Orbi WiFi 7 RBE973
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C6300 Frequent disconnects

Sloy
Tutor

C6300 Frequent disconnects

Seems to be a common topic here, but don't think I've seen a definitive answer so gonna try again.

 

Purchased a C6300 because it was (seemingly) the best modem / router out there supported by Comcast.  Not cheap, IMO, so kinda had high hopes, but...not so much.

 

Some background....

 

Prior to puchasing this I had a comcast box that just wasn't cutting it.  The range / power of the device that I was "renting" from Comcast couldn't reach many parts of the house so wanted a solution.  First thing I did was to purchase a Lynksys LAPN600 Access Point, which did the trick wonderfully.  However, I was still renting they modem / router from Comcast, so to be rid of them once and for all purchased the C6300.

 

The pros - the signal is strong.  Like the interface as well and set up seemed easy enough.  But the Cons - ugh - Frequent Disconnects.  A better discription would actually be "micro" disconnects because they last about 15 seconds.  They are so fast that the wireless devices (iOS devices and 3 Windows 7 laptops) don't even show they are disconnect.  In fact, hovering over the network icon shows it's connected, but if I'm surfing the net during a micro-disconnect it will say page cannot be displayed.  Again, it's all Wireless devices at the same time, so I know it's not a laptop / iPad / iPhone issue.

 

Thinking that perhaps it's the Linksys AP that might be the issue - as in, maybe the AP is too close to the C6300 and somehow they are competing for connection.  Hope.  Disabled the Linksys completely - both by powering it off physically and by turning the Radio on the AP off.  Still, disconnects.

 

I've tried to read the logs on the C6300, but the only logs I can find are really of no help.  There's something about repeated DoS attacks, but the timings dont really correspond to when the micro-disonnects happen.  Methinks events such as this SHOULD be captured somewhere, but...where?

 

I was actually frustrated enough that I called Netgear support since the device is sitll new.  And then I got REALLY frustrated.  The tech I spoke with told me to reboot the device since it had done a recent Firmware update.  I explained that I was current with Comcast - v1.02.21 - but he was rather insistent.  So I reset, per his request.  It had been up just a few minutes after the reboot and he asked if I saw the disconnect issue. "No", says I, "but it's very random and I don't know what a reset would do anyway!"  I inquired if there were logs to look at, to which he had a snarky response to the effect of "If I thought there was something to learn from the logs I would have done that already."  Well, Mr. Smarty pants was a huge fail, because even though I had no drops in the five minutes we spent after the reset, it started the mico-disconnects but a few minutes after I hung up with them.  Brother....

 

So, I've tried everything I can think to do and yet get the haunting suspicion that I'm missing something - probably something very...basic.  In summary...

 

- I don't believe it to be my wireless devices because when it happens to one device, it happens to all of them.

- I don't believe it to be the AP that I have since the issues persists with the AP offline / disabled

- I've also disabled the Wireless 2.4 and 5 on the C6300 and used the signal from the AP, and the frequent micro-disconnects still happen.

- I suppose it COULD be a Comcast issue, but given that I've one all "rogue" on them and am no longer renting my modem / router from them, they probably won't give me the time of day if I open a case with them.

 

Would love to figure this out. I want to make this device work because I've heard others say very good things about it and stats & feature wise it looks to be better than anything else out there that comcast supports.

 

Any suggestions?  Am I missing some logs that might give me an indication of what is happening, either on the 6300 or in Windows maybe?

 

Thanks for ANY help...

 

- S

Message 1 of 65
ElaineM
NETGEAR Employee Retired

Re: C6300 Frequent disconnects

Hi @Sloy,

 

Welcome to the community!

 

We apologize for the frequent disconnect that you are having. When the disconnection happens, what LED lights are on from the C6300? How frequent is the disconnection in a day (every day, hour, 30mins. etc.)? You may want to try adjusting the MTU size on your unit. Check this link to get the proper MTU size on your unit. MTU can be adjusted by access the GUI of your C6300 under Advanced > WAN setup. By the way, what is the firmware loaded on your unit? Can you verify if you have the latest fw version from this page. Let us know the result.

