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Consistent Comcast DNS Issues

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Consistent Comcast DNS Issues

To start off with I'm an career IT Systems Engineer, so bare in mind that asking things like "make sure it's plugged in" and "try restarting your computer" are not necessary......

 

I switched from Comcast Business for home office internet to Comcast Residential about 8 months ago when I moved and had the opportunity to get Xfinity Gigabit. I went the whole nine yards, I got the XFi XB6 gateway, I got the Xfi Pods. When I first setup everything, I was super happy and never looked back.

 

Fast forward to about November and all the sudden I've noticed consistent drops in my internet connection. The gateway is accessible and even the diagnostics on the gateway reflect that "everything is working fine" but it's not and I cannot figure out a resolution. When the network suddenly stops responding I am not able to resolve any dns lookups. So pinging google.com returns host not found but pinging 8.8.8.8 responds instantly. If I use the gateway diagnostics to ping www.comcast.net though it will work about 70% of the time, usually though the issue resolves itself about the time I get to the gateway to investigate.

 

This happens at all times of the day, I've seen it in the mornings, afternoons, evenings and middle of the night. Usually it resolves itself in a matter of minutes but soemtimes I have to reset the wifi and router modules using diagnostics, once in a while I have to restart the gateway using diagnostics, once in a blue moon I have to power cycle the gateway.

 

I'm wondering if this is a documented issue or if there's something I can do about it? I noticed with XFi that I cannot change the DNS, I'm 95% sure that's because a lot of the parental controls and filtering facilitate the functionality using DNS. While yes, I could set static DNS on devices other than my kids, that's not ideal of course. I spent a lot of money on getting all this setup and getting the equipment. I really don't think it was ethical for Comcast to make me buy proprietary wifi mesh pods when I cannot buy a gateway but that's another subject....

 

Looking for thoughts or suggestions before making a call to customer service or making a formal complaint. 

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Silver Problem Solver

Re: Consistent Comcast DNS Issues


@dailen wrote:

To start off with I'm an career IT Systems Engineer, so bare in mind that asking things like "make sure it's plugged in" and "try restarting your computer" are not necessary......

 

I switched from Comcast Business for home office internet to Comcast Residential about 8 months ago when I moved and had the opportunity to get Xfinity Gigabit. I went the whole nine yards, I got the XFi XB6 gateway, I got the Xfi Pods. When I first setup everything, I was super happy and never looked back.

 

Fast forward to about November and all the sudden I've noticed consistent drops in my internet connection. The gateway is accessible and even the diagnostics on the gateway reflect that "everything is working fine" but it's not and I cannot figure out a resolution. When the network suddenly stops responding I am not able to resolve any dns lookups. So pinging google.com returns host not found but pinging 8.8.8.8 responds instantly. If I use the gateway diagnostics to ping www.comcast.net though it will work about 70% of the time, usually though the issue resolves itself about the time I get to the gateway to investigate.

 

This happens at all times of the day, I've seen it in the mornings, afternoons, evenings and middle of the night. Usually it resolves itself in a matter of minutes but soemtimes I have to reset the wifi and router modules using diagnostics, once in a while I have to restart the gateway using diagnostics, once in a blue moon I have to power cycle the gateway.

 

I'm wondering if this is a documented issue or if there's something I can do about it? I noticed with XFi that I cannot change the DNS, I'm 95% sure that's because a lot of the parental controls and filtering facilitate the functionality using DNS. While yes, I could set static DNS on devices other than my kids, that's not ideal of course. I spent a lot of money on getting all this setup and getting the equipment. I really don't think it was ethical for Comcast to make me buy proprietary wifi mesh pods when I cannot buy a gateway but that's another subject....

 

Looking for thoughts or suggestions before making a call to customer service or making a formal complaint. 


Are the drops with wifi devices only?  I passed on the Pods because they are not true mesh devices.  I went the expensive route and got the Orbi and I am using the XB6 as my modem and the Orbi for ethernet and wifi.  It's much more reliable.


