checksum
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SunOS 3.5 turns the UDP checksum off, which is legal and works
okay over interfaces such as ethernet ...
... link- level
checksumming. On the other hand, SLIP doesn't perform checksums
thus running NFS over SLIP ...
... thus running NFS over SLIP requires you to turn the UDP checksum
on. Otherwise, you'll experience erratic behavior such as the one
described above.
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