RBR850 frequently issuing DNS REFUSED responses

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Retired_Member wrote:

This is not correct, you could do a lot of changes which will remain after reboot.

 

nvram, overlay-filesystem ant more will not be erased.

 

/tmp is tmpfs and cleared each time

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Well that's good news - can you please walk me through how I can modify the parameters dnsmasq uses so that they persist each boot?

Cheer!

Something like this will do:

copy /usr/sbin/dnsmasq to /overlay/upper/usr/sbin/orbi-dnsmasq 

make a file called dnsmasq in /overlay/upper/usr/sbin (this will hide the original dnsmasq from the running os) with the following lines:

#!/bin/sh
mkdir /tmp/dns
echo "nameserver 8.8.8.8" > /tmp/dns/resolv.conf
echo "nameserver 8.8.4.4" >> /tmp/dns/resolv.conf
/usr/sbin/orbi-dnsmasq -h -n -c 0 -N -i br* -r /tmp/dns/resolv.conf -u root

Thank you for posting these instructions. I have been working with Netgear support but they jsut suggested I return the device to the store vs troubleshooting. 

I enabled telnet on the Orib and connected via the Windows built in telnet client. When I try to run the first line I get an error saying "copy: not found" 

root@RBR750:/tmp/dns#
root@RBR750:/tmp/dns# copy /usr/sbin/dnsmasq to /overlay/upper/usr/sbin/orbi-dns
masq
/bin/ash: copy: not found

Am I missing a step? 

You have to use Linux commands I believe. For example "CP" for Copy function.

May be Retired_Member can write exact commands to execute.

Yes I could do that, but I see there is a big risk for people to brick their Orbi-routers when not used to work on unix-systems.

And I would not be responsible for this, as my guide could may be missread or badly written by me :)

I have reported the bug found in dnsmasq and I hope Netgear will work on this and make a patch for everyone to install.

If you are using Windows, the easy and safe workaround is to set the DNS settings for your network connection to go directly to the DNS server IP address instead of through the Orbi.  This workaround worked for me on my Windows laptop and eliminated the intermittent DNS failures.  I used google DNS 8.8.8.8 but you can substitute your ISP's DNS address instead.

1. Hit the Windows key and search for "control panel"
2. Network and Internet
3. Network and Sharing Center
4. On the left, Change Adapter Settings
5. For each wi-fi or other network adapter used, right-click and select Properties
6. Select Internet Protocol Version 4 (TCP/IPv4) in the list and press Properties
7. The second checknox is set to Obtain DNS Server Address Automatically.  Change it to Use The Following DNS Server Addresses
8. Enter 8.8.8.8 and 8.8.4.4 (the Google DNS addresses)
9. Press OK

Now it should bypass the Orbi for DNS and go straight to the DNS servers.

Same problem with RBR750. 

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Retired_Member wrote:

Yes I could do that, but I see there is a big risk for people to brick their Orbi-routers when not used to work on unix-systems.

And I would not be responsible for this, as my guide could may be missread or badly written by me :)

 

I have reported the bug found in dnsmasq and I hope Netgear will work on this and make a patch for everyone to install.

 

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Retired_Member wrote:

Yes I could do that, but I see there is a big risk for people to brick their Orbi-routers when not used to work on unix-systems.

And I would not be responsible for this, as my guide could may be missread or badly written by me :)

 

I have reported the bug found in dnsmasq and I hope Netgear will work on this and make a patch for everyone to install.

 

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I had the same problems w/ my 750 and tried all the troubleshooting steps as well as opening a support case with Netgear. I was unable to fix the issue with DNS. 

I ended up just flipping my cable modem (Xfinity) back to router mode and set the Orbi to AP mode. You really don't lose a lot of functionality (I can still see which devices are connected to each satellite in the Orbi application) in AP mode. This fixes the DNS issue as your cable modem takes over this functionality.  Strange you have to do this for such a high end system...but the signal strength/wired satellites makes it worth keeping. 

Hi, I'm having this same problem, and am using the "workaround" for my Windows computer (bypassing the router's DNS service). I directed NG support to this forum thread so they could understand the problem. I asked for a projected resolution date for this bug, but cannot seem to get an answer. When you shared this problem with NG engineering, did they give any indication of where this bug is prioritized in their backlog? Thank you for digging into this problem!

I did not make any progress with my support case. 

If you can, flip your ISP modem back to router mode and set your Orbi to AP mode. This completely fixed the issue for me for all devices. 

5 months since this thread started and no resolution? just a workaround that only works for devices i can manually set DNS on? At least i know im not alone in this and was wondering what was the cause of all my random DNS issues. i suspected it was the router since its new but i did just move and while still google fiber, it is a new location. guess its the router. if i didnt need the coverage these 3 orbi's give, i'd go back to my trusty asus ax88u and merlin firmware

What Firmware version is currently loaded?
What is the Mfr and model# of the Internet Service Providers modem/ONT the NG router is connected too?

Whos your provider? 

Has a factory reset and setup from scratch been performed since last FW update? 