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I am just a customer, volunteering my time to help other customers here in the Forums.
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Frequent Visitor

Re: Consistent Comcast DNS Issues

Hi, I am experiencing the exact issues, intermittent DNS outages are the symptom I am experiencing.  Likewise, I've been in data/telecom for 30 years, so I don't think it's a simple pc or home router issue. This is quite frustrating during the day. Sometimes it self resolves in 5-10 minutes and if not I have to hard reboot the GW. I am using all IPV4 and IP pings to 8.8.8.8 are always good. My router (ASUS) also reports the WAN cable as disconnected, but the pings to the WAN IP still work.

Have you been able to resolve this issue? Any tips would be appreciated! 

-Thanks

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Frequent Visitor

Re: Consistent Comcast DNS Issues

UPDATE

It just happened again.

I went into the GW GUI.

I Navigated to Troubleshooting, Reset/Restore Gateway, RESET Wi-Fi ROUTER. 

This resolved the current DNS issue and it only took 90 seconds.

It does point more to the GW than any other components on the net.

It's not a FIX, but at least I can get back in the net faster. 

 

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Frequent Visitor

Re: Consistent Comcast DNS Issues

Following.  My parents are having intermittent issues.  Windows Remote assistance won't connect, and other screensharing websites won't load when they have this problem so I can't do much troubleshooting.  At least mail server hostnames resolve, or are cached, as mail does work.   Hopefully someone in this thread will have a great solution.  I'd really like to be able to change their DNS to resolve against OpenDNS.  They've got the Comcast combo modem/router. 

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Gold Problem Solver

Re: Consistent Comcast DNS Issues

If you're seeing drops and unresolved DNS issue on your Comcast modem, there might be some signal issues at the premise. Let's investigate. 

 

All if you are seeing these issues, please send me a private message with your full name for help. 

 

Ken


I am a Retired Official Comcast Employee and no longer actively support the Xfinity Forum.
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Re: Consistent Comcast DNS Issues

Thanks Ken.  My parents contacted support, and a tech actually replaced the modem.  The tech said it had a good signal.  I'm going to check it out to make sure it isn't a problem with their computer, and then will re-engage you/support if necessary.  I was just looking for recent threads on DNS, since that seems to be the root of their problem.  I was finally able to talk her through changing DNS to 8.8.8.8 as a test, but unfortunately, that didn't fix the issue.

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Gold Problem Solver

Re: Consistent Comcast DNS Issues

b_777, appreciate the update. Was there no change after the modem swap? Looking forward to your update. 


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Re: Consistent Comcast DNS Issues

Sorry, you indented to communicate a different user and got me instead...

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Re: Consistent Comcast DNS Issues

I have the same issue with "resolving host..." on Xfinity Blast internet with new Arris SB8200 and TP-Link Archer A9 wi-fi router.   I suspected cable wiring issue and Xfinity sent out a tech to review connections.  Problem still there.  Suspected SB8200 cable modem and swapped that out.  Problem still there.  Replaced TP-Link router and problem still there.  Very intermittent and appears whenever our laptops have been inactive for 10 or 15 minutes.  Constant 'reload' of browser eventually resolves the host name.  Streaming video over Roku for hours is never a problem.  Always rock solid video.  Laptops are HP Win10 and Dell Win10.

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Gold Problem Solver

Re: Consistent Comcast DNS Issues

I have the same issue with "resolving host..." on Xfinity Blast internet with new Arris SB8200 and TP-Link Archer A9 wi-fi router.   I suspected cable wiring issue and Xfinity sent out a tech to review connections.  Problem still there.  Suspected SB8200 cable modem and swapped that out.  Problem still there.  Replaced TP-Link router and problem still there.  Very intermittent and appears whenever our laptops have been inactive for 10 or 15 minutes.  Constant 'reload' of browser eventually resolves the host name.  Streaming video over Roku for hours is never a problem.  Always rock solid video.  Laptops are HP Win10 and Dell Win10.

glmonson, thanks for posting! Are you only having the issue on the Laptops? I know you said you're seeing drops on the Roku but are you seeing any issues on your cell phone for example? 

