I have found my dockerd failed to start recently. I have traced logs and found that in
/lib/systemd/system/containerd.service it has a pre start command
modprobe overlay. Actually I’m using
devicemapper. So I’m confused, is module overlay always required even not using overlay as storage device?
BTW, I have found a interesting thing. overlay is existed when I run
lsmod but not found when I run
modprobe overlay. Could anyone tell me what’s going on?