 

Regards,

Message 2 of 65
Sloy
Tutor

Re: C6300 Frequent disconnects

Holy cow, ElaineM - was out of town and didn't see your reponse a few days ago.  Thank you SO much for trying to assist!

 

So, to answer your questions...

1. Not sure about LED lights since I don't sit within view of the Device.

2. The Micro-disconnects happen about every 10 - 15 minutes, but sometimes only once an hour, and sometimes once every five minutes.  As I test, I opened cmd and did the following - ping -t 192.168.0.1  I ran this from my desktop hardwired to the device AND my laptop.  When the micro-disconnects happen, on the Desktop there is no change - just repeated pings to the device.  HOWEVER, on the desktop there are 4 ping attempts each time that are unsuccessful - "Request Timed Out" exactly 4 times each micro-disconnect.  Always 4, so even though each disconnect is NOT on a fixed inverval, each is exactly the same amount of time.

 

Also, noticed something interesting that hadn't noticed before.  Even though I answered the prompt to automatically log into my SSID, it never does anymore.  I can see it, and select it, but it never auto connects to it.  Curious.

 

Anyway, when home I will for sure check out the MTU size - very interesting.

 

Lastly, my firmware is v1.02.21, which, according to Comcast, IS the latest, greatest?

 

Thanks again for your help...

 

-S

Message 3 of 65
Sloy
Tutor

Re: C6300 Frequent disconnects

OK, did the MTU test and that's definitely not the issue.  Did the test you suggested and @1472, things were fine, at 1473, got packets need to be defragmented.  So, 1472 it is, plus 28 that equals 1500.  WHICH, as it turns out, is EXACTLY what was already in WAN Setup.

 

Given that nothing happens to the computer that is hard-wired to the C6300 and the micro-disconnects only affect devices connected WiFi - regardless if it's to the AP or to the Router, am I missing some WiFi setting?

 

Any OTHER suggestions?

 

-S

 

Message 4 of 65
ElaineM
NETGEAR Employee Retired

Re: C6300 Frequent disconnects

@Sloy On the Advanced Wireless Settings, change your Fragmentation Length and CTS/RTS threshold to 2304. Observe what happens.

 

Regards,

Message 5 of 65
Sloy
Tutor

Re: C6300 Frequent disconnects

OK, have made the change and will see if there's a difference.  Leave Preamble mode to Long Peamble?

 

FWIW - the values were

 

Fragmentation Length: 2346 (Which looks like it was the MAX)

CTS/RTS Threshold: 2347 (Which looks like it was the MAX)

 

 

Message 6 of 65
Sloy
Tutor

Re: C6300 Frequent disconnects

Just realized why this probably WON'T work - on that same page I've actually unchecked the Wireless Gateway Radio because I'm pushing my WiFi through my Linksys Access Point.  However, as I mentioned previously, whether I use the AP and disable the C6300 or if I use the C6300 and disable the AP to broadcast my WiFi, the micro-disconnects still happen.  And to be sure, when I say I've disabled the AP, I've tried turning off the broadcast AND pulled the power from it - either way, the C6300 alone experiences the same disonnects.

 

Also, why I don't think the Linksys factors into things is because prior to getting my C6300, I used a Comcast Gateway and had NO disconnects.  The Comcast device was way under powered, but using the Comcast and Linksys did NOT cause the same issues.  As such, the only "new" factor is the C6300.

 

-S

Message 7 of 65
Sloy
Tutor

Re: C6300 Frequent disconnects

Some good and bad news to report.

 

Made the changes per your suggestion AND flip flopped so that my C6300 was pushing WiFi and NOT my Linksys AP.  At first, the transition was rought.  Used ping -t 192.168.0.1 to see how things were going and sure enough, after a few minutes I was disconnected.  Only, unlike my brief micro-disconnects, I was down for a few minutes.  As before, during the entire issue, my computer showed that it was still connected and it looked normal, but I was unable to connect to any website and my pings were all failing.  WiFi was indeed down again.