 

Ken


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Re: Consistent Comcast DNS Issues

Resolving host (DNS) issue is on LAPTOPS.  Both Dell and HP.

The ROKU streaming video is always good with no issues.

"Streaming video over Roku for hours is never a problem.  Always rock solid video."

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New Poster

Re: Consistent Comcast DNS Issues

I'm glad I found this post because I also have the same issues.  I've been a sys admin for 15+ years and it smells like a DNS issue. It's not the Chrome glitch either. I have a netgear CM1000 and thought perhaps that was the problem child. Come to find out users with an Arris SB8200 are having the same problems. I've done all the standard stuff, flushdns, reset, winsock reset, rebooting the modem etc. It's random when this occurs but very frustrating. Yes I coud try setting DNS static but how many of your customers would know how to do this. They are paying a pretty high price for your service. I have Performance Plus with Gigabit Internet , Win 10 1903, Cable modem Netgear CM1000, Router Asus ASUS RT-AC1900P.

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Re: Consistent Comcast DNS Issues


@bino2 wrote:

I'm glad I found this post because I also have the same issues.  I've been a sys admin for 15+ years and it smells like a DNS issue. It's not the Chrome glitch either. I have a netgear CM1000 and thought perhaps that was the problem child. Come to find out users with an Arris SB8200 are having the same problems. I've done all the standard stuff, flushdns, reset, winsock reset, rebooting the modem etc. It's random when this occurs but very frustrating. Yes I coud try setting DNS static but how many of your customers would know how to do this. They are paying a pretty high price for your service. I have Performance Plus with Gigabit Internet , Win 10 1903, Cable modem Netgear CM1000, Router Asus ASUS RT-AC1900P.


It sounds like it may be an issue with specifice hardware; I have had Xfinity Gateways for several years and never had a DNS issue.  My present gateway is the Artris TG3482G.


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Re: Consistent Comcast DNS Issues

@bino2 

I also have a RT-AC1900P (Firmware Version:3.0.0.4.384_45717and it is hardwired (5' Eth Cat 6) to my Comcast GW. The ASUS is the front end to my entire LAN. Rebooting it does not solve the problem, but rebooting the Comcast Cable Modem does.

Also, what I think is the same issue is with my Samsung TV hardwired to the Comcast GW. 

Maybe the ASUS is screwing up the GW?

Are you seeing similar? 

john

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Re: Consistent Comcast DNS Issues

Streaming Roku is rock solid.  If either laptop is inactive for 10 or 15 minutes the wifi link stays up but no internet connection.   Then, no DNS resolution until we try 8 or 9 reloads and then it links up to the internet.  Switched cable modems, switched wifi router and replaced CAt6 cable between modem and router.  Really think the issue is with Comcast Blast service.

Using Chrome and Firefox both lastest.  Win 10 on both.  Mcafee firewall on one and Windows Defender on the other.  Both behave the same/

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Re: Consistent Comcast DNS Issues

I have noticed my Netflix and Amazon streaming moves work great if they start when there are no issues with other devices. Once the DNS complete the lookup streaming does not use DNS. I have seen issues where Netflix or AMmzon(on Samsung TV) can't connect to their service, just like my PCs/Mac's and once I reboot the GW, all is well. 

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Gold Problem Solver

Re: Consistent Comcast DNS Issues

Hey Folks, if you're still seeing drops in your connection and would like me to take a look, just let me know. Please send me a private message with your full name for help. Just click my name (ComcastKenF) and then on the next page, you'll see an option to send a private message on the right. 


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New Poster

Re: Consistent Comcast DNS Issues

I've been having the same issue for quite a while, at least 9 to 12 months, Thanks Comcast.

 

Wrote you a PM, well see if you can help.

