Ways to Monitor NFS Calls from Client

[Lee Eric <openlinuxsource at gmail dot com>]

Hi,

I'm not sure if this topic had been raised previously. I am exploring
some ways to monitor NFS calls from client side. So I checked
https://sourceware.org/systemtap/examples/io/nfs_func_users.stp and
https://sourceware.org/systemtap/tapsets/nfsd.stp.html. However, that
makes me confused that because both does not work(or maybe the way I'm
using is wrong).

For the first one there's no output when client access files on NFS
server. For the second one I wrote a very small and simple stp:

probe nfs.proc.open {
    printf("Opening file %s from server %x\n", filename, server_ip)
}

Still, if I access any files there's no output either.

So I'm curious is there any actual way to capture NFS calls from
client side via SystemTap? Also, for the second method, any way to get
other NFS calls like GETATTR, READDIRPLUS etc.?

Thanks.

Hui