 

However, once connected...I actually made it through the entire night without ANY further disconnects - significant ones OR micro-disconnects.  This was the first time I've made it through the whole evening and morning without any interruptions, which is VERY positive.  I'll let this go for a few days and report back - maybe, just maybe, the changes made have resolved this.

 

So hopefull....

 

-S

Message 8 of 65
ThoughtA
Aspirant

Re: C6300 Frequent disconnects

Does it seemed to have been resolved still? I have a similar problem but with ethernet too, and I'm writing up my own post now. I'm curious if you found this helpful, though.

Message 9 of 65
Sergii_Puliaiev
Aspirant

Re: C6300 Frequent disconnects

Hi,

 

i am experiencing the same issue..

Have just upgrded my modem from C3700 to C6300 - and got disconnected from WorldOfWarcraft every 5-10 minutes...

 

Any web page - looks good  - so the disconnection itself is short of time.

 

Any updates on this?

Provider : Wave Broadband

Hardware Version V3.0

Firmware Version V1.02.21

 

Previous modem : Netgear C3700 - no issues like this.

Message 10 of 65
ThoughtA
Aspirant

Re: C6300 Frequent disconnects

I've found that connecting to a VPN alleviates the issue. I've been using Private Internet Access and their client. I think it has something to do with error-checking and the client not sending bad packets. While this is a solution, it's still really crappy to have to deal with the drawbacks of a VPN just to have a stable connection.

Message 11 of 65
Cloud0359
Aspirant

Re: C6300 Frequent disconnects

Hello,

 

Does anyone have any real solution to the disconnect problem?  I've been having this issue and was nearly floored when I found out it was the modem I just purchased.  This is crazy.  Is there anyone available to walk me throught correcting this problem?

 

I will greatly appreciate any help.

 

Message 12 of 65
ThoughtA
Aspirant

Re: C6300 Frequent disconnects

From everything I can tell, no. It's happened for multiple c6300s for me now. Netgear customer service has been great, but I think this is a systemic issue. I suspect something with my PC or ISP or my building does not play well with the modem, and another c6300 likely won't fix the problem.

 

Like I said above, running a VPN on my desktop seems to alleviate the issue 99-100%. However, there's no need to do so on our laptop or phones. This makes me think the most likely suspect is something on my PC that's not playing nice, though I'm very far from certain with that.

 

To be honest, if it's still even somewhat convenient for you to change to a different modem/router, that would probably be best. I often go through long periods of time without the disconnections, but the times I have the disconnections can be very frustrating.

 

Edit: I forgot to mention that someone has a suggestion that worked for him here. I completely forgot about it, so I haven't tried it yet. Of course, it'd be nice to not have to force half duplex.

Message 13 of 65
sajjadazamkhan
Aspirant

Re: C6300 Frequent disconnects

Having the same exact issue as described by other users, I bought a new modem and its frustrating me so much that i am connected via ethernet and completely shutdown the wifi. It has been pissing me off that i feel like throwing this in the garbage. I opened a TAC case with Netgear and that has been just a waste of time. I am down with 250$ and have a device that does not work.

Model: C6300|AC1750 Cable Modem Router Docsis 3.0
Message 14 of 65
DarrenM
Sr. NETGEAR Moderator

Re: C6300 Frequent disconnects

Hello sajjadazamkhan

 

In the event logs of the modem are you getting any type of errors or timeouts if so what is it saying?

 

DarrenM

Message 15 of 65
doc101
Aspirant

Re: C6300 Frequent disconnects

I think I have finally solved this on my Win 10 desktop. After looking through the Windows system event log I saw that the disconnects were an hourly issue. This led my to discover that it was a DHCP issue. Something about my Win 10 desktop doesn't play well with the C6300 DHCP. My Win 10 laptop generally is fine, although I've seen it do the same thing once or twice.

 

So I ended up reserving a small address range for static address in the modem settings. I then configured my adapter properties to a static IP address and also manually configured my DNS servers which I had previously looked up via ipconfig /all when I was still using DHCP.