 

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Re: Consistent Comcast DNS Issues

I'm having the same problem, but I can maybe add some clues. I am a comcast customer in Arizona, but spend summers in the Seattle area where I am now. The condo building where I live has plenty of comcast customers with cable service, so I have just used the "free" Xfinity wifi supplied in neighbors' modems. No problems at all until this summer. Now I experience the same "DNS" failures described here. Oddly, Facebook (via Safari) and this site will connect without trouble. For others, I have to use cell data and an iPhone hotspot.

 

My devices are 5: 2 iPhone Xs, 2 Macbooks, 1 iPad. All behave the same.

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Re: Consistent Comcast DNS Issues

I went over to my Sons house today to check and make sure it wasn't this specific laptop having issues. I had no problems at all on a Comcast provided circuit, it's his modem a real cheap 3 year old unit I bought for him it's either a Arris or Motorola modem.

 

The point is Comcast hasn't messed that modem up with their constant tinkering.

 

We went down hard here at my house about 5 PM ish and it hasn't been right since.

 

Comcast is the only company in my whole life I have ever paid to work for. I'd guess I put in at least 6 to 8 hours a month working on keeping my stuff up and running. If I can ever figure out a way to bill that company they will owe me monthly just to keep my service up.

 

I've been in networking for 23 years now, if I ran my company like they run there's everyone would hate me, oh wait everyone does hate Comcast, isn't that why they changed there name?

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New Poster

Re: Consistent Comcast DNS Issues

I am having same issues with DNS. All of a sudden browsing will not work but other apps such as Slack, Zoom and trading apps all still work.  I thought it was my computer but I switched to my other one tonight and it did it to that one.  I work from home as a trader and it has been so frustrating, having to reboot each time this happens.  It started for me in early August.  I am testing AT&T under the same conditions tonight.  I'll let you know.

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New Poster

Re: Consistent Comcast DNS Issues

The DNS issue is recurrent. Comcast tech support is clueless about what a DNS is or does. All they do is reboot your modem which doesn't resolve the problem since the problem is with their equipment. No amount of computer or modem rebooting will resolve the issue. 

  • Clueless technical support
  • Poor equipment support
  • No customer ability to direct the issue to an informed person
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New Poster

Re: Consistent Comcast DNS Issues

Ken,
You said that if we all were having the same issue to PM you.

I don’t see how to do that.

I’m having the same issue. I got a new xFi gateway last week. Ever since devices are periodically losing connections. It lasts anywhere from 5 minutes to an hour. Like the other posters, it seems to be a DNS issue as some services manage to stay connected and Windows 10 machines say they are connected to the internet even though they are unable reach anything on the internet.

This is happening 5-6 times a day to all devices at the same time.

I called Comcast support and got little help. The only suggestion was to replace the gateway.

Any help or even a suggestion of how to ask for help would be appreciated.

Russell Rowe
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Re: Consistent Comcast DNS Issues

Ken

I am having same exact problem and I am tired of having to call tech support due to connectivity issues.
I need help resolving this issue ASAP.
Thanks in advance
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Official Employee

Re: Consistent Comcast DNS Issues


@RussellHRowe wrote:
Ken,
You said that if we all were having the same issue to PM you.

I don’t see how to do that.

I’m having the same issue. I got a new xFi gateway last week. Ever since devices are periodically losing connections. It lasts anywhere from 5 minutes to an hour. Like the other posters, it seems to be a DNS issue as some services manage to stay connected and Windows 10 machines say they are connected to the internet even though they are unable reach anything on the internet.

This is happening 5-6 times a day to all devices at the same time.

I called Comcast support and got little help. The only suggestion was to replace the gateway.

Any help or even a suggestion of how to ask for help would be appreciated.

Russell Rowe
, thanks for posting here, unlocking your ability to private message me. I got your message in my personal inbox so I'll follow up there.
 
 
 
Anyone else having issues with your connection regarding xFi and DNS, please feel free to private message this account, Comcast_Support.
 
