Pi-hole blocking internet access for whole network

[jfb]

@Cas

Server: 8.8.8.8

This client is not using Pi-hole for DNS. It is using Google DNS.

[deHakkelaar]

@Cas

Nslookup pi.hole 192.168.2.15

Server: 192.168.2.15
Address: 192.168.2.15#53

Name: pi.hole
Address: 192.168.2.15

This is a good result.
Now try proceed with below to finalize:

https://docs.pi-hole.net/main/post-install/

And disconnect/reconnect a test device from network so the changes propagate.
And test again on the test client with:

nslookup pi.hole

[Cas]

When I setup my phone to use pihole, my phone works. It uses pihole and it has access to the internet. When I do the nslookup commands, i get the same result as that I posted a few comments before.

But when I setup the pihole in the router, it blocks access to the internet. And it still gives the same results from nslookup.

I get these results from every setup (only phone, connected to pihole and access to the internet; the whole network, not access to the internet):

@Cas

> Nslookup pi.hole

> Server: 8.8.8.8
> Address: 8.8.8.8#53
>
>
>
> ** server can't find pi.hole: NXDOMAIN

> Nslookup pi.hole 192.168.2.15

> Server: 192.168.2.15
> Address: 192.168.2.15

[DanSchaper]

Do you mean for Pi-hole to be 192.168.2.15 or 192.168.2.1?

Edit: Or did you leave off the last 5 on the quote?

[Cas]

Piholes ip adress is 192.168.2.15
Gateways adress is 192.168.2.1

[Cas]

Didn't quote properly

[DanSchaper]

@Cas

> Nslookup pi.hole 192.168.2.15

> Server: 192.168.2.15
> Address: 192.168.2.15

If that's what you see on all the clients then Pi-hole is working on all the clients. Only Pi-hole knows what pi.hole is and can turn that in to an IP address.

If things fail when putting 192.168.2.15 as the DNS in the router then you need to look to see why the router is not using it. Could be something like a firewall, could be something like Rebind Protection, could be a whole lot. I don't think you've ever said what the router is?

[Cas]

Router model: Arcadyan VGV7519

I have never had this problem. So what should I change in the router settings. This only happened after updating to the newest version of pihole...

[deHakkelaar]

Have you setup the router DHCP service like described in that doc I posted earlier ?
If not and configured the WAN/Internet DNS settings to point to Pi-hole, you might experience some kind of router security feature like rebind protection that DanSchaper mentioned earlier:

Why won't Pi-hole work with DNS rebind protection enabled?

What is DNS rebind protection? If your router has an option called DNS rebind protection enabled, you may run into issues when trying to use Pi-hole as your DNS server. The reasons for this are quite technical, but to summarize what this option does in one sentence: DNS rebind protection does not allow DNS queries to be answered with a local IP address. Why does this interfere with Pi-hole? DNS rebind is meant to be a countermeasure to an attack on your network. So in many cases, it's ac…

The end goal is to have a response similar as below on a client:

C:\>nslookup pi.hole
Server:  ph5
Address:  10.0.0.4

Name:    pi.hole
Address:  10.0.0.4

---

C:\>nslookup flurry.com
Server:  ph5
Address:  10.0.0.4

Name:    flurry.com
Addresses:  ::
          0.0.0.0

EDIT: Dont run nslookup in a Termux session on Android!
Termux always default uses Google's public DNS service at 8.8.8.8 if not specify a DNS server.
For Android you can install the "Network Info" app that up till now reliably shows DNS servers configured.

[Cas]

I... was using termux on my phone. I didn't know termux uses 8.8.8.8 instead of the used dns.

I couldn't find any setting in my router that had to do with disabling rebind protection.

I will try the nslookup thing on my computer (win10).

Should I try after that, to uninstall pihole and install an older version? As this problem only came forward after updating... Using the second newest version should work perfectly as it only stopped working after updating the the newest version.

[jfb]

@Cas

Should I try after that, to uninstall pihole and install an older version?

No. It is highly likely the problem is not related to the Pi-hole version.

[Cas]

On my windows 10 pc, with the (only) dns server setup as 192.168.2.15 as seen below using ipconfig /all.

========================================
The first command and output:

@deHakkelaar

The end goal is to have a response similar as below on a client:

C:\>nslookup pi.hole
Server:  ph5
Address:  10.0.0.4

Name:    pi.hole
Address:  10.0.0.4

These outputs match so that's good.

==============================================
The second command and output:

@deHakkelaar

C:\>nslookup flurry.com
Server:  ph5
Address:  10.0.0.4

Name:    flurry.com
Addresses:  ::
          0.0.0.0

These also match so that's also good.

Both commands were done only with my pc using pihole. These commands were not done using pihole as dns server in the router settings.
Do you also want the nslookup outputs when pihole is setup as dns server in the router settings (the outputs now are when only my pc is connected to pihole) or is this enough?

[jfb]

@Cas

Do you also want the nslookup outputs when pihole is setup as dns server in the router settings

Yes, because this appears to be the configuration that is causing problems.

[Cas]

Following commands and ouputs were while pihole was setup in the routers settings as dns server and the only server (others were 0.0.0.0).

[Cas]

Strangely enough, it is working now. I have pihole setup as the only dns server in the router settings and I have internet access. I did nothing. Just changed the dns server from standard to pihole, and it isn't blocking now... I haven't changed anything in any settings. Since the problem started, I haven't changed any settings in the router or pihole. All I have been doing was switching between 1.1.1.1 and 192.168.2.15 in the router dns settings, for when you guys had questions or asked to do something. Everytime I changed to 192.168.2.15, internet access was blocked. Now I change it, and it isn't blocked. A great mystery why it is working now...