[EXT] Xfinity (both ends) - can't ping from users home to office

Spencer Coplin scoplin at f1techgroup.com
Fri Jun 19 15:18:49 UTC 2020

Thank you, he has the xfinity provided router/modem, so no cpe router to make a change on. I don't think we can change it's mac address. Good thought on pursuing it through the business side and I'll proceed with that.

Thank you,


Spencer Coplin

-----Original Message-----
From: Chuck Anderson <cra at wpi.edu> 
Sent: Friday, June 19, 2020 10:13 AM
To: Spencer Coplin <scoplin at f1techgroup.com>
Cc: North American Network Operators' Group <nanog at nanog.org>
Subject: Re: [EXT] Xfinity (both ends) - can't ping from users home to office

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On Thu, Jun 18, 2020 at 11:57:12PM +0000, Spencer Coplin wrote:
> I have a client that is unable to ping his office Comcast Business connection from his home Xfinity connection. It was working a month ago and we can confirm that his connection works over his iphone's hotspot. I am able to ping from my own xfinity residential (same city) without issues. I suspect something in the routing from his home connection is messed up as tracert/ping can't even resolve his office's IP. The client called Xfinity residential support and they blamed the inability to ping the IP on his office vpn connection.
> Has anyone else his this and if so, how was it resolved?

Sort of.  Try having him change the MAC address of his residential CPE router so the BNG sees it as a "new" device.  In my case that resolved connectivity issues after Comcast did some "network maintenance" and broke everything for me.

Alternatively, have you tried working this issue from the Business side?  You'd probably get more leverage that way.

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