C7000-100NAS randomly drops internet connection

[NCsandhills]

OK, I agree with your comments.

You have definitely determined that the "wi-fi router" part of the Cable Modem/Router is functioning just fine.  The Wi-Fi Router and LAN function independly from the modem; and since you can access (via Wi-Fi) the LAN devices from your PC  when the internet connection is lost - then it may be assumed that the Router-LAN part of the Cable Modem/Router is functioning OK - other than the modem connection and ISP signal. 

So, the issue might be one of the following: [1] periodic loss of the ISP cable signal to the modem - where the Cable Company or Line Connection at Fault; [2] modem drops the ISP signal connection to the router; [3] router drops the signal connection from the modem.  Both items [2] and [3] can be either physical hardware or internal software related.  It might even be temperature related - i.e., thermal buildup affecting physical connections (on the board or internal to a chip).  A longshot might be internet disruption when an incoming request or outgoing access is being denied due to a security or firewall setting within the Modem - in which case I would re-examine the devices attached to the LAN, and maybe disconnect them while you re-evaluate the Modem's operation (and internet ocnnection) without those devices "on-line".

One additional test (if not done before) would be to connect a PC to the LAN and see if the interent signal is maintained or lost.  If lost, then the Modem operation (and connection to the Router/LAN) is likely the issue - assuming the ISP signal is of consistent strength and quality.  If the internet connection is lost or intermittent, then the IPS signal is likely at fault (connection, quality, etc.).

This analysis assumes that the C7000 unit combined a "Cable Modem" with a "Router/LAN", with the two components operating "independly", but just on the same circuit board.  I believe you have narrowed the problem to either the ISP Signal or Modem operation, with a longshot issue with a LAN device.     

[junfitz]

Random Dropouts keep happening on my Netgear C7000. Has this been fixed yet? Looks like this problem has been happening for quite some time now. Did Netgear finally release a fix for this?  For an expensive modem/router, we expect so much more from this.

[8th_Day]

Comcast has been on this for the last several weeks/months and can't find anything.  However, their smallest test time is 5 minutes increments.  But I may have stumbled on the issues.  These statistics are for direct connect cable - computer to Router.

https://www.voipreview.org/speedtest

This site tests more than just upload and download speed.  i tests for Latency/Ping

We use MagicJack.  When we connect to a call, we loose the incoming voice for anywhere from 6 to 30 seconds.  We just keep talking, though that is hard to do when it is an answering machine or robo menu.  The tests explain what is happening.  But I don't know where to go with this.  Can't get to the right people at Comcast or Netgear.

When I ran this test the numbers in the beginning of the test were all over.  It looked like an EKG and then it is steady.  Something is happening at the beginning of the connection not only on the phone, but also when we go to other websites. 

This was 7 PM

This was 7:15 PM

This was 7:15 PM  This explains my MagicJack Phone issues

7:30 PM  IP Phone and Skype are OK

[NCsandhills]

is "UPnP" turned ON for both MagicJack and the Router? 

Do MagicJack's settings allow selecting Incoming Ports?  More than one?

These serttings will affect the performance of MagicJack, as well as other programs (Skype, etc.).

 Skype's "Tools" include these types of settings.  See "Tools/Options/Advanced/Connections".

[8th_Day]

We were told to turn UPnP off for security reasons by NETGEAR.  We have forwarded them manually, all of which are UDP. See below.

XXX = the dedicated ip address of Magic Jack

MagicJack Settings

	#	Service Name	External Port	External IP Address	Internal Port	Internal IP Address
1	MagicJackU	UDP: 5060	Any	UDP: 5060	192.168.1.XXX
2	MagicJackD	UDP: 5070	Any	UDP: 5070	192.168.1.XXX
3	MagicJack	UDP: 49152	Any	UDP: 49152	192.168.1.XXX
4	MagicJackRtp	UDP: 65525	Any	UDP: 65525	192.168.1.XXX

Here are my log enteries.