Ken

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Re: Consistent Comcast DNS Issues

@Comcast_Support Ken, I'd like to express my appreciation for paying attention to this thread. Believe it or not, I semi gave up trying to fix it and would just literally reset the routing functionality on my modem every time it happened. At the time, even change a system to a static DNS did absolutely nothing, my guess is some low level disfunction with handling packets over port 53 or maybe a faulty security mechanism but I digress. I don't think I've had to reset mine in probably over a month, so whatever the problem was seems to be resolved.

 

I'm still not happy about the lack of being able to control DNS configuration, I am trying to use my own internal DNS management in my house but since I'm not able to change it, it's created a huge headache for me. I mean, I'd like to at least be able to add internal IPs to the DNS servers handed out by DNS. I suppose that's another rant for another thread though.

 

Thanks for keeping tabs on this issue.

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Re: Consistent Comcast DNS Issues


@jhynds wrote:

UPDATE

It just happened again.

I went into the GW GUI.

I Navigated to Troubleshooting, Reset/Restore Gateway, RESET Wi-Fi ROUTER. 

This resolved the current DNS issue and it only took 90 seconds.

It does point more to the GW than any other components on the net.

It's not a FIX, but at least I can get back in the net faster. 

 


This was the exact same way I've had to resolve mine when it occurs. I haven't need to do so in a while but would definitely say this is where to start.

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Re: Consistent Comcast DNS Issues

SEEMS (?) to be fixed...!!

Ok, My old setup was the Comcast Gateway hard-wired (CAT6) to my home Router/Wifi, with EndPoints (4, including remote switches with devices) hard-wired off my Router as well as the device's Wifi Attached to the same Home Router. I added a good ($$$) Gigabit switch between my Router and the Comcast Gateway. I moved ALL hardwired endpoints (& remote switches) to the Main Gig Switch and my Routers "Wan/Internet" port is connected to the Gig switch. 

So far, for the past week, everything has been fine! If that changes I will reply to THIS message with an update. 

@dailen @RobertWy  @b_777  @CCKenF  @glmonson @bino2 @Duffyh @JimChinnis  @Tblizman@RussellHRowe ,

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New Poster

Re: Consistent Comcast DNS Issues

Same Dns errors and constant internet drops even with wired devices! Using ARRIS SURFboard SBG7580AC and for the last 30 days the internet drops multiple times during the day and constant dns error. I work from home and will end up unemployed relying on comcast internet. I just transfered service from Oregon to Houston Tx and never had any issues in Oregon 365 days! not 1 issue now i'm in Tx using the same equipment and can't get a stable connection? Tech came out today so I thought things were fixed 4 hours later down again! I call and they  claim they have to refresh my modem and all of a sudden its working again. If they would put as much effort into an fixing these issues as they do at hounding you to fill out surveys maybe so many people wouldn't be having these issues. I received over 8 calls from them today for surveys! All tech. support wants to do is discuss buying a new modem! Give me stable internet and stop disconnecting me. I'm switching to Att, this horrible service isn't for me. 

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Re: Consistent Comcast DNS Issues

 


@jhynds wrote:

SEEMS (?) to be fixed...!!

Ok, My old setup was the Comcast Gateway hard-wired (CAT6) to my home Router/Wifi, with EndPoints (4, including remote switches with devices) hard-wired off my Router as well as the device's Wifi Attached to the same Home Router. I added a good ($$$) Gigabit switch between my Router and the Comcast Gateway. I moved ALL hardwired endpoints (& remote switches) to the Main Gig Switch and my Routers "Wan/Internet" port is connected to the Gig switch. 

So far, for the past week, everything has been fine! If that changes I will reply to THIS message with an update. 

