Preserving systems (was: recovering FC3 from a bad superblock)

[Benjamin Scott]

On May 18 at 11:59pm, Greg Rundlett wrote:
> It is truly amazing how much time and effort goes into installing and
> customizing/personalizing a system.

   Indeed.

> Back at Virtual Access Networks, we created a product that managed and 
> migrated computer 'personalities' for Windows.  ... I wish something like 
> that existed for Linux.

   A lot of that is "already done".

   I've been carrying the same $HOME/ directory around with me through several 
major system upgrades, a handful of hard disks, and more distributions then I 
can count.  All those dot files keep working.  The best software is 
backwards-and-forwards compatible, so that I don't have to care what version 
I'm running.  More software is merely good, and will migrate older files to 
newer formats.  For things that don't upgrade well, I can just "mv ~/.foo 
~/.foo.old" and start from scratch.

   You can do the same with /etc/, although that tends to make things messy as 
the distribution changes major subsystems around.  But there's always 
Slackware if you don't like that.  ;-)

   As far as all the custom software on a system, there are a couple things one 
can do.

   One is to keep a list of "after market" software installed via package 
manager.  You can then just re-install the extras after you re-install the 
base OS.  If you haven't been keeping such a list, and you're running Red Hat 
or Fedora, you can use

 	rpm -qa --qf '%{name}\t%{packager}\n' | fgrep -v redhat.com

to make one.

   For software outside of package management (i.e., built from source and 
installed via "make install" and the like), you have to put a bit more work 
into things, but it is still very doable.  Configure the software to live in a 
self-contained directory branch (like "/opt/foo") for starters, and carry your 
/opt/ tree around with you.  If you really want to ensure portability, build 
everything statically linked (note: that can lead to huge binaries).

   Hope this helps,

-- 
Ben <dragonhawk at iname.com>