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If you are Experiencing issues with a Pi-hole install that has non-standard elements (e.g you are using nginx instead of lighttpd, or there is some other aspect of your install that is customised) - please use the Community Help category.
Expected Behaviour:
[Updated from stretch to bullseye as stretch now not supported]
Actual Behaviour:
[pihole has stopped blocking ads and the dash does appear, but none of the stats are working after update]
Unfortunately after updating to Bullseye from Stretch, Pihole has stopped working, which was fine before the update. I have uploaded the debug log which might indicate the isssue could be to do with 'No IPv4 address(es) found on the eth0 interface'.
I am not knowledgeable at all on the subject, so hopefully someone might be able to help with the issue.
Bullseye changes the network interface names, but they don't make this obvious.
Where before, your interface was: eth0, and this is what your Pi-hole is currently configured for.
After Bullseye, this is changed to (specific to each device, your specifics shown): enxb827ebb7f74b. This is an interface followed by the MAC of the device. Since the name of the interface changed, Pi-hole doesn't know it yet.
This is predictable network interface name, and you can change this behavior if you run:
sudo raspi-config and go to the Advanced options selection.
