Re: NFS re-write, RPC library and some more scripts

[David Fifield <david () bamsoftware com>]

On Mon, Jan 25, 2010 at 09:42:38PM +0100, Patrik Karlsson wrote:
> I received a bug report from Matt regarding nfs-showmount not properly
> listing the exports from a server. Having a look at one of my first
> scripts kind of made me sick. So I re-wrote it from scratch and
> factored out all the RPC/NFS code into a library called rpc.lua.
>
> The bug was most likely related to the output from the server being a
> lot larger than the two entries I had in my test environment. The
> mountd program can be queried over either udp or tcp and the script
> was doing both. When the answer gets large enough it will only work
> over tcp, which brings me to the next bug, the fact that I was only
> reading from the socket ones. Obviously a larger export list wouldn't
> be read into the buffer with a single read. 
>
> Both of theses issues are addressed in the new code and Matt has been
> able to confirm that the script works now. Hopefully my last minute
> changes didn't change that.
>
> In the works of creating the library I implemented a couple of more
> rpc calls and added two more scripts: nfs-get-stats and
> nfs-get-dirlist. The first script gets disk usage statistics of from
> each share and the second script lists the first 10 items in the
> shared directory.

For these two I would suggest removing the "get" from the script names.
Even with that, nfs-statfs might be better because that's the name of
the NFS procedure--with the name "stats" I was at first expecting to
information like number of accesses and time of last access. Just for
the benefit of other readers, here is what the output looks like:

-- Host script results:
-- | nfs-get-stats:
-- |   /home/storage/backup
-- |     Block size: 512
-- |     Total blocks: 1901338728
-- |     Free blocks: 729769328
-- |     Available blocks: 633186880
-- |   /home
-- |     Block size: 512
-- |     Total blocks: 1901338728
-- |     Free blocks: 729769328
-- |_    Available blocks: 633186880

I tried the scripts. nfs-showmount is still working for me, but
nse-get-dirlist and nfs-get-stats don't work (produce no output) against
Mac OS X nfsd. I traced the problem to the call

        local mountd_ports = getPortsForProgram(host, "mountd", 2)

which is returning an empty table. It works with version 1 in
getNfsExports, but not version 2. Is this just a limitation of the nfsd,
that it can't provide this information?

A packet trace of the scripts running seems to indicate that results are
returned for mountd version 1 and 3, but not 2.

David Fifield
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