@dailen @RobertWy  @b_777  @CCKenF  @glmonson @bino2 @Duffyh @JimChinnis  @Tblizman@RussellHRowe ,


@jhynds hey I'm a IT Systems Engineer (do not work for comcast), do you know if the modem is giving out IP addresses or just the router? You may have inadvertently setup a double-NAT. Depending on your setup, that could actually cause other problems for some equipment and could actually slow everything down. I fixed internet for a client one time who was only getting 3 mbps but paying for 25 by just removing a redundant router. It really depends on the way they're configured and the type of equipment, but just FYI.

 

If you have any questions let me know, I might could help.

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Re: Consistent Comcast DNS Issues

OMG you and I both I can't believe the time I spend doing what your doing.  And, Im alone now and lost both parents.  I have much less income.  In my case neighbors can access the feed, using the xfinitywifi, and whatever they may be doing on the web can affect a paying customers gateway.  In August I was charged for a 1 TB data usage and I never used more than 300 gb if ever.

3 swapped modems starting 18 October 2019, then after the PG&E outage 4 days ending October 29 2019.   Same creepy neighbors outside using internet devices showing up on the modem as I try to retsore after 4 day power outage here.  

 

Still dealing with issue.  Comcast tech support,  all I heard was laughiong at late hours I am trying to protect my information and use my service.  They paused me.  like children, 4 days in a row I call to get anser about,  DataHarvestingRadioStart event logs on modem.  Multiple users with IP address in Africa or UK or Russia, and now my IP address has changed never happened as well as LAN.  two different addresses?  Im beyond freaked out.  Not one Tech call no response what has happened here?

Sj
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Contributor

Re: Consistent Comcast DNS Issues

Xfinity Xb6 neighbors able to utilize service August 1TB used same issue.  Agree,  NEVER been laughed at by any company I pay more than $200 a month for service and fool on the street and each low level neighbor has access to. Comcast seems angry for the paying customer to complain or receive deserverd technical resolution.  

 

Sj
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New Poster

Re: Consistent Comcast DNS Issues

Hi Ken,
I'm having problems with DNS error. Can access some sites like Google but not Amazon, ebay, my bank, etc... Not working on my phone or lap top. Please advise on how to resolve.
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New Poster

Re: Consistent Comcast DNS Issues

Hi Ken,

I also couldn't send you private message, can you unlock me as well? I'm also having intermittent connection issue with WiFi and "resolving host". Thanks.

 

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Silver Problem Solver

Re: Consistent Comcast DNS Issues


@SSGodSSVegeta wrote:

Hi Ken,

I also couldn't send you private message, can you unlock me as well? I'm also having intermittent connection issue with WiFi and "resolving host". Thanks.

 


You have to be logged into the forum under your forum name/password.  Then you have to click on the send a message link in the user's profile on the right side.  Here is a picture of a profile:Send a message-3.jpb.jpg

 


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I am just a customer, volunteering my time to help other customers here in the Forums.
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New Poster

Re: Consistent Comcast DNS Issues

I would just like to know why we humans are still physically unplugging hardware and waiting 10 seconds and plugging it back in, and pushing little buttons to reset devices, and clearing caches, and manually entering DNS's, etc, etc.  How is it that this functionality is not built-in, transparent, automatic?  Can someone PLEASE just run an AI deep-think program on all this cra p and FIX IT for once and for all?

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Regular Visitor

Re: Consistent Comcast DNS Issues

How can I send you a private message? I am experiencing DNS issues as well.

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New Poster

Re: Consistent Comcast DNS Issues

@Comcast_Support I'm experiencing what I think are the same issues as others on this thread. 