	Description		Count	Last Occurrence	Target	Source
These are two entries I can't isolate where they are coming from.
DHCP Request?  But from where? To Where?  None of these IP's are mine
	[DoS attack: IP packet w/MC or BC SRC addr] from 224.230.1.61, port 59834		1	Thu Apr 06 16:26:00 2017	65.52.108.76:443	224.230.1.61:59834
HEG US Inc. - have no idea why they would be trying to access through my router.
	[DoS attack: TCP- or UDP-based Port Scan] from 69.64.33.134, port 60688		1	Wed Apr 05 18:43:54 2017	My External IP:8686	69.64.33.134:60688

[JimPugilist]

did you find a solution to the problem...?? Same issue (timing sync failure) . Did reset, comcast checked----only wifi, ethernet works fine....

[BigDog2017]

The C7000 was the problem. Spent a lot of time narrowing down the issue with the help of Comcast. They were very helpful, the tech even gave me his personal cell and helped with some diagnositcs off the clock. I did the typical reset, did not help. Did the factory restore...did not help. The C7000 would actually drop the WAN connection every 20 minutes. Nothing in the logs would indicate trouble, other than the Sync issues I noted earlier. Ruled out every device on the network. My only option was to replace the C7000. Netgear never responded. I will try and return it later this week because its still under warranty. Additional proof that it was the C7000, I replaced it with a Netgear CM1000 and it has been rock solid since minute one...no other changes on the network. 

[JimPugilist]

it´s a shame, but thanks!!!!

[8th_Day]

Have not solved it yet.  Changed DNS from Comcast to another DNS.  There are fewer hits against the cable modem, but our issues are happening in both Wifi and Wired. 

2017-4-9, 18:50:16

Critical (3)

Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=b0:7f:b9:xx:xx:xx;CMTS-MAC=00:01:5c:7f:9a:5a;CM-QOS=1.1;CM-VER=3.0;

Our MAC address is the first one listed in the event log.  CMTS-MAC=00:01:5c:7f:9a:5a I believe is a Comcast Server somewhere. 

The nic was made by MAC-Addr 00-01-5C-7F-9A-05            CADANT INC., USA
4343 Commerce Court - Ste. #207 - Lisle IL 60532.

In our case I think that the issue has to do with stability of Comcast because of our last test which showed packet loss.  I can get about 5 seconds of the beginning of calls, then nothing for about 20 seconds, then the call is ok.  It is intermittent.  If something would just break, we would know where the issue lies. 

[dlf_texas]

I don't know what happened but my internet has be pretty stable for months.

I have not had to reboot at all.

I took out the 3db attenuator that I had installed and then at some point things just got better on their own.

I have noticed that TWC is now bonding to ALL 24 channels on the modem for downstream.

That may have something to do with it.

Before it was only bonding on 16 channels.

It would be interesting to know how many channels are bonding on those with drop issues.

[8th_Day]

The maual is not very good in interpreting the chart and not sure that I am interpreting the screen correctly, but I think that there are 24 Downstream Channels and only 4 Upstream Bonded Channels.

