Pi-Hole block page broken

[nayhere]

Expected Behaviour:

Pi-Hole block/whitelist page appears on blocked domains when browsing

Actual Behaviour:

On devices on the network other than my RPI - I get the standard 'Cannot connect to network' page on the browser when navigating to a blocked domain.

However if I VNC into RPI and use the built in browser on raspbian - I get the 'would you like to add to whitelist' page on blocked domains.

(I have an Airport Extreme and have tried to disable DNS rebind protection - I can't find this setting in Airport Utility could this be the probable cause?)

Thanks!

Debug Token:

65gdj2ul5b

[jfb]

You have blocking mode = NULL, which returns 0.0.0.0 for a blocked page. If you change this to BLOCKINGMODE=IP-NODATA-AAAA, you will get the blocking page back.

https://docs.pi-hole.net/ftldns/blockingmode/

Changing your default blocking mode is discussed in this link.

https://docs.pi-hole.net/ftldns/configfile/

I don't believe this is related to rebind protection. I use Apple routers and there is no setting for this; I have never had a problem.

That is curious behavior with Chromium. I tested with one of my Pi-Holes (Pi 3B+, blocking mode = NULL). When I went to a known blocked site on a client browser, I got no block page (as expected). When I launched Chromium on that Pi and loaded the same known blocked site, I got a block page (not expected).

I cleared all the caches in that browser, and when I loaded that page I got the same block page (again not expected). Running dig flurry.com from the terminal on the Pi returned 0.0.0.0 as expected.

Update - i tested Chromium again on a different Pi (same hardware) but with blocking mode = IP-NODATA-AAA. I cleared all the browser caches first and it correctly showed the block page.

[nayhere]

Thank you for that so quickly! I got thinking that the behaviour was the default from chromium.

I've edited the config file - just want to confirm that if I've never changed any of these settings previously then this file will be blank?
I've literally added 'BLOCKINGMODE=IP-NODATA-AAAA' as the only line of text in the file.

[jfb]

The default setting on a Pi-Hole install is to have a blank file there. You've done it correctly.

After you make the change, run sudo service pihole-FTL restart and FTL will pick up the changes.

[nayhere]

Excellent. I can confirm it's working now - just tested it on a few devices at home.
Thank you for all your help and speedy responses.
Hopefully the bug with chromium can be fixed!
Cheers,
Nathan

[jfb]

Check your Chromium and see if the uBlock extension is installed.