/etc/resolv.conf on /dev/loop10 with 98% Usage

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1

Hi,

I'm running pihole docker with 4GB of disk and the /etc/resolv.conf running on /dev/loop10 is filling up very fast and when it reaches 100% pihole stops working properly.

Could it be caused by DNS cache insertions?

My current DNS cache size is 100K and DNS cache insertions now is around 900K.

root@home-dns2:/var/log/pihole# df -h
Filesystem      Size  Used Avail Use% Mounted on
overlay         3.9G  3.6G   78M  98% /
tmpfs            64M     0   64M   0% /dev
tmpfs           3.7G     0  3.7G   0% /sys/fs/cgroup
/dev/loop11     2.1G   16K  2.0G   1% /iox_data
tmpfs           3.7G  133M  3.6G   4% /dev/ttyS3
/dev/loop10     3.9G  3.6G   78M  98% /etc/resolv.conf
shm              64M   57M  7.6M  89% /dev/shm
devtmpfs        3.7G     0  3.7G   0% /dev/tty
tmpfs           3.7G     0  3.7G   0% /proc/acpi
tmpfs           3.7G     0  3.7G   0% /sys/firmware

Debug: https://tricorder.pi-hole.net/qLjoxqVa/

2

This isn't a Pi-hole issue.
You'd have to look into processes that are allowed to dynamically update /etc/resolv.conf.

Pi-hole neither reads nor writes that file.

3

Also, these partitions are in your host OS.

Your root partition (/) is 98% and apparently /dev/loop10 is the same partition:

You need to find out what service is writing to this partition.

4

You've mounted a loop partition as a file, /etc/resolv.conf is a file, not a directory.

Edit: And you've also mounted a tty in as tmpfs?

tmpfs 3.7G 133M 3.6G 4% /dev/ttyS3

Are you using docker-compose or another orchestrator? What is the compose file contents or the docker run command you are using. What do you have for the host systems /etc/fstab?