barmar@think.com (Barry Margolin) (06/07/90)
I was having trouble with a Symbolics Lisp Machine that was trying to write
a file on a SunOS 4.0.3 file server using NFS. The I/O board on the LispM
was a bit flaky (I've since replaced it) so it was dropping some incoming
packets. In particular, it frequently dropped the reply to its NFS Write
RPC packets. It retransmitted the packet, but the Sun never replied to the
retransmitted packet at all (I was watching with a network monitor), and
eventually the LispM would report a timeout. This doesn't seem like
appropriate behavior for the server. I assume the server is maintaining a
cache of recent writes in order to improve idempotency, but the right thing
for it to do when it sees a duplicate write request is to send out another
reply without actually rewriting the block, but it shouldn't ignore the
request completely.
Does anyone know if my suspicion about the cause of the problem is correct.
Does 4.1 still have this behavior?
--
Barry Margolin, Thinking Machines Corp.
barmar@think.com
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