I've been hitting a bunch of brownouts and such lately with all the rain and wind. Sometimes I end up losing the internet connection when this occurs. I'm using a personal router connected to the cablemodem, and both the router and the cablemodem are on a UPS. However, the UPS is old and I'm not sure if it's providing enough power to the cablemodem during these events, or if the cablemodem is losing power. I've checked the router itself and the uptime clearly shows that it is retaining power, but I've seen notes about the WAN port being unplugged that suggest the cablemodem may be losing power. Is there a way for me to access a web interface for the cablemodem? According to the Xfinity page, my cablemodem is a Cisco DPC3000. I've tried connecting to 192.168.100.1, but I'm unable to access that.
Confirm that make and model number by physically looking at the label on the modem. The DPC3000 is not on their approved / compatible modem list.
I just did, it's accurate. I'll note that I'm renting it from them, it's not something we own, we've just had it for ages at this point... something like 6-7+ years.
O/k, it must be grandfathered in then. It was supported years ago as I had one. I ditched it for a number of reasons including the same problem you are having. After a new firmware push, I could no longer access the user-interface pages.