SparcStation 1 Networking problems

[Stephen Corbesero]

I am having some trouble with a sparcstaion on our network, and I'd
like some external advice and suggestiosns.  We have a sparcstation 1
which serves some nfs disk to various machines, although none are
diskless clients.  The system is running SunOS 4.0.3, has 8mb of
memory, a 600mb scsi drive and two internal 200mb scsi drives.  Over
the last month or so, the system has been "sluggish" on the net.
NFS/RPC requests often time-out, and it reports 6-48% packet loses
during ping tests.  I have already exchanged ethernet cables, but
that has no effect.  The "limited" hardware diagnostics report that
ethernet interface is ok, and the cpu seems to be working fine.  I've
sat in front of it several times now watching various system
activites, but can't find anything going on.

There seems to be no direct relationship to the sluggish behavior and
any monitorable system events.  I've already regenerated the kernel
with a greater number of users, but that does not seem to have had any
effect, either.

I could use any information at this point.   Thanks in advance.