AC-3200 ISP's DHCP issue

[Eric Mitchell]

Aloha all! I have an AC-3200 on the latest Merlin that I've been using for a couple of years. It's been between three houses, three modems, always worked fine.

This morning I upgraded from 300Mbps to 1Gps at the house, and switched again to a new modem (needed DOCSIS 3.1 for the 1G connection). Upon plugging the new modem into my router, it continues to give me the "your ISP's DHCP does not function correctly" error and I have no internet access.

So far, I have tried

• Plugging modem straight into Laptop, works fine
• Changed DHCP settings from agressive mode to normal, same
• Factory Reset whole router, same issue
• Go through internet setup on new reset router, didn't help.
• Turned all devices off for 30 minutes, turned modem back on, once booted booted up factory reset 3200, same error.
• Grabbed a brand new RT-AC68U out of the box, plugged it up, boom works fine.
• Compared WAN settings between the 68 and the 3200, they're the same.

This router was working fine about 10 minutes before we turned it off and hooked up the new modem. So I know it isn't bad. And as I said, it's been through 3 locations and 3 different modems and this router always worked perfectly.

The only thing I haven't done is flash an Asus firmware back on the router instead of the Merlin firmware....but don't know why that would work.

About to just go and buy a new router, but hate to as the 3200 was always perfect....until now. This is frustrating! Anyone have any other ideas?

Mahalo from Maui

 

[ColinTaylor]

It sounds like you've tried everything. I think your own suggestion is the best at this point , installing Asus' stock firmware. Presumably that's what you had on the RT-AC68U as it was straight out of the box. So that would be a more equal test, especially if you could load the same firmware release.

Other than that you might try cloning the MAC address of your laptop or the RT-AC68U as both of those are known to work. Perhaps the MAC address of the AC-3200 has been blacklisted by your ISP for some reason.

Good Luck.

 

[xtropodx]

The only thing I haven't done is flash an Asus firmware back on the router instead of the Merlin firmware....but don't know why that would work.

This. Roll back & start from scratch. If this works this perhaps the latest firmware has done something, as the latest merlin firmware hasn't been out that long & so maybe you've stumbled onto something. I have a RT-AC3200 & I've encountered issues with it (& still do) but usually because it wasn't factory defaulted/reset after a firmware update.
Buying new hardware should be a last resort.

 

[Eric Mitchell]

Thanks both, I'm going to restore to factory fresh and clean the nvram tomorrow. If that doesn't work, I might throw advanced tomato on it and see what happens.

I am getting a good 600Mbps download on the temporary solution

 

[Eric Mitchell]

Aloha all! So, I restored to a the latest factory firmware, NOT Merlin....and it works!!!! So something in the Merlin firmware must be messing it up...strange but true.