Link between SB6120 and RT-N66U defaults to 100BASE-T

[ConnYack]

I recently purchased an ASUS RT-N66U. I have it connected to a Moto SB6120. Out of the box the Router had 3.0.0.4.220 firmware. I pushed .246 to it and now I have a problem. The link between the modem and the router is stuck at 100BASE-T. I gather this from the fact that the modem link light is blinking orange. Orange = 100BASE-T, Blue = 1000BASE-T. I talked to ASUS support for 45 minutes and no cookie. My internet speeds are phenomenal; I only pay for 35Mbps down. I get full speeds out to about 150 feet. I just want the modem - router link to be gigabit because it's supposed to be. Anybody have a clue what is going on? Feel free to school me if my understanding is off.

 

[Raptor]

I recently purchased an ASUS RT-N66U. I have it connected to a Moto SB6120. Out of the box the Router had 3.0.0.4.220 firmware. I pushed .246 to it and now I have a problem. The link between the modem and the router is stuck at 100BASE-T. I gather this from the fact that the modem link light is blinking orange. Orange = 100BASE-T, Blue = 1000BASE-T. I talked to ASUS support for 45 minutes and no cookie. My internet speeds are phenomenal; I only pay for 35Mbps down. I get full speeds out to about 150 feet. I just want the modem - router link to be gigabit because it's supposed to be. Anybody have a clue what is going on? Feel free to school me if my understanding is off.

I also have the SB6120 and RT-N66U. The SB6120 link light is Blue. My first guess would be to check the Ethernet cable. I use Cat-6, Cat-5e will work too. Anything Cat-5 and below will drop back to 100BASE-T. Some times the quality of the cable assembly is poor and will cause a drop to a lower speed.

 

[ConnYack]

I also have the SB6120 and RT-N66U. The SB6120 link light is Blue. My first guess would be to check the Ethernet cable. I use Cat-6, Cat-5e will work too. Anything Cat-5 and below will drop back to 100BASE-T. Some times the quality of the cable assembly is poor and will cause a drop to a lower speed.

I have a 4ft piece of Cat 6A connecting the two. I get the same Orange light with other cables.

 

[AnthonyArmato]

You already have a thread on this: http://forums.smallnetbuilder.com/showthread.php?p=51164#post51164

 

[Raptor]

I have a 4ft piece of Cat 6A connecting the two. I get the same Orange light with other cables.

I would try different cables. Try the one the comes with the RT-N66U router. Also check to see what firmware your SB6120 is running. Versions before SB612X-1.0.5.2-SCM01-NOSH Boot Version: PSPU-Boot 1.0.0.4m1 were a little flaky. To find the firmware version go to 192.168.100.1 and look under help. If its out of date you can call your cable company and have them push an firmware update to your modem.

 

[ConnYack]

I would try different cables. Try the one the comes with the RT-N66U router. Also check to see what firmware your SB6120 is running. Versions before SB612X-1.0.5.2-SCM01-NOSH Boot Version: PSPU-Boot 1.0.0.4m1 were a little flaky. To find the firmware version go to 192.168.100.1 and look under help. If its out of date you can call your cable company and have them push an firmware update to your modem.

I checked my firmware, it's running SB_KOMODO-1.0.6.6-SCM00-NOSH and Boot Version PSPU-Boot 1.0.0.4m1.

 

[RMerlin]

Some ISPs like to muck with their customer's modem settings. For instance, my own ISP remotely disables all web interfaces in their modems Maybe they remotely disable gigabit support for enhanced stability?

I'd take a look through your modem's webui to see if there's anything related to the LAN interface speed.

 

[ConnYack]

Some ISPs like to muck with their customer's modem settings. For instance, my own ISP remotely disables all web interfaces in their modems Maybe they remotely disable gigabit support for enhanced stability?

I'd take a look through your modem's webui to see if there's anything related to the LAN interface speed.

I have a RT-N66U with 3.0.0.4.246. Dug and dug and dug thorugh the UI. Looked at the system logs and couldn't see anything interesting. What registers between the modem and the router when a WAN link is created? Is there a handshake system of some sort? Why would the modem think the WAN link is 100 MB/s? Does the router tell the modem what it is? Is it a signal strength test of some kind? I'm blaming it on the router due to the fact that the modem registers a gigabit connection with other pieces of hardware that I have. Just no cookie for the $160 router!

 

[jdabbs]

Ethernet performs auto-negotiation between endpoints to determine link speed. Link speed is determined by device capability and cabling.

 

[ConnYack]

Ethernet performs auto-negotiation between endpoints to determine link speed. Link speed is determined by device capability and cabling.

So here is a tidbit, when I first took it out of the box, it had .220. I tried to push .246 to it from a USB drive and it wouldn't see it. So I pushed it from my connected laptop; it went to 100% refreshed and the update wasn't there. So next I had it try checking the ASUS server and it went to 100% and hanged. I power-cycled the router and walla! It showed .246. But now my link light was blinking 100BASE-T. But here is the thing, when I first plugged it in out of the box, it had a gigabit WAN connection! After the last firmware push it has been stuck at 100. And nothing will shake it (haven't tried physically shaking it yet...maybe I should). But I digress. I might try throwing it at a wall and see if that fixes it.

 

[jdabbs]

I think you've narrowed it down to two possibilities:

1) Many devices have the ability to configure the link speed of their ports. This configuration option may not be accessible to the end user. Since this option is not expected to ever be changed, a firmware update that modifies this setting is not likely to be restored in subsequent updates. In such a scenario, your best hope is to reload with as many different firmwares as possible to get a default value back in place.

2) You've tested with a known good cable and device, and the router hardware is defective. Why after the firmware update? Could be a number of things, maybe the modem or router fell when you power cycled it, putting physical stress on the jack. Maybe the device was borderline faulty, and some time was all it took to degrade to the point of no return. Maybe a storm surge zapped it months ago, and you just now noticed the lower link speed since the firmware upgrade brought attention to the modem. Who knows.

A RMA would address both issues.