Model: C6300BD-1TLAUS|DOCSIS 3.0 Cable Gateway Wi-Fi AC
Message 16 of 65
PFunk
Aspirant

Re: C6300 Frequent disconnects

I too am having the same issue.  It will drop my Wifi signals completely.  I verified using the Wireless Channel page that I am not seeing conflicts.  Doesn't mean there aren't any, but I've changed to many different empty channels with same result.

 

I've also moved since I got this modem and it happens at both my old and new residence.

 

Wifi signals drop off after a couple hours and require a reboot/unplug to get them going again. I'm extremely disappointed with this purchase.  

 

I've tried disable one or the other wifi radio and still run into the issue.

I've changed the MTU to the recommended setting as described in a previous post, no help.

I'm running the latest firmware.

I changed CTS/RTS Threshold to 2304 as recommended in previous post.

 

Any additional thoughts?

Model: C6300|AC1750 Cable Modem Router Docsis 3.0
Message 17 of 65
DarrenM
Sr. NETGEAR Moderator

Re: C6300 Frequent disconnects

Hello Pfunk 
 

You may want to contact Netgear support at this point if the router is still under warranty if its only just the wifi dropping. Have you tested the Ethernet when you get the drop outs to see if its still working?

 

DarrenM

Message 18 of 65
alex71
Initiate

Re: C6300 Frequent disconnects

BUYER BEWARE. After two months of random disconnects and several modem replacements I am 100% sure this is a NETGEAR hardware issue. It's a faulty design and cannot be fixed.  First of all I build computers and I have a lap top, desktop, tablet, and cell phone all connected to test with. Every device has intermittent drops often every 15 minutes. NETGEAR is more than willing to send mail me modem replacements but that never fixes the issue. Comcast came out five times a supervisor determined the modem was the problem.  Comcast then loaned me a test modem so I could have both connected at the same time. With NETGEAR I had disconnects every 15 minutes.  With the Comcast modem I left my computer running for a week connected to an online game and it never disconnected once.  Frankly I would warn people not to buy this product as the defect is in the design and NETGEAR made it clear "REFUND IS NOT AN OPTION."

Message 19 of 65
Thehawk
Guide

Re: C6300 Frequent disconnects

Same problem. It seems like to navigate these solutions you must be a computer expert. I think it's awful customer service that you can call the support line for free for 90 days but for the rest of your warranty period you have to pay.
Message 20 of 65
DarrenM
Sr. NETGEAR Moderator

Re: C6300 Frequent disconnects

Hello Thehawk

 

Can you describe the issues that you are having is it the wifi dropping or the modem dropping Internet?

 

DarrenM

Message 21 of 65
cybrmstr
Tutor

Re: C6300 Frequent disconnects

Well from searching around these disconnects are a design issue and in sure netgear isnt going to do anything about.  Darren the administrator seems like hes trying to help but based on the number of people that have submitted the EXACT same issue there isnt a solution and Im guessing that darren is allowed to tell you that.

 

I guess its time to get something from Cisco.

Model: C6300|AC1750 Cable Modem Router Docsis 3.0
Message 22 of 65
Thehawk
Guide

Re: C6300 Frequent disconnects

Yes I'm sure it's a net gear issue and I'm hugely disappointed with them. Their phone service dept want to charge me $150 to fix the iproblem which they tell me is an issue with broken network protocols.
Comcast says there's no problem on their end - my modem is still under warranty but netgear has been no help in fixing the problem.
I have changed the frequency that the modem transmits at. That didn't fix the problem.
Message 23 of 65
sealskin
Aspirant

Re: C6300 Frequent disconnects

I am yet another C6300 owner with frequent internet disconnects.  I posed my issue in a new thread before finding this one. I was amazed to log into this forum and see so many of us. I am seriously regretting my purchase right now and floored that netgear hasn't addressed it properly.

Model: C6300BD-1CXNAS|Docsis 3.0 AC1750 Cable Modem Router
Message 24 of 65
Thehawk
Guide

Re: C6300 Frequent disconnects

I'm still having the same problems. I changed the frequency on the router and it still disconnects
Right now I'm using my phones wifi service as a hotspot because the netgear C6300 has disconnected itself again
Message 25 of 65
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