Re: Debian 8 and Debian 9 Dual Boot
On 11/13/2017 01:10 AM, David Christensen wrote:
On 11/12/17 19:27, Dan Norton wrote:
My first Linux install was about one year ago. After some missteps, I
have used Debian 8 in reasonable satisfaction on the desktop during
that year. Now I want to leave 8 in place and do a network install
for Debian 9 on the same disk and switch back and forth at boot time.
I think your best bet is to migrate from Debian 8 to Debian 9:
1. Image, backup, and/or archive everything. You will especially
want to get a copy of the /etc tree onto a USB flash drive so you can
see LVM, fstab, etc., configuration settings for mounting the Debian 8
disk under Debian 9.
Please say more about the configuration settings. I back up /home and
/var. The git stuff is in /opt and pushed to GitHub. Should the /etc
tree be backed up also? How would the settings be used from 9?
Sobering advice - good! Makes me re-think some things. A bit inefficient
WRT disk space.
2. Put your bulk data onto a separate drive or a file server/ NAS.
3. If your computer has a spare drive bay, buy a new drive, unplug
your old drive, install the new drive, install Debian 9 onto the new
drive, reconnect the old drive and mount read-only under Debian 9, and
migrate your settings and remaining data from the old drive to the new
drive. Your BIOS/UEFI should allow you to boot from either drive
during this process. So long as you don't damage the Debian 8 disk,
you can always fall back to Debian 8 if the migration goes badly.
4. If you computer does not have a spare drive bay, buy a new drive
and a USB external drive enclosure, put your old drive in the
enclosure, install the new drive, install Debian 9 onto the new drive,
plug in the old drive and mount read-only under Debian 9, and migrate
your settings and remaining data from the old drive to the new drive.
Again, your BIOS/UEFI should allow you to boot from either drive and
you can fall back to Debian 8 if necessary.
You did say "migrate" and not "upgrade" as I first read. Thanks David.