[WBEL-users] Upgrading from Whitebox to RHEL

[Mike B.]

At 4/26/2007 01:09 PM, Scott Silva wrote:

>wasting your money. They will probably recommend a clean install and careful
>data restore.

This raises a different question...one that may be obvious to 
long-time unix/linux folks, but not to us relatively new ones:

What is the best way to deal with upgrades and re-installations of 
linux?  That is, how do you preserve all the configuration changes, 
startup customizations, user accounts, cron scripts, DNS zone files, 
and other system management "stuff" that accumulates on a system over 
time when you re-install the OS or upgrade or switch to a different 
distribution?  Manually re-customizing and repeating all the setup 
work may be possible, but it's not an attractive option at all.

When you upgrade within a distro this is usually not an issue...files 
don't get deleted, upgrade scripts usually rename them if they get 
replaced with upgraded ones so you can merge in whatever is still 
relevant, and user directories aren't touched, etc..  When you do a 
clean install, this isn't the case.

Getting listings of files changed since you installed before you shut 
down the old system might be one way to catch what you need to save, 
but it will also catch a lot of stuff you may not care about (old 
logs, backup copies of edited files, programs that are going to be 
replaced anyway, programs you don't want anymore, etc.) and weeding 
it isn't much more attractive than repeating all the work.

If you were really organized, you'd maintain a copy of all updated 
critical files in some directory that isn't part of the 
"system"...like the sysadmin's home directory tree, or a directory 
off of /home or something, and always change there then copy into 
/etc, /var or wherever the files need to live, but all it would take 
is a small lapse of attention and you'd be missing something 
potentially important.  If you had such a thing, you could pretty 
easily copy again after making sure the file contents were still relevant.

How do the experienced folks deal with this problem?

-- Mike B.
-- 
I have not seen as far as others because giants were standing on my shoulders.