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rajak87
Visitor

Periodic high ping latency on CG3000DCR

Hi,


I moved a couple weeks ago and had my Comcast business internet line transfered to my new home. I went from an SMC modem/router box to a newer NetGear CG3000DCR device during the transition. I am noticing issues very often with my internet connection. When streaming any type of content, there are very frequent blips where streaming freezes. Anything that requires a true live connection is difficult (streaming, gaming, remoting for work, etc).

 

To isolate the problem, I disconnected all hardware connected to my Netgear device except for one computer. Ran a ping test to the netgear box (10.1.10.1), google.com, and espn.com. Roughly every 50seconds, the ping latency jumps very high (sometimes > 3000ms). I ran the same test with another machine and saw the same results so this is not a HW Issue on my machine's side.

 

Result pinging the netgear box:.
ping 10.1.10.1 -t
Reply from 10.1.10.1: bytes=32 time=1ms TTL=64
Reply from 10.1.10.1: bytes=32 time=1ms TTL=64
Reply from 10.1.10.1: bytes=32 time=1691ms TTL=64
Reply from 10.1.10.1: bytes=32 time=1ms TTL=64
Reply from 10.1.10.1: bytes=32 time=1ms TTL=64
...<intentionally truncated numerous normal pings>
Reply from 10.1.10.1: bytes=32 time=1ms TTL=64
Reply from 10.1.10.1: bytes=32 time=1ms TTL=64
Reply from 10.1.10.1: bytes=32 time=1831ms TTL=64
Reply from 10.1.10.1: bytes=32 time=1ms TTL=64
Reply from 10.1.10.1: bytes=32 time<1ms TTL=64
...<intentionally truncated numerous normal pings>
Reply from 10.1.10.1: bytes=32 time=1ms TTL=64
Reply from 10.1.10.1: bytes=32 time=2833ms TTL=64
Reply from 10.1.10.1: bytes=32 time=1ms TTL=64

 

Sometimes the high latency ping is 400-800ms instead, but this is still very high and should not be occurring so regularly as it is. The ping tests to google.com and espn.com were also similar to the above, but not important since connection to the Netgear box itself is failing here.

 

Below is a picture of relevant debug details from the web admin of the Netgear box. I blacked out the serial number as I wasn't sure if it was intended to be private or not.

 

ComcastDebugInfo.png

 

I have tried power cycling the device and machines to no avail. Please let me know how I can address this. Thanks in advance for your help.

 

Side note:

Worth noting that for a client at work, I ran into this exact same issue with a Comcast connection at their site. They were using the same netgear box and ultimately it had to be swapped by a Comcast technician. 

 

Thanks,

 Raja

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11 REPLIES 11
Justin
New Member

Re: Periodic high ping latency on CG3000DCR

Hey,

 

I'd just like to add (for future people who find this by searching) that I'm having the exact same issue (occasional high ping times when pinging the gateway, model CG3000DCR, which is a Netgear based model). I have a tech coming out in a week to swap it out. It's extremely unfortunate that Comcast made such an impressively large mistake putting out this Gateway without more testing. Just searching the internet for "Comcast CG3000DCR" reveals that it really REALLY wasn't ready for primetime.

 

I'd also like to add, however, that I'm hoping Comcast will have this fixed in the near future, so it may not be the best solution to call up phone support and demand to have your gateway swapped out.

 

That having been said, the only other things I can think of that'll cause a gateway to react like this are if it's running above peak capability (these Netgears are BEEFY, so I seriously doubt that) or a bad piece somewhere in your physical layer (Ethernet cables, routers, switches, etc) between the pinging computer and the gateway.

 

At this point, however, I'm plugged directly into the gateway and pinging its IP address directly and it's giving me the same issues that have already been discussed by the original poster.

 

tl;dr: The CG3000DCR is a very capable piece of hardware, but the firmware wasn't ready for a wide spread roll out into businesses.

 

~Justin

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rajak87
Visitor

Re: Periodic high ping latency on CG3000DCR

The issue lasted several days for me and then _seemed_ to go away. But since yesterday I'm facing the exact same issue again.

 

@Comcast: This is an urgent matter as I'm often unable to work because of this. Is it possible to escalate this into a service request? It would be easier for me so I don't have to re-explain the issue over the phone. If I don't hear anything, I'll try calling sometime tomorrow. Thanks in advance for your help.

 

@Justin:

Thx for the reply. I've seen numerous other reports of similar issues as well. There is another thread specifically about this device here as well:

http://forums.businesshelp.comcast.com/t5/Equipment-Modems-Gateways/COMCAST-Serious-Problems-with-al...

 

 

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Community Manager
Community Manager

Re: Periodic high ping latency on CG3000DCR

HI rajak87.  We have reached out to our Tier 2 Team to assist in resolution.  Please let us know if you have not been contacted.

 

Thank You

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chow11
New Member

Re: Periodic high ping latency on CG3000DCR

I have this issue with a recent modem swap as part of a speed upgrade.  When power cycling the modem, the issue will dissappear for a day or 3 but then when I start seeing hiccups in the internet service, we have to just keep unplgging the modem every day or two.

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Forum Contributor

Re: Periodic high ping latency on CG3000DCR

These problems are generally caused by memory leaks in the modem firmware.

