected to my network (wired) and it seems to lose VPN connectivity when this happens, but it is able to reconnect shortly. During this time, I can still access the internet, but it feels like something is going on. My IP seems to be the same the entire time.

EDIT #8: After experiencing the above with what appears to be speed degredation, after 10 minutes we're back up to 100% speeds. Bizarre.

EDIT #9: I thought it was finally "fixed". Nope. Internet just cut out and a router reboot didn't fix it, as it started displaying the ISP DHCP issue on the home screen. Rebooted the router again, finally have internet again. Ok, now I'm at my wits end.