Another CenturyLink Fiber Speed Issue (AC3100)

[Gambinesh]

Hello All,

I am trying to find information to help me troubleshoot my current network speed. I have Centrify Link gigabit fiber. When the installer came out 6 months ago he brought their modem. Speed tests showed it getting around 950 mbs. I read up on my specific router, Asus AC3100, and found that I didnt need the CenturyLink modem. I was already running merlin's firmware (380.68_4) so plugging in the PPPOE and vtagging info was easy enough to get me connected. I thought I was up and running well and sent the Century Link modem back so that they didn't charge me for it. However, now I am seeing that I am getting 500mbs over Ethernet if I am lucky. Sometimes it is less. Depending on which speed test that I use, it fluctuates. I have been relying on google fiber speed test and the dslreports gigabit test. They are showing around 500 most of the time.

I spent a lot of time reading up on this. I have checked that HW Acceleration is enabled. I made sure QOS is disabled. All filtering is disabled. URL filtering is disabled. Everything is basically vanilla. I even reinstalled the firmware and did a factory reset and set everything up again to find the same results. The system that I am testing with is a custom built PC. Fresh install of windows 10. 16gb ram. ASRock Fatal1ty mITX. i7 6700k. etc. I also have read that the router hardware can be a bottleneck. When running speed tests, the firmware shows core 1 at 75%. Core 2 at 1%, and ram at 135 used. I dont think its getting too bogged down. I even tied setting up ipv6 just for giggles but that didnt change a thing. I have no USB attachments on the router. AI cloud is off. Sys log shows no issues, jsut DHCP requests which are normal. I set the PC up with a static IP just to check. No changes.

At this point I have tried everything that I can find in the forums so I thought I would see if anyone else had any ideas.

 

[Zolpho]

I had a similar problem recently with a RT-AC88U (380.68_4), but happened with stock firmware as well.
My fiber media converter is a ZyXEL CTS CVT-3512 SC, which was in "bridge mode", no VID configured.
Then I configured my AC88U to do PPPoE with VID = 11 and my speed tests showed ~400-500 Mbit.

So I configured my media converter to do vtagging and removed the VID option from my Asus.
My speed tests now are around 820-870 Mbit.

 

[Gambinesh]

Interesting, I dont have a fiber media converter. My PPPOE and VID options are all in the AC3100. Is a separate box really needed to get full speed?

 

[Gambinesh]

Well, as an update, I took the following steps:

Factory reset
Shut off
Unplug
Turn on in recovery
Install 382.1 Beta
Factory reset
Internet Setup
Speed test = 600ish.

I did notice that the CPU load is much less with the beta firmware. Im at core 1 32% and core 2 1% during speed tests instead of the 75% that I did have.

Im going to run the beta firmware for a while and see how it goes. Im still annoyed that I cant seem to get at least 900 which the crap Century Link combo could do. If anyone has any other thoughts, please let me know.

 

[dnuzum]

I've got the 3100. Have had the issue pop up no matter what the firmware. Usually what fixes it for me is a unplugging 3100, then rebooting the ONT. I'm in Seattle, FYI. CLink recommends *not* rebooting the ONT yourself as the only way to do so is unplugging at the power point and that can be really hard on fiber supposedly so a call-in is what they recommend. I haven't broken it yet, but they do say if they see a lot of power cycles, they'll charge you to replace it.

After awhile it drops down to the 500-600 range and I just reboot stuff seems to do the trick. I really think it's just a case of them prioritizing support for their own crappy hardware. I spoke with a network tech at length and gave him remote access. He said everything was setup perfectly like most of the same threads you probably used for setup.

 

[Gambinesh]

Anything I need to know about rebooting the ONT? Can they do it remotely without me pulling the plug? If I un plug and plug back in does it come up on its own or do I need to do something with it?

 

[dnuzum]

You can reboot it without doing anything. Just a simple unplug and back in. I typically unplug 3100, then ONT unplug. Wait like 5 minutes just to get clear on their side. Then ONT back, then 3100 back. I typically turn everything off wifi and other hardlined devices. Just use my primary rig as they will only accept speed complaints with a regular speedtest from a single machine. Somehow having other stuff plugged in just really bogs the tests down. Doesn't make much sense, but it is what it is. Once it's all back up, I do a speedtest and it's within their acceptable parameters 750-800 minimum. Even with their hardware I never hit 1000. Was typically 900-950. After a reboot I'm typically good for a couple weeks at a minimum with my own hardware.

 

[Gambinesh]

Alright, well shutting off the wireless and disconnecting all Ethernet but my pc got me to 750 which is an improvement. I'd like to know why a few wireless clients and a few wired clients cause such a big decrease...

Anyways, I'm rebooting the ONT now to see if that helps. I'd like to see them try to charge me to replace stuff from reboots when their ONT power box has a reset button and the tech who installed it said if there was ever and issue after a power bump to reset it. I'll take that little wiggle room and run with it.

 

[dnuzum]

Oh yea, it would be tough to prove it was your fault. Could just say it was a power outage, etc. My reset button got "deactivated" on install. Some sort of policy I guess. Argued with the tech and the hardware desk, but I guess it's worse to hit that than just unplugging it for a time. Probably quick jolts worse than off and on for 5 minutes. /shrug

But, yea, it's crazy how much it changes 1 device versus multiple. Maybe playing with QoS settings could help that? Haven't dug around too much as 500 up/down is still plenty sufficient and when I need the full bandwidth can just toggle things on and off. Still better than the monthly fee or $100-$120 outright for their hardware.

 

[Gambinesh]

Well rebooting the ONT got me the same 750 with no other clients. I have a tech coming out tomorrow. I guess I'll let him try some testing. Not holding my breath.

 

[dnuzum]

Yea, it's worth a shot. I've been considering pushing for it as well. Just been too busy with work. Let us know! Maybe they can take a look at how it's interfacing and tinker around. ^__^

 

[Gambinesh]

Ill let you know if I get anywhere. 750 is better than the 500 I was getting. I plugged the clients all back in and i'm still getting 750 now. If you have any other thoughts, let me know!

Thanks for the help!!!