SURFboard SB6121
Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem

The Motorola SURFboard SB6121 router has No WiFi, 1 N/A ETH-ports and 0 USB-ports.
It is also known as the Motorola Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem.

Quick links:
Default password/Login



SURFboard SB6121 router specifications (specs)

System specs
CPU: n/a
RAM: 32 MiB
Flash: 8 MiB
Custom firmwares: None
Connectivity
WiFi: No ()
WiFi bands: n/a
WiFi throughput: n/a
WAN: None
ETH: 1 x N/A port
USB-ports: 0

Motorola SURFboard review (quick overview)

Here is the quick comparison of how the Motorola SURFboard compares to other routers on our site:

Average 31/100
Editor 88/100
WiFi 2/100
Hardware 3/100
Current price Find best price

For a full list of routers and how they compare to the SURFboard SB6121, check the Router Buying Guide which will help you buy the most price-competitive router.

Hard reset instructions for Motorola SURFboard SB6121

If your SURFboard SB6121 router is not working as it should, dropping connections or not being responsive, you should first do a reset of the router to see if the problems persist. Other scenarios where you might want to reset your router is if you've forgotten the password or misconfigured it and can't get access anymore.
Your can reset your Motorola SURFboard SB6121 in the following way(s):

The 30-30-30 reset

There are no specific instructions for this model yet, but you can always do the 30-30-30 reset as follows:
  1. When router is powered on, press the reset button and hold for 30 seconds. (Use a paper clip or something sharp)
  2. While holding the reset button pressed, unplug the power of the router and hold the reset button for 30 seconds
  3. While still holding the reset button down, turn on the power to the unit again and hold for another 30 seconds.

This process usually works for resetting any router to it's factory setting. If that doesn't work be sure to check out the questions and answers incase someone else has had similar problems resetting their router.

Note: It is worth reading more about how to reset routers with the 30 30 30 reset and what the risks and considerations are when resetting your router this way, instead of just rebooting it.


Default factory settings for Motorola SURFboard SB6121

If you have performed a reset of your SURFboard SB6121 device or not changed the defaults, you should be able to access it with the following settings:

Default Gateway IP: 192.168.100.1 Motorola login instructions
Default subnet mask: 255.255.255.0
Default DNS server: 192.168.100.1
Note: If you are using the default settings you should change them to increase security and prevent unathorized access to your network.

SURFboard SB6121 Firmwares

Staying up to date with the latest firmware is a good idea to keep your router even more secure from various security flaws.
If you want to squeeze a little bit of extra functionality out of your router, consider flashing an open-source firmware like dd-wrt, openWRT or LEDE. Flashing a custom ROM can greatly increase the stability and functionality of your old router.
Following are the firmwares that we have identified existing for the Motorola SURFboard SB6121:

Motorola stock firmware for the SURFboard SB6121

Stock firmwares for the SURFboard SB6121 are available under the download section on the modem's support page. You can also refer to the router's manual for instructions on how to upgrade the firmware.




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