On 12/28/25 07:10, Richard Owlett wrote:
I've been a computer _user_ since early 60's [undergrad E.E. student].
I have used multi-boot since the days of Squeeze.
I wish to grok multi-boot.
I currently default to Debian 12 , other options are available.
After doing some years overdue disk housekeeping, I wish to *ADD* a
clean install of Trixie.
Some of the housekeeping will be for re-purposing some existing disk
partitions.
To safely do that, I need to know the details of the power on boot
sequence and what files are used.
I'm carefully not asking specific questions as decades of tech support
(in another field) has taught me that "wrong questions" can cause as
much grief as "wrong answers" ;{
TIA
For closed-source x86/x86-64/amd64 computers, I advise against
multi-boot. Even when I was able to get it working, any change to
anything boot related by any OS was likely to break the ability to boot
other and/or all OS's on the same disk. As for operations, I needed a
common data store; either a direct-attached disk with a
lowest-common-denominator filesystem, or a network disk. This added
complexity, reduced performance, and risked data corruption. And, no
matter which OS I was running, I always needed to run something on
another OS. Multi-boot was unreliable and maddening.
My solution for the past ~25 years has been to pick one drive form
factor and interface (currently 2.5" SATA), install drive racks in my
computers, buy additional disks, and put one OS on each disk:
https://www.startech.com/en-us/hdd/mobile-racks
This allows me to mix and match OS's and computers as desired. The
flexibility is very useful for system administration chores, including
partition reorganization and data migration.
When I want multiple OS's all running at the same time on the same
computer, I install a hypervisor (VirtualBox) and create virtual
machines. A good hypervisor will allow filesystem and/or hardware
access from VM's to host disks.
David