 

Current configuration:

- Arris TG1682G

- Protected Browsing Enabled

- 2.4 and 5 GHz Enabled using the same SSID

- 14 WiFi Connected Devices

- 2 Hardwired Devices

- Gateway (10.0.0.1) indicates Ethernet, Wi-Fi, and MoCA all green 

 

Observed Behavior on Windows 10 (1903):

- NSLOOKUP failures to default IPv6 Comcast nameserver 2001:558:feed::1

- NSLOOKUP failures to IPv4 Comcast nameserver: 75.75.75.75

- NSLOOKUP failures to IPv4 Comcast nameserver: 75.75.76.76

- NSLOOKUP failures to IPv4 Google nameserver: 8.8.8.8

- After 5-10 minutes all NSLOOKUP requests begin returning responses and everything starts working again

 

Other Observations:

- Rebooting the Arris Gateway also seems to fix the issue temporarily

- The problem has gotten progressively worse, occurring almost daily now

- Seeing the same connectivity problems on all WiFi and Wired devices: Android, iPhone, Synology NAS, Fire Stick, Smart TV  

 

A couple of years back, I experienced similar connectivity issues trying to enable the Parental Controls in the older gateway web interface so I gave up on and disabled them.  I'm fairly certain the user profile device assignment in the XFi App uses similar technology to block devices by MAC address.   These latest connectivity issues started right around the same time I started assigning devices to profiles.  I wouldn't be surprised if this was the root cause of the problem.

 

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New Poster

Re: Consistent Comcast DNS Issues

Hello. Like all others on this thread I am now experiencing DNS issues since changing my service.  I was not able to find a way to directly message Ken / Comcast support.

 

The only fix is to reset the router 1 to 5 times daily.  This problem just started last week.  I'm using an Arris SBG6782-AC

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Frequent Visitor

Re: Consistent Comcast DNS Issues


@gjhall99 wrote:

Hello. Like all others on this thread I am now experiencing DNS issues since changing my service.  I was not able to find a way to directly message Ken / Comcast support.

 

The only fix is to reset the router 1 to 5 times daily.  This problem just started last week.  I'm using an Arris SBG6782-AC


You know this is a long shot but you might try using DNS over HTTPS on a computer to see if it "bypasses" the issue. If the problem truly is handling of DNS by the modem then this could technically work around it on devices that can use it. It's just a theory but might provide some relief.

 

https://support.mozilla.org/en-US/kb/firefox-dns-over-https

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New Poster

Re: Consistent Comcast DNS Issues

@Comcast_Support and @CCKenF - I am also experiencing the same exact issue. Multiple times per day I lose ability to resolve DNS. Pings to 8.8.8.8 continue to work. However, when DNS resolution is down, I cannot resolve DNS even using 8.8.8.8 which is pingable. It feels like some bug in the xFI or other component that is preventing DNS resolution. 

 

What is the official Comcast solution to this problem?

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New Poster

Re: Consistent Comcast DNS Issues

Thank you for that suggestion. I am trying that out. 

 

I have already tried manually putting in Comcasts / Googles DNS servers which work for a short while then it goes back to having trouble loading page.

 

Streaming through TV / Game Consoles don't seem to have any problem. Only web browsing.

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New Poster

Re: Consistent Comcast DNS Issues

Right after my last post, I took my gateway backway back to the xFinity store and replaced it with the same model. The technician at the store activated for me in store. I took it home, hooked it up, and made sure that all internet devices were off. I turned the gateway on and then used the xFi app on my phone to connect and set it up. It automatically synced up with my old gateway name and password and configured itself. I then plugged in my three xPods and they also synced up automatically.

 

When I turned on all of the internet connected devices they were able to sign into the new gateway with no setting changes.

 

This was over a month ago and I've not had any DNS issues since.

 

I think that the keys were having the device activated at the store and setting it up with the xFi app on my phone. This did not happen with the first one. It came home without activating and I did it with support on the phone. I don't think it was configured correctly without using the app. With the second gateway, as soon as I connected with the xFI app, the app recognized me, the new gateway, and the name and password from the disconnected gatway. It then did all the configuration. This never happened with the first gateway.

 

Since then there have been no DNS or dropped connection issues.

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New Poster

Re: Consistent Comcast DNS Issues

No go on the DNS over HTTPS.    I will give their support a ring later on.

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Regular Visitor

Re: Consistent Comcast DNS Issues

Hello,

I have similer dns issues.

Started roughly 2 months ago, went on for a few days, then everything back to normal. But started again 2 weeks ago. It happens a few times per day.

