Strange recurring issue with Rogers Technicolor CGM4140COM (Ignite 1 gigabit)

[NorthGraves]

Setup:

Rogers Technicolor CGM4140COM in bridge mode

Ubiquiti EdgeRouter Lite (ERL-3) router behind it

Kanata (Ottawa), ON

1 gigabit/30 megabit package + Ignite TV channels

Speedtest:

946 down/31 up, no issues

Issue:

Once every 1 to 1.5 weeks the speed doesn't exceed (any speedtest, consistently) 650-680 megabit down.

Complete power off to both cable modem and router for 5 min - no impact, still (!) 650-680 megabit down when all powered up and running.

Router restart - no impact.

Cable modem restart - no impact.

Troubleshooting (the weird part):

Change the cable modem from bridge to gateway mode (90 sec).

Restart the cable modem (3-4 min).

Change the cable modem back from gateway to bridge mode (90 sec).

Speed test - back to 946/31:-).

The best uneducated explanation I can think of is the cable modem "syncs up" with Rogers' servers at a lower speed for some reason, the power off/on doesn't change that synced up speed, but this bridge-->gateway-->restart-->bridge sequence somehow forces to re-negotiate the speed back to the maximum 946 down.

No idea what to do about it, and even if anything can be done about it...

***EDITED LABELS***

[-G-]

@NorthGraves  This exact same problem has been previously reported by another user.  Trying to find that post now...

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Found it!  @KoN1  reported the same problem here: https://communityforums.rogers.com/t5/Ignite-TV/Using-the-Ignite-TV-Modem-Gateway-in-Bridge-Mode/m-p...

You also both happen to be using Ubiquiti routers that run EdgeOS.  When your Internet suddenly slows down, what happens if you were to unplug your router, then connect a computer to the XB6 while it is still in bridge mode and perform a speed test?  Do you see the same results?

[Taab]

I have this exact same issue running ubiquiti routers and the technicolor in bridge mode. 

[NorthGraves]

Thanks, interesting, I will try, but what is inexplicable to me is why a complete power off of both devices doesn't change anything....but this weird sequence on the cable modem does...

[-G-]

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@NorthGraves wrote:

Thanks, interesting, I will try, but what is inexplicable to me is why a complete power off of both devices doesn't change anything....but this weird sequence on the cable modem does...

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I have no idea what's going on here or what could be causing the slowdown.  All speed tests have been performed through the Ubiquiti router.  Since power-cycling the XB6 does not fix the problem, it may or may not be at fault.  That's why I thought it would be interesting to perform a direct speed test while the XB6 is in a possibly bad state.

Another thing that happens (from the router's perspective) when changing the XB6 from gateway to bridge mode is that the addressing on the WAN interface changes from 10.0.0.0/24 to a public IP address.  I don't see why that should change anything on either the XB6 or the router... unless the router has QoS enabled and/or is doing some rate limiting in which case, changing the IP addressing on the interface may cause it to reset its local state.

[Taab]

The thing is I was getting gigabit speeds with CODA Modem. I have hardware offloading enabled and QoS disable (Ubiquiti Features) and the max speed I get is 600 Mbps when bridging the technicolor modem. 

Can anyone from Rogers speak on this? 

[RogersGordon]

We're able to replicate this in the lab with a direct connection in bridge mode after a reboot and have escalated to the vendor. We haven't received any updates yet but we can share as they become available. 

[RogersGordon]

We've received a build that includes a BCM fix for this issue and we're testing it now. I'll update this thread once it's been validated. 

[-G-]

@RogersGordon  Thanks very much to you and to the team for confirming the bug and for keeping us up to date on progress towards a fix.  We really appreciate it!

[RogersGordon]

Good news! We've been unable to replicate the degraded throughput in bridge mode issue on the new firmware. This release is already in the deployment pipeline so gateways should be updated over the next couple of weeks.

[Taab]

Couple of weeks? . . 

[NorthGraves]

What is the version of the updated firmware?

Currently showing:

eMTA & DOCSIS Software Version:Prod_18.1_d31 & Prod_18.1

Software Image Name:CGM4140COM_4.0p6s3_PROD_sey

Advanced Services:CGM4140COM

Packet Cable:2.0

[Taab]

@NorthGraves Hey did the issue get fixed for you after the firmware update? 

[NorthGraves]

Testing, will report later.

[NorthGraves]

Same behaviour, unfoirtunately, once every X days.

Ran a couple of tests right now, clearly shows 650M down.

The sequence (bridge --> gateway --> restart the modem --> bridge) fixes this back to 945M down.

[Taab]

Jesus, it's the same for me as well.

[Taab]

Just got another update. 

Software Image Name: CGM4140COM_3.14p10s5_PROD_sey

Now I'm barely hitting 600 Mbps. I hover around 550-600 Mbps. I love getting the speeds I pay for. 

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@Taab wrote:

Just got another update. 

Software Image Name: CGM4140COM_3.14p10s5_PROD_sey

Now I'm barely hitting 600 Mbps. I hover around 550-600 Mbps. I love getting the speeds I pay for. 

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I am running the same version as you, which I am pretty sure is actually a downgrade from what I had before.

According to @RogersTony , we should now all be on version 4.0p9s1 although, clearly, this is not the case.  Perhaps there was a misunderstanding and they are really only just getting ready to roll that version out.  Hopefully they will get this figured out soon.

[Gagee1]

I am experiencing the same issue as well and I am still on Software  version CGM4140COM_3.14p10s5_PROD_sey.  Are you still on this version as well. I wonder when they will be pushing the new firmware. 

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@Gagee1 wrote:

I am experiencing the same issue as well and I am still on Software  version CGM4140COM_3.14p10s5_PROD_sey.  Are you still on this version as well. I wonder when they will be pushing the new firmware. 

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My XB6 has not been updated yet either.  Updates are staged, starting with a small number of people at first.  If no problems or regressions are found during the initial roll-out, more and more people will get updated in batches over time.

It looks like they have already started the process.  Maybe we will get the new firmware tomorrow.  Maybe Rogers is tracking new problems and has temporarily halted the roll-out.