Downstream Bonded Channels

Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables 1 Locked QAM256 17 615000000 Hz 6 dBmV 40.1 dB 0 0 2 Locked QAM256 1 519000000 Hz 6.7 dBmV 40.7 dB 0 0 3 Locked QAM256 2 525000000 Hz 6.3 dBmV 40.5 dB 0 0 4 Locked QAM256 3 531000000 Hz 6.2 dBmV 40.5 dB 0 0 5 Locked QAM256 4 537000000 Hz 6.1 dBmV 40.5 dB 0 0 6 Locked QAM256 5 543000000 Hz 6.2 dBmV 40.6 dB 0 0 7 Locked QAM256 6 549000000 Hz 6.2 dBmV 40.5 dB 0 0 8 Locked QAM256 7 555000000 Hz 6.2 dBmV 40.5 dB 0 0 9 Locked QAM256 8 561000000 Hz 6.1 dBmV 40.4 dB 0 0 10 Locked QAM256 9 567000000 Hz 6 dBmV 40.4 dB 0 0 11 Locked QAM256 10 573000000 Hz 5.8 dBmV 40 dB 0 0 12 Locked QAM256 11 579000000 Hz 5.9 dBmV 40.2 dB 0 0 13 Locked QAM256 12 585000000 Hz 5.9 dBmV 40.4 dB 0 0 14 Locked QAM256 13 591000000 Hz 5.9 dBmV 40.3 dB 0 0 15 Locked QAM256 14 597000000 Hz 5.8 dBmV 40.3 dB 0 0 16 Locked QAM256 15 603000000 Hz 6 dBmV 40.3 dB 0 0 17 Locked QAM256 16 609000000 Hz 6.7 dBmV 41.4 dB 0 0 18 Locked QAM256 18 621000000 Hz 6.6 dBmV 41.3 dB 0 0 19 Locked QAM256 19 627000000 Hz 6.4 dBmV 41.4 dB 0 0 20 Locked QAM256 20 633000000 Hz 6.6 dBmV 41.4 dB 0 0 21 Locked QAM256 21 639000000 Hz 6.6 dBmV 41.4 dB 0 0 22 Locked QAM256 22 645000000 Hz 6.6 dBmV 41.4 dB 0 0 23 Locked QAM256 23 651000000 Hz 6.5 dBmV 41.4 dB 0 0 24 Locked QAM256 24 657000000 Hz 6.6 dBmV 41.4 dB 0 0

Upstream Bonded Channels

Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power 1 Locked ATDMA 81 5120 Ksym/sec 36400000 Hz 43.5 dBmV 2 Locked ATDMA 82 5120 Ksym/sec 29500000 Hz 43.3 dBmV 3 Locked ATDMA 83 5120 Ksym/sec 22600000 Hz 42 dBmV 4 Locked ATDMA 84 5120 Ksym/sec 15700000 Hz 42.5 dBmV 5 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 6 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 7 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV 8 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV

[NCsandhills]

TWC-Spectrum service upgraded to 24 down / 4 up recently. Here is a good site to check your connection's performance: https://www.dslreports.com/speedtest.

From "SpeedGuide.Net" web site:

Downstream Power (-15dbmV to +15dbmV) - measure of the signal level received by the cable modem
Most modems are rated from -15dB to +15dB, however it's best to have it between +8dB and -8dB. Anything less or more than that and you may have quality issues. You can remove splitters on the line if you need to raise and clean up your signal level a bit. You can also use a tap (directional coupler) to get a cleaner signal to the cable modem instead of a splitter.

Upstream Power / Modulation(37dbmV to 55dbmV) - the strength of signal transmitted by the cable modem
Generally a lower this number is better. Above 55dB will most likely cause problems, over 57dB and you probably won't be able to connect. Ideally between 42 and 50dB. Lower than 40 may start introducing some packet loss (especially if you have much noise on the line). If you hit 58 the modem will likely drop the connection and resync.

Signal/Noise Ratio (SNR , >30dB) - measure of how clear the signal is
SNR is best over 30, (the higher the better, might work well with as low as 25 at times). Anything less than 25 will cause dropped connections, packet loss, slow transfers, etc. This is true for both the "Downstream SNR" and the "Upstream SNR", which may be different values. Typically, cable modems show the Downstream SNR, the Upsteram SNR can only be calculated at the remote end of the coax (usually at the node). Just remember that higher SNR means cleaner signal. A value well over 40 may mean you have too much power.

[JimPugilist]

C7000-100NAS 

seems to be fine.....

