[Linux-cachefs] Can cachefs be used to cache access to an NFS server which in not always on

[Antony Cleave]

I am interested in the possibility to use cachefs on a low power system
with a 2TB drive to cache access to a much larger more power hungry
system. I would like to set the large NFS node to hibernate or stand-by
after 90 mins of inactivity and have an always on cachfs node to
re-export the storage. This would require the cachefs node to be able to
wake up the nfs server if data is not in the cache using something like
IPMI or sending a Wake on LAN packet. Is such a configuration possible?
If so it would make me very happy as having my storage node on 24x7 is
probably costing me a fortune and this way it could be off 95% of the
time and automatically turn on when I need it. I don't mind having to
wait a 30 seconds or so to access files that are not in the cache.

Antony