[CentOS] cents 5.6 ..... futur

[Les Mikesell]

On 4/16/11 12:18 AM, Devin Reade wrote:
> John R Pierce<pierce at hogranch.com>  wrote:
>
>> have all your configuration under a change management system, with an at
>> least semi-automated installation procedure, such as kickstart.
>
> Or have the self discipline to keep a text file (or other record) of
> *all* changes you make to a system as root or other role account.
> I always keep a running log, complete with dates and who makes the
> change, as /root/`hostname`-mods.  Trivial operations (that any junior
> sysadmin would be expected to know) get described. Anything more complex
> gets the actual commands entered (minus passwords).
>
> It's extra work, however not only has it saved my bacon a lot over the
> years in figuring out, after the fact, what caused something to break
> but even more often it has been invaluable in recreating a system or
> quickly implementing similar functions on other systems.
>
> Yes, this is a form of a change management system, just with little
> overhead.  It is also more suited to server environments where each
> one might be slightly different as opposed to (for example) corporate
> workstation environments where you can have a large number of homogeneous
> machines.  In that case, there are many other tools more suitable,
> with higher setup costs, but the amortized cost is lower.

This is all good advice, but you really should be able to figure things out if 
you know what services the old system was running and you have a backup of your 
old /etc directory.  At least for the rpm-packaged programs in the base and most 
3rd party repos, all of the configuration files will be under /etc, and most 
will have the part where you make local changes abstracted out into a file under 
/etc/sysconfig.  Having a better change management system would let you diff 
your current files against the original distribution copies to easily see the 
specific changes you made. This may be a little harder if there are big changes 
in the distribution versions but still not impossible to figure out.

If you have compiled anything yourself it probably installed under /usr/local 
and you are on your own at reproducing that, but if it is old enough to forget 
you probably want to see if RPM packaged versions are available now that would 
be easier to maintain.

-- 
   Les Mikesell
    lesmikesell at gmail.com