Rt-N66U IPv6 Slow

[Gapmn]

Okay, IPv6 is up and running on my RT-N66U 374.40 Merlin. One glitch...down and upload speeds are very slow at 1/1, normally 40/5. IPv6 connections slow, while Ipv4 still at 40/5. IPv6 test websites say everything is working normally. This is on a Centrylink PPPoE VDSL2 connection. Any ideas??

 

[jlake]

What MTU are you using for 6rd? Which ones have you tried?

What I ended up doing was taking my modem out of bridge mode to see what settings AT&T used for 6rd. In my case, I had them all correct, but it never hurts to double check.

So if you temporarily take your century link modem out of bridge mode, you should be able to access the modem's settings and see what century link uses for 6rd settings and make sure you're using the correct settings on asus.

Also, have you configured the LAN too?

What is the make and model of your modem?

 

[Gapmn]

I am using Centurylink's settings off their website. MTU 1472, Modem q1000z

 

[jlake]

Is this the speed test you're using?

http://speedtest.comcast.net

 

[Gapmn]

Is this the speed test you're using?

http://speedtest.comcast.net

Yes that was one of them.

 

[jlake]

Yes that was one of them.

I don't know then. I flashed the same firmware you're using on the same router, and setup AT&T adsl 6rd on the N66u. Works fine. IPv6 speed is same as ipv4. Maybe it's because you're using vdsl. I'm using adsl. Try giving centurylink a call and see if they'll help you.

And give those other MTUs a try like 1280.

Make sure the instructions you're using from centurylink are for VDSL if you have VDSL. Not sure if aDSL and VDSL 6rd settings are the same. Probably are. But it would be worth checking.

I'm not having any problem with AT&T adsl 6rd using Merlin .40 on RT-N66U. My modem is in bridge mode and running PPPoE on the N66U.

 

[RMerlin]

Not sure how IPv6 is implemented for you, but I would keep in mind the fact that PPPoE (which is often used with DSL) has an 8 bytes overhead. Try lowering your MTU by 8 (or even 32 bytes to be safe) just for testing purposes.

 

[Gapmn]

Okay, thanks. I tried the MTU of 1280, no difference. I will give CL a try. It could be a ADSL/VDSL issue.

 

[Gapmn]

Centurylink said they have not received much training on Ipv6 yet. They thought the ADSL and VDSL2 setting where the same. Again, even though CL list the parameters on their website, it is not officially supported yet. Here are my IPV6 settings. It passes all the tests when checked on any of the IPV6 testing websites, it's just has extremely slow down and up speeds. IPV4 40/5, IPV6 .9/1.3

 

[TheOldMan]

I have Centurylink ipv6 6rd. I assume you have ipv4 dhcp? I have a static ipv4 and dynamic ipv6 however I am able to manipulate via godaddy to get a static ipv6. My speed test on both ipv4 and ipv6 is around 35 mbps down and 18 mbps up. I'm using merlin's .40 release. Your ipv6 settings are similar to mine. Did you do a firmware reset and re-do ipv6? I have a n66u router and ipv6 has performed well before merlin implemented the ipv6 firewall which works flawlessly.

You may want to dump Centurylink's ipv6 dns. I use google's ipv6 dns. 2001:4860:4860::8888 and 2001:4860:4860::8844. You can also try opendns ipv6. 2620:0:ccc::2 and 2620:0:ccd::2. Try these and see if they help?

 

[Gapmn]

I reset the NVRAM after the 374.40 F/W update, then I entered the IPV6 settings.

 

[TheOldMan]

I had problems using Centurylink's dns servers. Changing to Google or OpenDNS seems to help greatly. I have complained directly to Centurylink that their DNS servers are subpar. They say they are working to fix the servers. I told them good luck doing that. I assume you have set them modem into transparent bridge? Set up the router to PPPOE? Dynamically get ipv4 address? Change ipv4 dns to Google's 8.8.8.8 and 8.8.4.4? Your router should function good if you don't use Centurylink's dns. Did you change the ipv6 dns and retest?

 

[Gapmn]

Yes to all except I am not using Google DNS for ipv4 or ipv6

 

[TheOldMan]

This is what my speedtest from Comcast looks like...

 

[Gapmn]

I guess I could try the Google IPV6 DNS server

 

[Gapmn]

No different on google and opendns ipv6 servers :-(

 

[TheOldMan]

Did you try to reflash the firmware? Then do a factory reset? Then re-input your settings? If it does not help, I would suggest that you contact ASUS for a replacement.

 

[Gapmn]

It doesn't seem like a hardware issue to me.

 

[jlake]

It doesn't seem like a hardware issue to me.

I also highly doubt it's a hardware issue. My theory is century link has you capped on ipv6 because they're too cheap to build up their network for IPv6 for home users at this time. They probably can't justify the cost at this point.

If you're really wanting to figure it out, my advice would be to fight your way through level 1 tech support and see if you can speak with one of their level 2 or 3 support people. You may have to wait on hold or call back multiple times to get someone.

 

[TheOldMan]

I have never been capped at ipv6 from Centurylink. I have been using ipv6 for 3 years now. You can get an ipv6 static address using Hurricane Electric, sixxs.net, or godaddy. I prefer godaddy using the spf records for ipv4 and ipv6. Everything is working awesomely my end. I got to thank R Merlin for doing an awesome job.

Godaddy only has ipv4 glue records. No ipv6 glue records so you need spf descriptions for your static address. There is a trick to get the static address if you figure out how Centurylink does it's ipv6 pool. It does work good. I learned quite a bit using Hurricane Electric but they don't let you use your full allotted up/down internet speed. With godaddy and spf you get the speeds you paid for.