Double your speed double your fun

I was at one of my in-laws neighbors homes the other day, he needed some help setting up Rabbit.TV and his Chromecast. I had never heard of Rabbit.TV, while it is cheap, $10 for the year, I found it very hokey and very difficult to navigate. Plus I believe it just links you to all the free content, but places it all in one convenient spot – I don’t know and not the point.

When I was all finished he asked if I wanted an extra cable modem he had. He had been mailed the modem in error or ended up not needing it after he bought it, I can’t remember which. I hesitated at first as I really need to stop collecting ewaste, but I took it and I am glad I did. I looked it up when I got home, nothing fancy just a Motorola SB6141. I was using a Ubee DDM3513 at the time. I originally has some Motorola Dinosaur but it had died, the Ubee is what was given to us in its stead. I haven’t had a lot of issues but I do feel it was sluggish at time. Not evidence to back it up thats just the overall feeling I was given from The Family. They two modems are both DOCSIS 3.0 the difference is (that would make a difference) that the SB6141 can handle “channel bonding of up to eight downstream channels and four upstream channels” (up to 300 Mbps downstream, 100 Mbps upstream). The Ubee is 4/4 (up to 171Mbps downstream, 122Mbps upstream). I Googled the hell out of the Motorola for a few hours and I came up with a lot of posts and forum comments on the performance. Most people advertised they were getting a higher Mbps with the SB6141 than other modems for their current speed tier (hitting 12Mbps on a 6Mbps account for example). So I decided to swap the modems out.

It actually went very smoothly, on Comcast’s side. I connected the new modem (SB6141) in place of the Ubee and plugged my netbook directly into it. It connected to the net within about 3 minutes or so. When I transferred the modem to the server/router is when I hit a snag. My ClearOS box wouldn’t grab a new IP address from the modem. If I watched it closely I could see it get the local address, then drop it, then switch to the ISP public and then drop it 10 seconds later. Then I got to stare at the spinning loading logo forever. The netbook would grab it no problem every time. I power cycled the modem and the server/router many times, made no difference. I even tried cloning the MAC of the netbook on the server/router, it did take the clone but it made no difference either. What worked for me was to delete the ethernet card under “IP settings”. Mine is eth11 so I just deleted eth11 and then added it back in again. Voila it worked.

Speed tests ran from and speakeasy both report 12Mbps down, 1Mbps up. Prior to the modem switch I was only hitting 6.5Mbps, which is my speed tier cap. So 12Mbps on a 6Mbps speed tier – score, at least for now.

Update 10-22-2015: I have come to find an easier solution (other than not using Comcast and therefor not needing a cable modem). If you SSH into the box you can simply release and renew the IP of the ethernet port.

sudo dhclient -r your_nic followed by
sudo dhclient your_nic

For example my card is enp3s0 so I would type:

sudo dhclient -r enp3s0

That should release and renew the IP for you. I found this out after upgrading to ClearOS 7. The old trick of deleting and re-adding the NIC wasn’t working anymore. So it appears that it is not just Comcast and their cable modems, ClearOS has something to do with it.