multiple client root partition bug

[Paul Davis]

I have today just finished a conversation with a member of Sun's technical
support team in the UK concerning the following problem:

	A client that is supposed to be served by a SunOS4.0 server
	*apparently* booted from a SunOS3.4 server. The latter does
	NOT have a file in /tftpboot corrresponding to the clients
	IP address, but did once serve as an nd server to the client
	when it ran 3.4. The nd.local file on the 3.4 server still
	contains an entry for this machine.

What I have been told I find amazing/ridiculous/hard-to-believe. If you
have more than one possible source of a client's root partition on the
network (e.g. local disk, SunOS4.0 server, nd server ...) then even though
the client will boot the correct kernel, there is no guarantee where it
will get its root partition from. This was deemed a feature rather than a
bug.

Its not terribly obvious when this has happened that it has - all the
common checks for version (/etc/motd, "strings /vmunix") work on disk
files, not the kernel in memory. Moreover, having a 4.0 kernel and a 3.4
filesystem is not disastrous, but does lead to problems ...

Has anyone else come across this (as Sun claim to have done) or have any
comments on its bletcherousness ?

thanks

Paul

	Paul Davis at Schlumberger Cambridge Research
	<davis%scrsu1%sdr.slb.com at relay.cs.net>