Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!iuvax!uxc.cso.uiuc.edu!tank!mimsy!chris
From: chris@mimsy.UUCP (Chris Torek)
Newsgroups: comp.unix.questions
Subject: Re: NFS
Message-ID: <18739@mimsy.UUCP>
Date: 25 Jul 89 22:54:14 GMT
References: <20365@adm.BRL.MIL>
Organization: U of Maryland, Dept. of Computer Science, Coll. Pk., MD 20742
Lines: 23

In article <20365@adm.BRL.MIL> mchinni@pica.army.mil
(Michael J. Chinni, SMCAR-CCS-E) writes:
>Systems: s1 DEC VAX 8600 ULTRIX 3.0
>	 s2 GOULD PN9080 UTX/32 2.0u03
>... the dump tape format of s1 and s2 are NOT compatable

Correct; dump tapes are machine dependent.  Use tar or cpio for machine
independent backups (tar will not back up device special files, which
is proper---special files are machine dependent0---and will fill holes,
which is sometimes but not always bad).

>NFS mounting lets us use s1 dump to dump s2 filesystems, and use s2 dump to
>dump s1 filesystems.

This is misguided.  Dump reads the raw device-special file, which is why
it and its tapes are machine-dependent.  It does this for speed.

It is usually possible (and sometimes even easy) to jury-rig restore so
that it can restore dump tapes made from other systems.  The 4.3BSD-tahoe
restore can read Sun dump tapes.
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7163)
Domain:	chris@mimsy.umd.edu	Path:	uunet!mimsy!chris