I'd like to use a clean install of the latest Big Sur (11.4 or 11.5) on a machine that currently has Yosemite installed. I'd like to keep using Yosemite due to some legacy apps/licenses.
- Ideally I'd like to edit the same files from both Yosemite and Big Sur
- I've also considered accessing data and installing/running an app on a different partition to the one with the OS
- However, I'm realising that there could be challenges due to the HFS and APFS formatting
I have Yosemite (10.10.3) installed on the Macintosh HD partition. I have two other partitions which I use as data storage (e.g. Word, Excel files).
P1) Macintosh HD (480GB, Yosemite already installed)
P2) 2 - 430GB
P3) 5 - 90gb
Scenario (i):
P1) Macintosh HD (480GB, Yosemite already installed)
P2) 2 - 430GB (Big Sur would be installed)
P3) 5 - 90gb
Scenario (ii):
P1) Macintosh HD (480GB, Yosemite already installed)
P2) 2 - 430GB
P3) 5 - 90gb (Big Sur would be installed)
All three partitions according the disk util
are:
File System Personality: Journaled HFS+
Type (Bundle): hfs
Question that arises:
- With reference to the two scenarios above, is it possible to access (both read & write) files (e.g. a Word document) and or run apps stored on a different partition than the one with the running OS?...Or will the partition (with the other OS installed) no longer be visible?
A.) If yes, how does this work if one of the drives is JHFS+ and the other is APFS?
B.) If not, would it be better to store data on a partition that doesn't have any OS installed (used almost like an external SDD except that it's internal)?
C.) Would there be any issues from installing apps not on the same partition as the one with OS-installed? E.g. app files that need to be located in the system, caches, application support and library folders
Machine: MacBook Pro (Retina, 15-inch, Mid 2015) 1TB SSD (3 Partitions):
/dev/disk0
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *1.0 TB disk0
1: EFI EFI 209.7 MB disk0s1
2: Apple_HFS Macintosh HD 479.5 GB disk0s2
3: Apple_Boot Recovery HD 650.0 MB disk0s3
4: Apple_HFS 2 - 430GB 430.3 GB disk0s4
5: Apple_HFS 5 - 90gb 89.7 GB disk0s5
I've made an attempt to answer my question below but I'm still unclear on a few points (I've added my research with links there).
Install OS X Yosemite
application. This should be the latest version of Yosemite, which should be compatible with your Mac. You will need to use your existing Yosemite to create theInstall OS X Yosemite
application. You can use this link to create the bootable USB Yosemite installer. The command for Yosemite has been omitted. You will have to adapt the command for El Capitan.