Windows PC suddenly Showing Ads; Pi-Hole is only DNS Server

[murray.richardt]

Expected Behaviour:

Set up Pi-Hole about 4 months ago as the only DNS Server and has been blocking ads on all connected devices flawlessly (until now).

Actual Behaviour:

This morning my work PC (Dell Precision Laptop) would not connect to the internet upon startup. Had to reboot and reconnect to the internet (initially "connected with no internet"). During the process, I used the windows network diagnostics tool. After reestablishing the network connection and regaining internet access, ads started showing up. I searched here and reddit and found some ideas, but none worked for me. I toggled the auto/manual DHCP settings (at least I think I did?), and I also flushed the DNS Resolver Cache. Any help is most appreciated.

Debug Token:

Your debug token is: https://tricorder.pi-hole.net/u9ct6kfnit

[DanSchaper]

Can you do a quick pihole -v and post the results? It looks like you are on some old versions of the Pi-hole components.

Edit:

Also, it looks like your DHCP server is handing out 10.0.0.1 as the DNS server and Pi-hole is on a different IP address.

*** [ DIAGNOSING ]: Discovering active DHCP servers (takes 10 seconds)
   Scanning all your interfaces for DHCP servers
   Timeout: 10 seconds
   
   * Received 548 bytes from eth0:10.0.0.1
     Offered IP address: 10.0.0.19
     Server IP address: N/A
     Relay-agent IP address: N/A
     DHCP options:
      Message type: DHCPOFFER (2)
      server-identifier: 10.0.0.1
      lease-time: 86400 ( 1d )
      netmask: 255.255.255.0
      router: 10.0.0.1
      dns-server: 10.0.0.1
      --- end of options ---
    
   DHCP packets received on interface eth0: 1
   DHCP packets received on interface lo: 0
   DHCP packets received on interface wlan0: 0

*** [ DIAGNOSING ]: Setup variables
    PIHOLE_INTERFACE=eth0
    IPV4_ADDRESS=10.0.0.6/24
    IPV6_ADDRESS=
    PIHOLE_DNS_1=8.8.8.8
    PIHOLE_DNS_2=8.8.4.4
    QUERY_LOGGING=true
    INSTALL_WEB_SERVER=true
    INSTALL_WEB_INTERFACE=true
    LIGHTTPD_ENABLED=true
    CACHE_SIZE=10000
    BLOCKING_ENABLED=true

[jfb]

On the PC, from the command prompt or terminal on that client (and not via ssh or Putty to the Pi), what is the output of

nslookup pi.hole

[murray.richardt]

Hey folks - thanks for the replies. I'm not a networking guy, so setting this up (along with my NAS) was a learning experience for me and I'm really flirting with the edges of my knowledge on this one, so I appreciate your input (and patience)....

DanSchaper, I usually use the GUI interface with the Pi. I think the version info you're looking for is here:

10.0.0.1 is my router (Netgear Orbi) and it looks like it's been set as the DHCP Server since I set this up:

Should I disable the router as the DHCP and switch to the Pi?

jfb : Here's the output you requested:
Microsoft Windows [Version 10.0.19042.928]
(c) Microsoft Corporation. All rights reserved.

C:\WINDOWS\system32>nslookup pi.hole
Server: localhost
Address: 127.0.0.1

Name: pi.hole
Address: 10.0.0.6

[murray.richardt]

UPDATE:
The offending PC is not showing ads today.
If anyone can offer feedback or suggestions on what's been written upthread and can prevent these hiccups in the future or generally increase the stability of my setup, I'd be very grateful.
Rich