Question, Getting the "Your ISPs DHCP does not function properly" issue?

[GronamOx]

Hey all,

So last night at like 2:30 in the morning my net cut out randomly, so I logged onto the webui and got the "Your ISPs DHCP does not function properly". If anyone could help or has any suggestions I would be grateful. What I have determine is I'm pretty sure there's nothing wrong on my ISPs side of things, it appears to be an issue with the router.

My ISP: Comcast
Router: RT-AC87R, firmware version 3.0.0.4.380_7743, Operation Mode is Wireless Router
Modem: Cisco 3941T in bridge mode

Edit:

Well after 17 straight hours the issue has been resolved. I have no idea what the comcast tech did because all he told me was complete bs. Thanks everyone for the suggestions and the help.

 

[ColinTaylor]

Go to WAN > Internet Connection > Special Requirement from ISP and change the setting of "DHCP query frequency".

See if that makes a difference.

 

[GronamOx]

Go to WAN > Internet Connection > Special Requirement from ISP and change the setting of "DHCP query frequency".

See if that makes a difference.

Will try when I get home from work

 

[VANT]

Set to NO - "Enable VPN + DHCP Connection"

 

[Observation2017]

Actually ISPs DHCP service will go down for short periods of time when they are doing maintenance usually in the middle of Sunday O'Dark hours.

But more likely its your cable or ADSL modem needs a power off reset (unplug it 30+ seconds to be thorough). Basically no Internet reaching the router because modem froze up/lost sync...which includes no DHCP to start off. Occasionally you lose ISP cable modem provisioning especially if you own your own modem. Then you have to call Tech Support who should during diagnostic resend provisioning (what speed is authorized etc).

 

[GronamOx]

Actually ISPs DHCP service will go down for short periods of time when they are doing maintenance usually in the middle of Sunday O'Dark hours.

But more likely its your cable or ADSL modem needs a power off reset (unplug it 30+ seconds to be thorough). Basically no Internet reaching the router because modem froze up/lost sync...which includes no DHCP to start off. Occasionally you lose ISP cable modem provisioning especially if you own your own modem. Then you have to call Tech Support who should during diagnostic resend provisioning (what speed is authorized etc).

I wish it was just maintenance, I've been working with Comcast Customer Care via twitter DMs since 3am. They didn't do maintenance and we tried power cycling to no avail

 

[Observation2017]

I wish it was just maintenance, I've been working with Comcast Customer Care via twitter DMs since 3am. They didn't do maintenance and we tried power cycling to no avail

Check your modem sync lights. That is the hard test of reality.

If your modem and the local cable router both lost your provisioning parameters - a power cycle will not work. I had that happen and they persistently told me the same thing. Its your desktop. I had to demand a supervisor because " modem sync lights are not on correctly and you do not even know what lights are supposed to be on. I got your name and I will be sure to mention it when I cancel my service." Level 1 Helpdesk is to screen out idiots and those too polite to assert themselves. You got to be rude to get away from Level 1 and level 2 Help desk. Level 3 Help Desk might admit you got a Tech Support issue. You don't have be too rude to Tech Support Level 1 - just tell them what lights are on modem and after power cycle fails to fix, they will be will to pass you up the chain. Level 2 will actually volunteer to pass you up when they cannot solve it quick.

From experience if someone at HQ deletes your privately owned modem from authorized list it will trickle down automatically. Not all deletions are intentional. Nor are deletions necessarily in all databases. Sometimes processing cause what is probably supposed to be a temporary change to persist or fail to get restored in their middle databases -- from what I can tell. Sometimes the Level 2/3 Tech guy sees the provisioning problem and sometimes his diagnostic script fixes it...temporarily.

"your modem is resetting so let me see if I can find the problem...no problems I can see. Oh its working now? Well good day."

My experience is that if the Tech guy sees nothing to fix, the problem reoccurs.

 

[Observation2017]

Bad Provisioning can lead to no modem sync or not recognized as legal DHCP client (MAC not in local neighborhood router tables of legal clients).

Also my Dad's cable ISP (?Grandview?) makes no bones about discouraging privately owned modems. In those words. They say that although you are legally allowed to own your own, most people will find it highly inconvenient. They will tell you which models definitely will or will not work and a nationwide timeframe. If you are alert and read their site a lot you will be able to guess firmware changes are coming.

They will not update your firmware for compatibility etc when they change theirs. They are under no obligation to inform you of when your local neighborhood will change firmware. Moreover Customer Service may not be able to tell you about local firmware version and change dates if you call. Their information on firmware tends to be part of big picture start dates for regions or large metropolitan areas. Details are up to working crews and techs. They also implied that they won't make changes so that provisioning parameters are permanently stored on your modem as company owned routers have.

So totally up to user guess which firmware to flash when and for modem to read provisioning parameters from the neighbor cable router at every boot.

And this normally works except if there is a critical difference in firmware or the local neighborhood cable router forgets your modem provisioning. Router still operates good and so do all the company modems even if it forgets all modems...which is probably more rare than forget a private or two because they just do not have an key entry for company owned modem.