At this time, I'm still connected (e.g. can still make voice call through unified comms solutions), but can't resolve any name, nslookp returns an error.

Happens on multiple laptops and smartphones at the same time (but it looks like our mac laptop still works at this moment)

We have enabled parental control (roughly at the same time when issues started without being 100% sure)

@CCKenF I saw your message but couldn't find a way to PM you...

 

It's causing big issues as I work from home, any help would be greatly appreciated.

 

Thanks,

Melanie

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New Poster

Re: Consistent Comcast DNS Issues

Ken,

Similar to these issues, I have access to sites like Google, Facebook and Comcast, but no other access. Are we able to get a static IP or help with the DNS? This is quite troublesome working from home.

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New Poster

Consistent DNS Issues

This was being addressed in this link:

https://forums.xfinity.com/t5/Xfinity-xFi/Consistent-Comcast-DNS-Issues/m-p/3228029 

 

I cannot post in this nor do I have an option to DM @CCKenF or @Comcast_Support  . This issue is driving me nuts and no one has been able to resolve it yet.

 

Any help would be greatly appreciated.

TIA

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Gold Problem Solver

Re: Consistent DNS Issues


@IT_Trevor wrote: ... This issue is driving me nuts and no one has been able to resolve it yet. ...

Are you connecting via Wifi or Ethernet? If Wifi, it's best to switch to an Ethernet cable connection if possible. That would allow you to determine whether the problem is with the Wifi signal, or with the link between your equipment and Comcast's network. Network connection problems that affect both Ethernet and Wifi devices are often due to poor coax connections, usually in or near your home.

If you want to troubleshoot this yourself, please see Connection Troubleshooting Tips. If you still need help, please provide Information Requested for Connection-Related Posts, especially downstream power levels and SNR, upstream power levels, and error log.

If you can't find the problem or you'd rather have Comcast do the troubleshooting, call them at the phone number on your bill or 1-800-Comcast, or or use one of the options on https://www.xfinity.com/support/contact-us/. If they can't fix the problem remotely, insist they send a tech out to identify the cause and correct it.

If the tech finds bad coax, splitters, amplifiers, or connections in your home (even if Comcast originally supplied them) you'll probably have to pay for the visit unless you have their Service Protection Plan (https://www.xfinity.com/support/articles/service-protection-plan, closed to customers that don't already have it). If the trouble is due to a faulty Comcast rental device, or anything outside your home, you shouldn't be charged.

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Official Employee

Re: Consistent DNS Issues


@BruceW wrote:

@IT_Trevor wrote: ... This issue is driving me nuts and no one has been able to resolve it yet. ...

Are you connecting via Wifi or Ethernet? If Wifi, it's best to switch to an Ethernet cable connection if possible. That would allow you to determine whether the problem is with the Wifi signal, or with the link between your equipment and Comcast's network. Network connection problems that affect both Ethernet and Wifi devices are often due to poor coax connections, usually in or near your home.

If you want to troubleshoot this yourself, please see Connection Troubleshooting Tips. If you still need help, please provide Information Requested for Connection-Related Posts, especially downstream power levels and SNR, upstream power levels, and error log.

If you can't find the problem or you'd rather have Comcast do the troubleshooting, call them at the phone number on your bill or 1-800-Comcast, or or use one of the options on https://www.xfinity.com/support/contact-us/. If they can't fix the problem remotely, insist they send a tech out to identify the cause and correct it.
  
If the tech finds bad coax, splitters, amplifiers, or connections in your home (even if Comcast originally supplied them) you'll probably have to pay for the visit unless you have their Service Protection Plan (https://www.xfinity.com/support/articles/service-protection-plan, closed to customers that don't already have it). If the trouble is due to a faulty Comcast rental device, or anything outside your home, you shouldn't be charged.


IT_Trevor,
 
 Got your PM. Will follow up with you there.
 -Ken

I am an Official Comcast Employee.
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