69.2

megabit/s

12.65

megabit/s

GA, USA	32ms
DC, USA	44ms
NY, USA	48ms
DE, USA	53ms
IL, USA	55ms

Created with Highcharts 4.2.7+2ms+2ms+2msBufferbloat

Overall

B

BufferBloat

C

Quality

A

Speed

-

Results + Share

[junfitz]

Seems like this problem hasn't been resolved. Yesterday, I called Netgear support and the person I spoke with, was confident that he could fix this problem.  He said, some configurations in the settings need to be done and he's already done it for multiple people and fixed their problem.  But the Catch is, i have to pay $49.99 for him to be able to tell me the correct configurations since I'm more than 90 days past the purchase date.   Also, their 1 year warranty only covers Hardware Issues.  I don't know about you but to me, if the product does not work, I consider it a hardware issue and should be taken care of by the company.  We consumers deserve better support than your company policy offers.  

Maybe Corporate needs to hear from FTC.gov first before they change their policy for resolving consumer's problems.  It's ridiculous how Netgear policy would not allow their Tech Support to configure a $200 modem/router past 90 days from purchase date without having to pay an extra $49.99.

These random drops almost cost me my job.   I was working from home one day, and i was working on moving a doctor's file from a VPN drive to another. Half way through the transfer, I lost internet connection for 5 minutes.   Guess what happened to that file?  Corrupted. Incomplete. Error.   I'm glad I had a backup copy of that file because if I didn't, I would've lost my job and lawsuits against Netgear will be filed.

[NCsandhills]

From "www.techrepublic.com":

Users successfully establish a VPN connection, but the connection periodically drops

There are a number of places you can check to try to nail down this problem. First, verify that your computer did not go into standby mode, hibernate, and that a screen saver did not pop up. Standby and hibernation can interrupt your network connection when the VPN client expects a constant link to a VPN server. You may also have configured your machine to shut down a network adapter after a certain amount of time in order to save power.

If wireless is in use, you may have wandered to a location with a low (or no) wireless signal (not the case here), and the VPN might have dropped as a result. Further, you might have a bad network cable, problem with their router or Internet connection, or any number of other physical connection problems.

Other Comments: Can you determine if the "disconnect" was from the PC to the wireless router, or was it from the internet source (cable) to the Modem? This would confirm whether the disconnect is an ISP problem or a Cable Modem/Router problem. The Unit's internal software (version number, etc.), can only be changed by the Manufacturer or the ISP provider.  However, I suspect the the Customer Service person can only change the settings that are available to the end-user. You might have a setting that is not the best for a VPN connection - and this setting can be either on the Cable Modem/Router or the PC's WiFi Adpater.  You may need to review these settings and "experiment".  Again, before "experimenting", see if you can confirm where the disconnect occurs - at the modem or between the Router and PC. If you have a HardDrive connected to the Router and can access the HD but not the internet - then the problem is with the ISP and/or the Cable connection. 

[bronzelincolns]

i will no longer be dealing with the company and it's products. i've been out of a intenet connection for the last 3 days. in these 3 days i've had access to the web for 10 minutes only for it to go out again.

i've already sent for another modem/router from another company and will be taking this one back as i'm well within the return window.

i won't mention the abysmal CS.

lesson learned. don't deal with netgear.

[scsinykin]

I am not a computer engineer, but my son is.  My ISP is small and says they don't have the ability to upgrade firmware.  Netgear promised to send me a replacement with upgraded firmware (to .23 release, from .15) but what they sent me STILL has the old firmware, still  has problems with intermittent wifi dropping of signals.  I have spent HOURS today, trying to trouble shoot--hours on the phone with Netgear who now says their "new" modem-router does not come with suport!  Netgear wanted me to pay $49, after they'd kept me on hold.  They promised again to send a new modem-router, this time with the updated firmware, but the promised email, detailing their agreement never came.  I am at my wit's end.  If I'm to throw out this $200 piece of equipment, what IS a reliable modem AND router, or modem router?  I just don't have the expertise and patience to keep dealing with this kind on NON-customer support!

