backups on the 7300/unix-pc

Wed Jan 18 18:10:42 AEST 1989

In article <4636 at sfsup.UUCP> grk at sfsup.UUCP (G.R.Kuntz) writes:
>I guess it's time to do backups :-(.
>
>...Does anyone have a simple scheme (akashell script) that might do this?
>
>			Ralph (attunix.sf.att.com!grk)
>-- 
>	G. Ralph Kuntz N2HBN	grk at attunix.att.com

[I decided to post this message as a followup article, rather than sending
it to Ralph directly, just to save him the bother of re-posting it himself.]

Here's the script I wrote for the purpose a while back.  It doesn't handle
compression, but I believe it would not be hard to add it to the script.
This past summer, Steve Spearman (ihnp4!ihopa!ihop3!booboo!spear) used the
following line in a shell script to do compressed backups he posted to
unix-pc.sources (4 Jun 88):

		cpio -co < $tmp 2> /tmp/ccpio.$$2 | compress |
			dd of=/dev/rfp021 obs=1024 count=$SIZE 2>/dev/null

(I don't understand where Steve gets the magic number 1024 for the output
buffer size, but the strategy looks fairly straightforward, and wouldn't
be hard to integrate into what I offer below, though I am reluctant to do
so yet myself, since I have discovered that already-compressed files which
get compressed again as part of a archive fed to a process via a pipeline
tend to mess things up to the extent that it seems to confuse compress, and
it comes out compressing things in such a way as to not save much space.)

What I did to get things going was to use TOUCH(1) to place an explicit
timestamp (Oct 1, when I originally installed the 3.51 software) on all my
original distribution files, and, after adjusting permissions, did a dump
of them.  I then did what I call a "pseudo-epoch" (epoch being a term that
comes from DUMP(8) found in many UNIX implementations to refer to a level
zero dump) of only those files in the "sys" category (defined in the script
as excluding a bunch of directories) newer than those I had previously
timestamped.  For all other disk areas, I did a simple epoch.  For each
epoch or pseudo-epoch, there is a timestamp file created in the directory
/etc/dumpdates:

	-rw-r--r--  1 root     0 Nov 28 00:10 epoch.gst
	-rw-r--r--  1 root     0 Dec 26 01:59 epoch.guest
	-rw-r--r--  1 root     0 Nov  7 02:12 epoch.local
	-rw-r--r--  1 root     0 Aug 19 00:00 epoch.news
	-rw-r--r--  1 root     0 Dec 11 11:56 epoch.sys
	-rw-r--r--  1 root     0 Oct  1  1987 epoch.sysabs

I also keep a log of what I've dumped in this same directory:

	-rw-rw-r--  1 root  6030 Jan 14 16:32 dumplog

which has the following sort of content:

	idump	local	Mon Dec 26 01:37:03 EST 1988
	idump	news	Mon Dec 26 01:48:04 EST 1988
	idump	gst	Mon Dec 26 01:53:39 EST 1988
	edump	guest	Mon Dec 26 01:59:54 EST 1988
	idump	sys	Mon Dec 26 02:06:31 EST 1988
	idump	gst	Mon Jan  2 16:31:16 EST 1989
	idump	news	Mon Jan  2 16:37:52 EST 1989
	idump	local	Mon Jan  2 16:40:53 EST 1989
	idump	sys	Mon Jan  2 16:46:23 EST 1989
	idump	gst	Sat Jan 14 16:09:49 EST 1989
	idump	sys	Sat Jan 14 16:32:52 EST 1989

The script goes (via a link) both by the name "edump" (epoch) and "idump"
(incremental).  It takes a single argument, that being the name of the disk
"area" you want to dump.  For example, I typically do something like the
following on a regular basis:

	idump local
	idump news
	edump guest	(there's not much there, so I do an epoch dump)
	idump gst
	idump sys	(this one's last so that the timestamp files from
			 today's dumps in /etc/dumpdates are saved)

Here is the script itself.  I welcome any feedback or improvements people
would like to offer, and will gladly repost the results to unix-pc.sources.
Since Ralph asked the original question about dumps, he's still the best one
to whom to send other solutions to the overall dump question.  I'll look
forward to his summary of these other solutions, so that perhaps we can
take the best of each and fabricate something really spiffy!

---------------------------------(cut here)------------------------------------
if [ $# != 1 ]
then
	echo "usage [ei]dump type"
	exit 1
fi

ddroot="/etc/dumpdates"

if [ $0 = edump ]
then
	if [ $1 = sys ]
	then
		newer=-newer
		ddfile=$ddroot/epoch.sysabs
	fi
else
	newer=-newer
	ddfile=$ddroot/epoch.$1
fi

if [ -n "$newer" ]				# incremental or sys epoch
then						# newer than what?
	if [ ! -f $ddfile ]
	then
		echo "cannot locate timestamp file for dump of $1"
		echo "$ddfile"
		exit 2
	fi
fi

exclude=\'\'		# initially null

p1=.
p2=
case $1 in
sys)
	path=/
	exclude='^dev|^u/g|^u/src|^usr/local|^usr/spool|^tmp|^usr/uucppublic|^usr/man|^lost\+found|^usr/preserve|^usr/lib/news|^usr/adm|^usr/bin/DOS|^usr/mail';;
gst)
	path=~gst
	exclude='^\.files|^\.nfiles';;
src)
	path=~src;;
news)
	path=~gnews/News;;
guest)
	path=/u/g;;
local)
	path=/
	p1=/usr/local
	p2=/usr/man;;
*)
	echo "dump keyword $1 invalid"
	exit 3;;
esac

cd $path
find $p1 $p2 $newer $ddfile -depth -print	| sed 's/^\.*\///' \
						| egrep -v $exclude \
						| cpio -ocvB \
						> /dev/rfp021

# the code below creates a timestamp file if the dump is an epoch dump

if [ $0 = edump ]
then
	touch $ddroot/epoch.$1
fi

echo "$0	$1	`date`" >> $ddroot/dumplog
ls -l $ddroot/dumplog
-- 
Gary S. Trujillo			      {linus,bbn,m2c}!spdcc!gnosys!gst
Somerville, Massachusetts		     {icus,ima,stech,wjh12}!gnosys!gst