How to t/s intermittent faults/hickups?

[voytek]

I have been running pi-hole since about a year, first on CentOS, now on RPI 4, what a brilliant concept, does what's written on the box, love it!

Pi-hole [v5.17.2] FTL [v5.23] Web Interface [v5.20.2]
Current stats
Total queries 27,519 14 active clients
Queries Blocked 6,988 List blocked queries
Percentage Blocked 25.4% List all queries
Domains on Adlists 153,801 Manage adlists

I use 4 additional adlists
Steven Black
Perflyst PiHoleBlocklist master SmartTV.txt
WaLLy3K (About ¦ Firebog)
d3ward

Overall, it just purrrrrs along, no real issues, in fact, no issues.

But, lately, on Samsung TV, when I hit Home button, sometimes, seldom, I get Samsung's advert to the left of home icon on screen, either with colour image, or, blank background.
When I've tried to action that, got an image/ icon on screen (that I can't duplicate now, sorry) that won't load anything, times out.

How can I research/troubleshoot such intermittent issue

When I saw it last week, I running multi hour imapsync process, 20gb transfer, so at first I thought I was maxxing out RPI - though, top load average was below .2, but even after imapsync finished, still had that issue

Any thoughts?

[chrislph]

It's normal to find that even when an advert is blocked, the 'container' which holds it is still rendered. In your case it looks like sometimes an advert is loaded, and you see the image in there, or the advert is blocked and the container just displays a blank background. It is analagous to how sometimes on a web page you see a big blank area where the advert would have been if Pi-hole hadn't blocked it.

If you've never seen this behaviour until now it may be that Samsung have updated the TV's OS and this is the new behaviour. Perhaps it tries to display an advert every few times you return to that screen, causing you to see the container.

I found another Smart TV blocklist which has a few extra Samsung ad-related domains which the Perflyst one doesn't have, and it seems to be maintained, so perhaps newer ad domains introduced by Samsung are being blocked. Worth adding to the mix to see if it helps. If so, it would prevent the images appearing, but the blank container with Ad written above it I think is going to keep showing up now and again.

https://raw.githubusercontent.com/hkamran80/blocklists/main/smart-tv

[voytek]

thanks for detailed explanation, and, the analogy,

I guess as it happened to coincide when I was running some 'heavy' work over several days, I assumed, wrongly, I was overloading, etc, etc. I just got used to it being so reliable and error free...
I guess nothing is maintenance free... I need to stay abreast of latest lists, etc...
I've added the suggested list hkamaran80 list

thanks again, much appreciated!