Two versions same drive

I’m sure I got a reply to this question some time ago, but I can’t find it with “search”. How do I install two different versions of Leap or Tumbleweed on the same drive?
Thanks in advance.

I assume you have one OS on one or more partitions on that disk and enough free space for the partitions for the new to be installed OS.

Then just start the installer. It will probably out of itself suggest to create new partitions in the free space (there is somewhere a question like: should I install over the old OS, of course you say NO to that). All as normal.

Just like with Windows and Linux sharing a legacy/BIOS boot PC installation, on UEFI/GPT installations sharing one ESP, each’s installer and Grub updater will usurp boot control from the other(s). It’s important with multiple same-name distros on a UEFI/GPT installation quickly after installation completes to append a (quoted) unique string in /etc/defaut/grub’s GRUB_DISTRIBUTOR= if you wish to exercise control over which Grub you’ll see when you power up. This results in a unique name for each for its boot directory on the ESP filesystem: e.g.

# ls -1
debian11
debian12
opensuse153
opensuse154
tumbleweedkde
tumbleweedxfce
ubuntu20
ubuntu22

There’s a fallow bug from 4 years ago to set this up during openSUSE installation.

Always rename the boot loader entry from opensuse to something more meaningful. Otherwise you will inadvertently overwrite opensuse:
Host erlangen currently has:

**erlangen:~ #** efibootmgr  
BootCurrent: 0000 
Timeout: 1 seconds 
BootOrder: 0000,0001 
Boot0000* tumbleweed-nvme0n1p2 
Boot0001* tumbleweed-test 
**erlangen:~ #**