Pi-hole v6 – DNS queries received but pages fail to load (Fios G3100, rate limiting issues)

Help
1

Hi all,

I’m running Pi-hole v6.5 on a Raspberry Pi (192.168.1.222, wlan0) with a Verizon Fios G3100 router (192.168.1.1). I’ve been troubleshooting a Pi-hole setup on my home network and believe I have narrowed things down significantly, but I’m still running into inconsistent behavior where DNS queries appear to succeed, yet most webpages fail to load. I say most because seemingly at random, some do load.

Setup

  • Topology: Devices → Router → Pi-hole → Internet
  • Clients are using the router as DNS (192.168.1.1), which forwards to Pi-hole
  • in the Fios router settings, I have the pihole assigned to a static ip and DNS 1 set to 192.168.1.222 (the pihole's ip) and DNS 2 set to 0.0.0.0. It only works reliably if DNS 2 is set to something like 1.1.1.1 presumably because it's able to bypass the pihole.

Issue

  • Pi-hole receives queries (visible in Query Log)
  • DNS resolution works (nslookup returns valid IPs)
  • However, webpages intermittently fail to load

Key Findings

1. Rate limiting

From FTL.log:

Rate-limiting 192.168.1.1
Still rate-limiting ... additional 1274 queries

The router appears as a single client and was being rate-limited.

2. Disabled rate limiting

pihole-FTL --config dns.rateLimit.count 0
pihole-FTL --config dns.rateLimit.interval 0
sudo systemctl restart pihole-FTL

After this:

  • DNS resolution works
  • nslookup google.com 192.168.1.222 succeeds

3. Current behavior

  • Queries show in Pi-hole
  • Responses are valid
  • Browsing still unreliable

4. Client behavior

From Windows:

Server: 192.168.1.1

Clients are still using the router as DNS.
Previously also had secondary DNS set to 1.1.1.1.

Pi-hole config (relevant)

interface = "wlan0"
listeningMode = "ALL"
dns.rateLimit.count = 0
dns.rateLimit.interval = 0
dns.blocking.active = false (for testing)

Pi-hole Diagnosis

DNSMASQ I only noticed once, but the Connection Error I saw frequently

DNSMASQ_WARN `dnsmasq` warning: Maximum number of concurrent DNS queries reached (max: 150)

CONNECTION_ERROR Connection error (**1.1.1.1#53**): TCP connection failed while receiving payload length from upstream (**Resource temporarily unavailable**)

Tests

On Pi:

dig @8.8.8.8 google.com → works
dig @127.0.0.1 google.com → works

From client:

nslookup google.com 192.168.1.222 → works

Question

Given that:

  • DNS resolution via Pi-hole works
  • Queries are visible in logs
  • Browsing still fails intermittently

Is this likely caused by the Fios router acting as a DNS forwarder (caching, fallback, or mixed DNS behavior)?

Would the recommended fix be:

  • bypassing the router entirely (Pi-hole DHCP), or
  • is there a stable way to keep the router in the chain?

Any insight into why DNS appears correct but page loads fail would be helpful.

2

From the same client, did you try nslookup google.com (without the IP)? Please post the output.

Also, please upload a debug log and post just the token URL that is generated after the log is uploaded by running the following command from the Pi-hole host terminal:

sudo pihole -d
3

Hey, thank you for the reply.

I tried nslookup google on the pihole as well as a computer on the network:

admin@pihole:~ $ nslookup google.com
Server:         1.1.1.1
Address:        1.1.1.1#53

Non-authoritative answer:
Name:   google.com
Address: 142.251.179.102
Name:   google.com
Address: 142.251.179.100
Name:   google.com
Address: 142.251.179.138
Name:   google.com
Address: 142.251.179.113
Name:   google.com
Address: 142.251.179.139
Name:   google.com
Address: 142.251.179.101
Name:   google.com
Address: 2607:f8b0:4004:c07::71
Name:   google.com
Address: 2607:f8b0:4004:c07::8b
Name:   google.com
Address: 2607:f8b0:4004:c07::64
Name:   google.com
Address: 2607:f8b0:4004:c07::66

C:\Users\me>nslookup google.com
Server:  G3100.mynetworksettings.com
Address:  192.168.1.1

Non-authoritative answer:
Name:    google.com
Addresses:  2607:f8b0:4004:c07::8b
          2607:f8b0:4004:c07::64
          2607:f8b0:4004:c07::66
          2607:f8b0:4004:c07::71
          142.251.179.100
          142.251.179.138
          142.251.179.113
          142.251.179.139
          142.251.179.101
          142.251.179.102

here is the token url:
https://tricorder.pi-hole.net/5jlDjelN/

4

Depending where exactly on the router you configured DNS settings (WAN/Internet or LAN), you most likely created/closed a DNS loop where queries originating from the router are forwarded to the router itself.
This goes on endlessly until rate limiting kicks in or resources are depleted (#concurrent connections, RAM, storage).

Preferred is to advertise the Pi-hole IP as the sole DNS server in the LAN side DHCP service settings on the router.
And leave the WAN/Internet DNS settings on factory defaults.
Some router examples below in the "Router setup" section on the left:

On the Pi, you can run below to see which DNS server(s) are advertised on your LAN via IPv4 DHCP or IPv6 RA (Router Advertisement) and by whom:

sudo pihole-FTL dhcp-discover

Or grep for them:

sudo pihole-FTL dhcp-discover | grep 'dns-server\|Recursive DNS server'

Dont post unredacted output for above ones here for privacy!