bug#47706: nfs mount in file-system works only if "nfs4" type is used for "mount" syscall

[Maxim Cournoyer]

Hello,

fsdfsdfsd3 <fsdfsdfsd3@protonmail.com> writes:

> Hello,
>
> I ran into an issue with trying to mount an nfs file-system in an 
> operating-system config.. I managed to trace it back to being an issue with 
> the mount syscall.
>
> The following did not work:
> (mount "192.168.1.10:/nas-server" "/mnt/nas-client" "nfs" 0 "addr=192.168.
> 1.10")
> and would result in an error "No route to host"
>
> I changed the type from "nfs" to "nfs4" however and this did work (For 
> context; at the command line, both mount.nfs and mount.nfs4 also work fine., 
> mount.nfs also works fine without nfs-utils installed).
>
> This might be fixable by adding another check-procedure option for "nfs4" in 
> addition to nfs, but I am sending it your way in case there is something else 
> going on.
>
> Thank you!

Does this really work?  I seem to recall that the bigger problem would
be that file system services do *not* and cannot currently depend on
networking (while NFS obviously does).

Here's the attached output of

$ guix system shepherd-graph gnu/system/examples/bare-bones.tmpl \
  | dot -Tsvg -oout.svg

out.svg
Description: Binary data

We can see that the networking service dependency chain has:

networking --> user-processes --> user-homes --> file-systems

Which to me suggests that it wouldn't be enough to fix the problem you
reported above (or perhaps it is?  and NFS would simply fail during the
boot but keep trying until networking becomes available without too much
of an issue?)

Thanks,

Maxim