The 3Com 3c400 (ec) Multibus Ethernet card can only buffer two
received Ethernet packets, regardless of their length, before it starts
dropping packets. Unless overridden, an NFS client read requests 8
kilobytes at a time. This means six or more packets will be sent by
the server, usually quickly enough to fill the card and cause the third
and subsequent packets to get dropped.
NFS has an all-or-nothing mentality about it, so the client will throw
away any packets it did get and just send the request again, making
for a vicious cycle. The solution is to tell NFS to only request 1
kilobyte at a time, done by adding an option to the client's mount command:
mount -t nfs -o -r=1024 server:directory mountpoint
