magnum99's profile

Regular Visitor

 • 

7 Messages

Wednesday, June 22nd, 2022 8:37 PM

Closed

Extend Comcast DHCP Server WAN LEASE TIME to 24 hours

I cannot get anyone at Advanced Technical Support who understands or can Extend the Comcast DHCP Server WAN LEASE TIME to 24 hours.  It is current set to 1 hour.  Can anyone help?

Expert

 • 

109.1K Messages

3 years ago

No one here will be able to do that either. It is controlled by the network engineers and / or the Headend Techs. Short-duration leases are typically assigned when maintenance and / or upgrades  are being performed on the local system. It should return to a longer duration when these are completed.

Are you actually experiencing any problems / connection drops ?

Regular Visitor

 • 

7 Messages

3 years ago

Yes ... after 3 to 4 days I lose 2.4 Internet Connectivity due to a jam in renewing the leases and I have to reboot the modem which clears the jam and starts over.  Below is the Luxul Router Log showing the renewed WAN lease time for 7200 seconds (2 hours).  It needs to be set to 24 hours (86400).  Jack

Wed Jun 22 03:15:00 2022 cron.info crond[3333]: USER root pid 11830 cmd logrotate /etc/logrotate.d/domotz
Wed Jun 22 03:15:58 2022 daemon.notice netifd: wan (3646): Sending renew...
Wed Jun 22 03:15:58 2022 daemon.notice netifd: wan (3646): Lease of 73.77.22.192 obtained, lease time 7200

Problem Solver

 • 

1.5K Messages

3 years ago

Actually, it shouldn't matter.  DHCP renew is supposed to retry on fail.  The retry interval usually isn't really exactly random, but hops a bit in increasing intervals.  In theory, it should retry forever no matter what the lease time is set to.

There's some tunable parameters if it's ICS's version (most use it) in dhclient.conf  https://kb.isc.org/docs/en/isc-dhcp-44-manual-pages-dhclientconf I don't know if you can get to it in your router.

Official Employee

 • 

2.6K Messages

3 years ago

Hi, @magnum99. I understand how the shortened lease time can be frustrating. @EG is correct with their comment. Are you noticing any issues with your service other than the short-term lease?

Regular Visitor

 • 

7 Messages

@XfinityRay​ The problem I am having is the the 2.4 GHz Wifi gradually decreases from 85 Mbps to zero over 2 or 3 days and then says no internet connection. The 5.0 GHz Wifi works fine at 250 Mbps and never has a problem. My hard wire runs at 800 Mbps without any problem. My RING, THERMOSTATS and GARAGE Doors only have 2.4 GHz, so when the 2.4 goes down, I can no longer operate them, so I have to reboot the Modem (Netgear 1200 Nighthawk with Luxual ABR-5000 Router & XWC-2000 Controller). I sent the the Router Log and WireShark Capture (packets) to Expert at Luxul and he said the primary problem is my WAN Lease Time of 3600 to 7200. He said, the 2.4 jams up renewing leases after about 2 days.

Any ideas on how I can keep my 2.4 running for more than 2 days without rebooting modem.  

Official Employee

 • 

352 Messages

That is a great question! Are you able to have the 5 GHz network broadcasting too, as backup?

I no longer work for Comcast.

I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Please, mark a reply as the Accepted Answer.tick

Regular Visitor

 • 

7 Messages

Wired and 5.0 GHz are fine, only 2.4 loses internet.  Below is the Luxul log showing the 7200 second (2 hour) lease time.  It has been like that for several months.  Is there any way to get a message to the network engineers and/or the Headend Tech to change the lease time.  I have a luxul log from October 2021 for 14 hours and there is no lease time, so it is for the last few months.

Wed Jun 29 14:14:49 2022 daemon.notice netifd: wan (3633): Sending renew...

Wed Jun 29 14:14:49 2022 daemon.notice netifd: wan (3633): Lease of 73.77.22.192 obtained, lease time 7200

   

Problem Solver

 • 

1.5K Messages

@magnum99​  Yeah, but if the 5G and Ethernet work, you've got the lease. (successful renew).  Any other logs you an look at with the controller?  Interface logs, specifically for the 2G radio/access point connections to it?  General error logs?  Anyway to turn up logging/debugging verbosity?

Might be an entirely different problem.  Is the WiFi controller getting an internal DHCP lease from the router?  I'd set static on that first before trying to debug it more. 

(edited)

forum icon

New to the Community?

Start Here