I've lost 4 hours today because of this :
( kbuernetes pod.. )

...
image: "prom/node-exporter:v1.0.0"
args:
  - --collector.filesystem.ignored-fs-types="^(tmpfs|cgroup).*$"

doesn't work ( meaning that ignored fs types param doesn't have other effect than just disabling the default value of the param ) ,
no error , nothing logged just filesystems doesn't get ignored ( i've started playing out with escaping regex, changhing other settings, changing rootfs path ecc.. )

at the end... the light

- "--collector.filesystem.ignored-fs-types=^(tmpfs|cgroup).*$"

this works..
now there are around a lot of examples and tutorial which use the format listed in the first example .. which doesn't work.. at least in kubernetes yaml definition format

( the same is valid for : "--collector.filesystem.ignored-mount-points" ( and probably for all others regexp params? )

I hope that this post could help others that with my same issue tried, I think that this should be better documented/handled because is very nasty unwanted behaviour..

thank you