Path: utzoo!utgpu!news-server.csri.toronto.edu!clyde.concordia.ca!uunet!sci34hub!gary
From: gary@sci34hub.UUCP (Gary Heston)
Newsgroups: comp.unix.i386
Subject: Re: Interactive 2.2 install query
Keywords: Interactive 2.2 install problems?
Message-ID: <690@sci34hub.UUCP>
Date: 9 Jul 90 16:31:25 GMT
References: <1990Jul07.125218.24439@virtech.uucp> <1990Jul07.152106.23429@turnkey.tcc.com>
Reply-To: gary@sci34hub.sci.com (Gary Heston)
Organization: SCI Technology, Inc., Huntsville, Al.
Lines: 52

In article <1990Jul07.152106.23429@turnkey.tcc.com> jackv@turnkey.TCC.COM (Jack F. Vogel) writes:
>In article <1990Jul07.125218.24439@virtech.uucp> cpcahil@virtech.UUCP (Conor P. Cahill) writes:
>>like some of my crontab entries got blown away, my gettydefs file got blown
>>away,etc).  If you have room, make sure you have an on-line backup copy
>>of your root FS so that you have immediate access to whatever gets blown 
>>away.
 
>I have a WD1006 based system rather than ESDI, and also did the upgrade
>rather than reinstall. I also had no other problems than what Conor mentioned.
>Just remember to make backup copies of your crontab files, /etc/inittab, and
>so forth.   ....

In order to save space, and ease disaster recovery, you can create a 
skeleton image of the root fs directories, and link the configured 
files (inittab, crontabs, uucp device files, passwd, and so on) 
into it. Then, make a quick backup of this directory, do your update
(which will probably overwrite a few files, no matter which vendor 
you're dealing with), and restore the directory. Since the files will
still be linked, restoring the directory restores the configuration,
and saves lots of hair pulling. For example, I use a directory
named /x for this, so I have /x/etc, /x/bin, /x/usr/bin, /x/usr/lib,
and whatever subsidiary directories I need. Then:

ln /etc/passwd		/x/etc/passwd
ln /etc/inittab		/x/etc/inittab
ln /etc/gettydefs	/x/etc/gettydefs
  .....
  (whatever other files you configure...)

(This can be a cron-executed script to make sure things don't get
accidentally unlinked.) Now, if you tar -cvf /dev/rfd0 /x everything
gets saved. The tar can be done from within /x if you want to 
restore directly to the system files, by doing the tar -x from
/ instead of /x.

The only hangup is that this only works within a file structure,
obviously, so if you have /usr mountable you have to save those
files separately. 

I came up with this trick while testing successive beta releases,
to save myself a lot of re-config work. It's proven to work quite
well, and eliminates the need for a separate root fs image. It saves
backup time since you don't need to dump the whole root fs, just the
one directory. 

Comments? 

-- 
    Gary Heston     { uunet!sci34hub!gary  }    System Mismanager
   SCI Technology, Inc.  OEM Products Department  (i.e., computers)
"The esteemed gentleman says I called him a liar. That's true, and I
regret it." Retief, a character created by Keith Laumer.