Adding Debian 9.9 to existing RHEL 8.0 system
 

I have a system with RHEL 8.0. I need to install Debian 9.9 and make the system dual-bootable. Would be grateful for any insight on how to do this especially if it includes specific steps. A second disk will be added for the Debian installation.

(I was hoping that I could somehow add Debian without blowing away RHEL)

In addition, I am a new Linux user.

Thank you--Nina

Hello beachmouse Nina (sic).
dual booting is a fairly common thing; I'm sure you can find suitable instructions easily. maybe here:
https://www.startpage.com/do/dsearch...el+with+debian

Thank you; I had checked many of the items in the link that you sent before posting here, but many of them dealt with Windows/Linux dual boot situations. The ones that discussed 2 Linux distros didn't have enough specifics to be helpful to a new user.

disconnect your rhel drive install Debian to the additional drive, reconnect rhel drive

I personally would recommend using only a single grub instance to control both OS's. Follow colorpurple21859's advice then use the grub on whatever install you wish, and add the other OS to that grub. I don' think you "have" to do this but you may get 2 grub prompts if you don't. I have never dual booted 2 linux installs so not sure the outcome of having 2 grub installs.

Colorpurple21859, Sevendogsbsd--thank you so much. I will try these this weekend and hopefully all will go well...

The disk/ bootloader that is first in bios boot order will be the controlling bootloader

I haven't dual booted in years and never dual booted Linux; forgot about the BIOS boot order.

I usually duel boot 2 or 3 distros along with windows on my home systems

The only windows install I own is on this laptop and is used solely for digitally signing PDFs for work, and for posting here because my main PC is off while I am working :) I run some Linux variants but only in VMs.

Used to dual boot with windows 10 for gaming but game up on windows 10 entirely (caveat above) for gaming.