[CentOS] newbie question on installation over existing Linux

[Robert Heller]

At Sun, 07 Jun 2015 15:16:45 -0700 CentOS mailing list <centos at centos.org> wrote:

> 
> If I choose to do a fresh install of CentOS 6 with "replace existing
> Linux systems", will it also wipe out my /home directory? In the past
> when I've done this with another Linux distro, /home was not affected.

Probably...

> 
> Or, would I need to do "fresh" install and then muck with partitioning
> using a Custom Layout? Right now, it's kind of looking like the latter
> to me, and if so, will I lose data?

It is not hard to do the custom layout. Just select the 'system' filesystems
(eg /, /usr, /var, /boot, and the like) and select 'reformat as whatever (ext4
usually), and set the mount points to what they were. Then select the /home
(and any other 'user data' type file systems) partition(s) and select 'use as
is' and give the proper mount point(s).  If you take your time and are 
careful, you won't lose any data, but do go ahead and do careful backups 
anyway.  You *might* want to note down any special configuration information 
you need to preserve (eg static IP address, a list of custom software you want 
to have installed, and so on).

Basically the 'Custom Layout' is for two general cases:

1) you have an unformatted disk and you want to do something non-default with 
the partitioning.

2) you want to re-install and retain some non-system data partitions.

There is a third possibility where you want to have a multiple Linux boot
system (this usually means using /boot 'as is' for the second+ install, often
with the installer bitching about doing that, and it usually means having way
too much fun fiddling with grub.conf later), although mostly these days, you
just pick one Linux distro for your 'host' and run one (or more) 'other'
linuxes as VMs.

> 
> I spent some time on the Forums and reading the RH documentation, but,
> no real answers to this specific question.
> 
> Thanks for any help.

-- 
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