Multiple Boot Option

[i-Scan]

My hobby has forced me to set up a system that runs Windows along with one of various Linux (different distributions.)
"Mirror, Mirror, on the waaa..." O M G ! - - Now I am starting to look like a geek. It dawned on me that I have not found any great single place to help deal with Multi-Boot issues. MX-15 is getting to be my most favorite and I'd like to think that left something here as insight to help someone else get through a predicament. It is an impossible task because there are simply way too many permutations to treat the problem as a gamut. So here follows a list of some things to learn about.

The best single guide I've found to date is this, The https://docs.fedoraproject.org/en-US/Fe ... index.html Fedora(tm) Multiboot Guide. It will help understand what's in store for their distribution and gain a good many insights.

"FIRST BE SURE YOU HAVE BACKED UP YOUR SYSTEM," says anyone who starts talking about installing ANY operating system. I so agree with that, sort of. I'm saying, "But, use something like the Macrium Reflect program to clone it all. Ordinary back-ups will contain all your data but you still may need to go back to find and re-install the programs you used to create and manage it all. Ordinary back-up does not save installed programs. <--- THE SLOW & INVOLVED METHOD. Cloning or Imaging your disk does. To clone you need duplicate media with the same or larger capacity and if you clone a 140Gb HDD onto a 250Gb HDD, you will have what seems to be two 140Gb HDDs. Both will be so identical that if you can boot from one you can boot from the other and not realize differences except drive letters or drive designations. Imaging is more like Ordinary back-up in that your data AND INSTALLED PROGRAMS are backed up into file/s that may then be reconstructed to the original system. All that said, best to just clone it, because the clone can be cloned back to the original booting from itself and cloning with the cloning software installed. <--- THE FAST & EASY METHOD/s.
Bottom line: When setting up a multi-boot system ALWAYS DUPLICATE YOUR DATA otherwise you will likely lose all your data and you can clone a clone. You can't boot off of your back-ups; you CAN run off of a clone!

I've realized the difficulties we face in setting up a working multiboot system are because there are too many variables. Most of these pertain the hardware of any single boot system. You don't much notice or need to notice until you need to keep your booting arrangements consistent with two or more operating systems.
To list some relevant variables...
Different Operating Systems (OS) and even different distributions of the same OS install differently.
Architecture? Is it on Apple, on Chrome Book, or, what is your Micro Processing Unit and Motherboard (MPU and MB)?
Basic Input Output System (BIOS) or Unified Extensible Firmware Interface (UEFI)?
UEFI Option? Is this a newer system with UEFI using the older methods? Maybe UEFI is an option.
Master Boot Record(MBR)/Globally Unique Identifier (GUID) Partition Table (GPT)?
GRand Unified Bootloader (GRUB)/Other Bootloader?
Removable or Installed Media?
CD Read only(CDR)/CD Write once read many (CD WORM)?
DVDr/DVDworm?
CD,DVD/Memory Stick USB Memory?

You might see with each choice you can make, less than half of the possible combinations remain. So be encouraged! You only have some number of the choices available because you don't likely have every factor to consider. If you do, you don't have time to to include them all. Then, if you get the help to include them all, you don't need to understand. LOL

So at least back up your data.
Then choose the new OS. (Maybe not so easy, even if you have specific software in mind.)
Then choose whether you may keep the old OS?
Consider your hardware? (Changing or adding hardware? You can find used Pentium or Core2 Duo systems without mouse, keyboard, or monitors for less than $100 on eBay or Amazon with free shipping. Many of these have Windows 7 installed. Some have a keyboard and mouse. Maybe you would prefer a second system? If you may require more than two OS options, there are eSATA or USB 3.0 to connect an external hard drive? Could you use Cloud systems or run OS on Virtual Box in RAM?) Is any of your bootable media larger than 2Tb capacity? Do you have only BIOS or UEFI and, if UEFI may you need to keep using it?
Can you boot from CD/DVD Live OS that does not remember what changes you've made? (Need more RAM?)
Can you boot from CDworm/DVDworm Live OS with persistence, that remembers some changes you'll make?
Can you boot from USB Live OS without (or with persistence? (USB Memory wears out at some point so get two.)

If you can do with one system you always use plus one of many others, my solution deals with that scenario very well. It would likely work with more one extra at a time. But, I'd say that you should back up every one of the extra OS just as you do with your permanently installed OS.

[richb]

Another option if you have the room and extra ports on your motherboard is to just drop in another HD or SSD, and install a new system to that new drive. Then during startup choose that drive. A function key will bring up a menu during startup to choose the boot drive, in my case F12. That way the OS's are completely segregated.

Another option is replaceable drives via a drive caddy. And there is always a virtual machine. With the powerful CPU's and large memory available on modern computers, VM's run as perceivably fast as native HD installs.