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Re: [MiNT] Firebee Coldfire MiNT Kernel and NFS
On 02/09/2014 19:56, Vincent Rivière wrote:
Next step.
Another use case:
Linux client to FireBee server
On Linux, I use:
mount -t nfs 192.168.0.129:/ /some/path -o rw,vers=2
It works extremely *fast* and *reliably*.
However, by looking at the sniffer, I see that it uses TCP. This is another
point in favor or Markus theory.
So I tried UDP:
mount -t nfs 192.168.0.129:/ /some/path -o rw,vers=2,udp
The UDP usage is verified with the sniffer.
With UDP, basic operations work fine and fast, but bigger operations times
out. There is a problem.
By looking at the sniffer, I see duplicates from the FireBee.
And I think I found an interesting clue:
The duplicate packet is exactly 1500 bytes, it is the first one of a
fragmented frame. This is confirmed by looking at the data.
But strangely, I never see the second packed, among the many duplicates.
So I believe there is a problem in mintv4e.prg, when sending big UDP frames
which are fragmented: the second and others are not sent. Once again, this
reminds me the UDP checksum routines. I will check them next.
As a summary, on the FireBee:
- The NFS client fails due to huge timeouts, but works better when there is
screen activity.
- The NFS server is unreliable in UDP mode.
--
Vincent Rivière