The pihole to behave as it has done for the year I have been running it given no discernible changes recently other than keeping it up to date.
I've had a Pihole set up for quite a while now and have started having major issues.
on a Raspberry Pi 3B+
I keep the pihole software up to date, running
pihole -up and
pihole -g daily.
I have a Virgin Media Hub 3 and therefore have to disable the hub's DHCP and use the pihole's one instead. That's all been working fine.
The last few days when I
ssh onto the pi (my ritual of running the updates which also includes
apt update/upgrade) it sometimes takes a while to connect.
I followed these steps with no luck: https://jrs-s.net/2017/07/01/slow-ssh-logins/
What's worse is that when I do have a ssh connection I get infrequent periods of responsiveness. The rest of the time my inputs take a long time (up to a minute) to register. I have a second raspberry pi on my local network (not running pihole) that continues to behave fine. This includes the times when the pihole is unresponsive.
On top of this I am seeing that only some of my traffic is getting blocked. For example if I click on google add (which should take my via doubleclick and therefore get blocked) I am taken to the page without it being blocked and it is not visible on the query log.
My best (limited knowledge guess) is that not all of my traffic is going via the pihole all of a sudden, though from my router's set up nothing seems to have changed.
top and the like on the pihole shows nothing of concern. Only a few % of resources are being used. The pihole is the only software running on the raspberry pi.
I have tried running the repair and I have posted the debug logs below.