 

The best thing you can do is turn OFF the firewalling and NAT in the modem and buy yourself a DECENT router - preferably one with the capability of running dd-wrt or openwrt which are replacement firmwares that are far, far superior to the dreck the factory puts out.

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rajak87
Visitor

Re: Periodic high ping latency on CG3000DCR

Just wanted to report back..

 

I'm still seeing my original problem. When I called Comcast Support a few months ago, they scheduled a tech visit. However, the tech called me beforehand and said that this was a problem on their side and that lots of people had been complaining about it for months. I asked him if he could swap my device back to the old SMC one and he claimed the problem would still persist. Cancelled the visit as he essentially stated it wasn't a problem on my end. He noted my contact info and said he'd call once they resolve it on their side.

 

Now, 3 months later, I've heard nothing and still see the issue every day. I still suspect a firmware issue on the Netgear devices as tmittelstaedt alluded to above. I will call again tomorrow to request a device swap back to the SMC again. We had the same issue in another office and switching to the SMC seemed to resolve matters.

 

I'm not sure why this isn't treated with higher priority on Comcast's side if it truly is affecting so many people as the tech mentioned. For normal internet browsing, you might just notice longer load times randomly which is survivable. However, any use case requiring a 'constant' connection is unbearable. Due to the ping spikes, calls over Vonage have 'gaps' in audio,  online gaming sessions get disconnected or have lag spikes, etc.

 

Will report back after calling Comcast again tomorrow.

 

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Community Manager
Community Manager

Re: Periodic high ping latency on CG3000DCR

Hello rajak87,

 

Thank you for updating the community, we appreciate it!

 

 

 

 

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leehopemcc
New Contributor

Re: Periodic high ping latency on CG3000DCR

I have had the same high response time for several months through 3 replacement modems......

Have there been any solutions yet?

 

This makes it imposible to use VOIP phones....

 

Comcast, do you have anything new?

 

Thanks,

Lee

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rajak87
Visitor

Re: Periodic high ping latency on CG3000DCR

Just wanted to provide an update to everyone.

 

I called Comcast Business Support on Wednesday 2/26/2014 and explained the issue I'm seeing from my original post. I requested a device swap to the SMC Gateway. The CSR immediately agreed which is an indication to me that they are aware of the problem internally. I didn't even have to go through any tests over the phone or the usual power cycle routine. A service visit was scheduled as early as possible which was 2 days later on 2/28/2014 (today). 

 

I stayed home from work to be available for the service visit. This morning as scheduled, two Comcast workers arrived to my house. They told me that they were unable to provide an SMC Gateway as they no longer have them. They said they're aware of the issue and that there would be a firmware update soon to resolve it. I explained that I've been having this issue for 5-6 months and that I was told the same thing several months ago. They put me on the phone with someone higher up on the business service side. He told me there were indeed issues (related to packet prioritization) and that he just got an email yesterday about a new firmware update. They're pushing it out slowly to different regional areas to test it. He said it could take 2-3 weeks to get to me and to call again after that if I'm still having problems.

 

The firmware version he said was being pushed out is v1.34.02. I'm currently on v1.33.03.

 

As I have static IPs, there were no other options for me. Comcast doesn't allow me to buy my own modem so I'm stuck. To reiterate, I was essentially told I have no options to resolve this issue for my existing service besides waiting the 2-3 weeks.

 

One alternative I asked about would be getting rid of my static IPs and then buying my own modem. The tech told me this would be okay. This is something I'll consider but this would require a lot of adjustments and time investment on my side.

 

All that said, the whole situation is pretty ridiculous from a business perspective. I'm very skeptical that a fix will arrive. After all, I was told the same thing before and months later I still continue to have the same problem. 

 

I would be interested and thankful if others who are having this problem could post here just to bring more attention to the issue. 

 

Thanks,

 Raja

Trusted Forum Contributor

Re: Periodic high ping latency on CG3000DCR

FWIW, this is exactly the kind of thing I was seeing with this modem & 5 static IPs - every 5-10 packets are highly delayed, and not just pings, but any kind of traffic. In my case, I was actually dropping packets completely - I would get a dropped packet, then the next one would have a 1.5-2 second response time, then back to normal for another 10 packets or so.

 

And I was told by CSR's that multiple, successive firmware updates were coming to fix the problem - none of them did. I believe I went from 1.33.01, to 1.33.02, to 1.33.03 with no fix. I ended up being lucky enough to have a truck roll where the tech had 1 remaining SMCD3G device, and he said that that was the last of the stock they had in my area. Going back to this modem immediately resolved this issue, so it seems a specific problem to the Netgear. From my reseraching, it seems like it's also only a problem when the Netgear has a static IP (or multiple) loaded into it.

 

For now, insist on an SMC! And hopefully Comcast/Netgear can figure this out; hardware-wise, the Netgear is a better capable modem, in at least that it can bond 8 channels on the Downstream versus the SMC's 4.

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nathandouglas
Occasional Visitor

Re: Periodic high ping latency on CG3000DCR

I'm having the same experience, pretty much.  Very high ping latencies (1.8-2 seconds in some cases), very high drop rate (up to 80%), and needing to restart the thing every couple of hours.  Not particularly interested in paying well over $100 a month to be a beta tester.

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