[NCsandhills]

At this time (for you), there may be only one fix for this problem (other than a different brand of equipment) - the C7000 needs to be "reset" in order to return to proper functionality.  This can be easily done each night (or early morning) by using a $5 electrical timer that disconnects power to the C7000 each day from 10 minutes to an hour - what ever is most convenient for setting the timer's "ON" operation.  Shutting OFF and then powering up the unit with restore it's functionality until the Cable Supplier's signal again causes the C7000 to malfunction.  If the malfunction occurs when your needing internet service, then logon to the C7000 and reset the Modem from your PC.  On "restart", the problem should be resolved.  The updated C7000 software requires the Cable company to install, since the revised software must be compatible for their system.  The problem you are experiencing will be resolved once the Cable company upgrades their service.  This is a good example/reason for using separate modem and router units.  In the case of the C7000 modem/router, it is likely that the modem section is at fault - or the combination of this particular modem and the Cable company's system.

[BigDog2017]

Thank you for the reply.  Actually tried the reset and several other approaches. Seems kind of senseless to have to do a power interupt in order to get a device working correctly IMO. This particular C7000 was the problem.  Since repalcing this device on my network over a year ago, service has been flawless.

[dlf_texas]

I can also attest that using a electirical timer to power off the router once per day works.

This is considered a COLD REBOOT because you are removing power from the unit.

It is finally what I had to do and things seem to be fine most of the time.

There are still occasions when I need to do a manual REBOOT.

For a manual REBOOT you want to login to the router and do a "REBOOT" not a reset.

This is considered a WARM REBOOT because power is never actually removed from the unit.

A reset would reset the modem to factory defaults which may not be what you want.

My router has the .23 firmware but I have not removed the timer yet. This will be something I will try one day.

[BigDog2017]

In my opinion having to do a frequent reset (of any kind) is not a viable solution and is most certainly a horrible user experience.  

[scsinykin]

Thank you for the feedback.  I've just looked around the Netgear Gateway and cannot find the place where one is able to REBOOT from the computer.  I have been unplugging.  My ISP says perhaps the level of my internet service (50 mg) is responsible for the dropped connections.  I don't know enough about any of this to know whether that is accurate.  He is recommending 100K and thinks that will resolve the issue.  Does anyone have knowledge whether this is true?

[dlf_texas]

[bfinley1959]

I have been having this same issue and finally had it with the Netgear C7000!  I went and bought an Arris SPG6950AC2 and the problem is gone!  I wounder what action you have to take to get these devices replaced as I am sure NetGear is very aware of the "loss of sync" issue as it has been reported many times in this forum.  I was a loyal customer until this purchase and constant fight to get it to work reliably.has changed my opinion on NetGear.  Out of warranty and off the hook is my take on this..

[mlawaljr1]

So I've read most of the post on here because I was having the come problem as most of you. (Dropped service). I tried just about everything from changing dns settings to coming coaxial cables to troubleshooting with tech support to no avail. Finally I decided to go to my local Comcast and get a Comcast modem. Talked to the customer service representative for about 10mins and I discovered a few things with my specific problem. So he advised me to try and running the line from the pole directly to my modem (c7000). As I did what he suggested.......it worked!!! But that's not where my modem normally resides. So I went to Best buy and bought 25ft worth of coaxial cable and got to work. To make this story shorter..... My internet is back up and running again with normal speeds. What I think happened: when my internet was installed they used 2 splitters on the internet line. I moved the modem upstairs and I needed more line but didn't have long enough line. So I used more splitters without realizing they already had a few on that specific line. At first I didn't have any dropped signals then a month later everything went crazy. So I took all the splitters off and ran a direct line from pole to the modem. I reset my modem and then had Comcast resend a signal and now I don't have any more problems whatsoever. Like I said this is my personal experience but hopefully someone will benefit from my experience.