I'm on Sparklith and using a CAX80 in modem mode and RBR850 in router mode and have not seen any problems in this regard...

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Capt_Hellcat wrote:

5 months since this thread started and no resolution? just a workaround that only works for devices i can manually set DNS on? At least i know im not alone in this and was wondering what was the cause of all my random DNS issues. i suspected it was the router since its new but i did just move and while still google fiber, it is a new location. guess its the router. if i didnt need the coverage these 3 orbi's give, i'd go back to my trusty asus ax88u and merlin firmware

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FURRYe38, for what it’s worth, I have: Xfinity with a MB7621 cable modem, with the latest NG firmware (as of 11/6/20) on the Orbi ax 4200. I also have a support case open. The workaround of bypassing this router’s DNS resolution works for my Windows PCs. It also works to replace the router function altogether with a different router, but that defeats the purpose of buying this. I’ve had both my old ASUS and Google routers working with this modem/ISP and it works fine. Retired_Member has identified the bug, so it’s pretty frustrating that we can’t get a projected resolution date from NG support. If you have influence with NG, it would be great if we at least got a projected date for a bug fix.

wonky I have similar experience with NG support. Exhanged lot of emails, sent logs, phone calls with them. Finally NG support told me that they have forward to their engineering team. After that, all communication died from NG with no updates. Few days later, I received a pm from moderator of this thread. She (Bianca I beleive) was very helfull and pushed my ticket with NG support. NG support person (Sophia) called me right away who was working on my case earlier. I was in a meeting and missed her call. I informed her and even setup a time with her to talk. She claimed that she needs more information from me. She never called me during that scheduled time. Since then I am still waiting for a call from NG. Bottom line, NG is somehow refusing to acknowledge this issue.

I'm also seeing this on a RBK752/RBR750. Wired connection to PC and wireless to other devices. Webpass is my ISP. IPv6 disabled on the router. Latest firmware. Factory reset of the router. Still fails. All of my devices fail to make connections on a daily basis.

How is this not fixed after several months?

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wwxxyyzz wrote:

I'm also seeing this on a RBK752/RBR750. Wired connection to PC and wireless to other devices. Webpass is my ISP. IPv6 disabled on the router. Latest firmware. Factory reset of the router. Still fails. All of my devices fail to make connections on a daily basis.

How is this not fixed after several months?

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I believe this is an IPv6 issue, since most ISPs do not support IPv6 yet. The fix is as follows:

login to orbilogin.com / Advanced / Advanced / IPv6. I setup the following:

I chose 6to4 Tunnel on top right pull down,  Remote 6to4 relay Router set to "Auto", IPv6 Domain Name Server (DNS) Address set to "Use These DNS Servers". I chose Google's public IPv6 DNS Servers (2001:4860:4860::8888 and 2001:4860:4860::8844, you can choose other public IPv6 DNS servers). IP Address Assignment set to "Auto". Tested using test-ipv6.com

As soon as I correctly setup IPv6, and passed the tests, I no longer see any DNS issues.

If you choose not to do this setup, and want to keep IPv6 disabled in your Orbi, you can go into your PC or laptop network settings and enter public IPv6 DNS servers. This also stops the errors on each individual PC or laptop. 

https://community.netgear.com/t5/Orbi-AX/Intermittent-DNS-Errors-and-WiFi-Issues/m-p/2018127/highlight/true#M10111

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wwxxyyzz wrote:

I'm also seeing this on a RBK752/RBR750. Wired connection to PC and wireless to other devices. Webpass is my ISP. IPv6 disabled on the router. Latest firmware. Factory reset of the router. Still fails. All of my devices fail to make connections on a daily basis.

How is this not fixed after several months?

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i fixed this by returning it to best buy and going with the asus zenWiFi AX. not only was it cheaper but it doesnt have this DNS issue. i was having way too many of these DNS hiccups across many devices. 

Let us know if MstrBigs suggestion helps. 

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wwxxyyzz wrote:

I'm also seeing this on a RBK752/RBR750. Wired connection to PC and wireless to other devices. Webpass is my ISP. IPv6 disabled on the router. Latest firmware. Factory reset of the router. Still fails. All of my devices fail to make connections on a daily basis.

How is this not fixed after several months?

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Yeah, I'm fixing mine by returning to Costco as soon as the new Unifi 6 APs I ordered arrive.

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pinchweasel wrote:

Yeah, I'm fixing mine by returning to Costco as soon as the new Unifi 6 APs I ordered arrive.

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I wish I ordered from Costco so I had that option I ordered from Bestbuy.    Really disappointed in Netgear and I haven't recommended this Product to anyone who has asked me.   What exactly did I pay a premimum for?  Never again.

Good Luck then. 

Mines working, with out the IPv6 configuration. 

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pinchweasel wrote:

Yeah, I'm fixing mine by returning to Costco as soon as the new Unifi 6 APs I ordered arrive.

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We won't use Ubiquiti model in our installs. Coverage and speed are limited. I hope your results differ.