Skip site navigation (1)Skip section navigation (2)
Date:      14 Nov 1999 14:45:52 +0100
From:      naddy@mips.rhein-neckar.de (Christian Weisgerber)
To:        freebsd-questions@freebsd.org
Subject:   Re: dump -a
Message-ID:  <80meeg$s8k$1@bigeye.rhein-neckar.de>
References:  <13D5F9EDFD72D211BC3100105A1C22330549E5@akira.lanfear.com>

next in thread | previous in thread | raw e-mail | index | archive | help
Marc Wandschneider <MarcW@Lanfear.com> wrote:

> 	how good is the -a switch on the dump command?

Very good. It's pretty much required for painless backups if you
want to put several archives on a single tape or have a drive with
compression.

> 	I've got a 12/24GB Sony 4mm SCSI DAT drive, and was wondering if
> I had to enter all the density/length commands,

That's pretty futile. If you end up having to specify the capacity
of the tape, do yourself a favor and use blocks ("-B") rather than
the arcane density/length options.

> or if the dump command would figure it out on it's own.

That's actually not a question of dump figuring it out but rather
of the tape driver properly returning a short write. sa(4) apparently
does for my Wangtek 51000HT (QIC-1000).

> Under Linux, we had no such luck,

Until rather recently, the Linux port of dump didn't support "-a"
at all. Version 0.4b9 certainly does. I don't know whether the
Linux tape driver is up to it, but using rmt on a remote host, "-a"
works.

-- 
Christian "naddy" Weisgerber                  naddy@mips.rhein-neckar.de



To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-questions" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?80meeg$s8k$1>