What format type to use when making a bootable Big Sur SSD drive?
What format type to use when making a bootable Big Sur SSD external drive? Is it APFS with GUID?
iMac 27″ 5K, macOS 10.15
Use APFS, not APFS (case-sensitive). With GUID.
6 replies
Do you want to install the OS on the external SSD or do you want to create a bootable installer on the SSD? Those are two different things.
If you want to install Big Sur onto the SSD, and you want to use a bootable installer, then you would need to create the bootable installer on a different drive, a 16GB USB stick would be the simplest choice.
You cannot create the bootable installer on the SSD, then use that to install the OS on the SSD.
I want to create an external SSD that I use to boot my iMac 2017 so I no longer use the internal HD. As you mentioned I would need a 16 GB USB flash drive. Then I boot off this and specify the SDD. Follow instructions at https://support.apple.com/en-us/HT201372 .
If you are trying to make a bootable installer, then you have already downloaded the Big Sur installer. Why not just run that and specify the SSD as the destination?
You might want to make the bootable installer just to have a copy. Or copy the installer to another drive. When you run the installer, it will normally delete itself, but I don't know if that applies to when you install on another drive.
how long does it take for the installer flash to be created?
I haven't made one for Big Sur, but others have taken about 10 minutes.
Must I use a very fast speed Flash?
No.
How long for the installer to load Big Sur on the SSD?
I have never timed it. Seems to be about 45 minutes to an hour, but I usually just start it and go to sleep.
If you use a bootable installer, it should be at the low end of that range as everything has already been downloaded.
When you upgrade from Software Update, it has to download the install files while it is upgrading.
I want to create an external SSD that I use to boot my iMac 2017 so I no longer use the internal HD. As you mentioned I would need a 16 GB USB flash drive. Then I boot off this and specify the SDD. Follow instructions at https://support.apple.com/en-us/HT201372 .
How long does it take for the installer flash to be created? Must I use a very fast speed Flash? I have some older USB flash drives. How long for the installer to load Big Sur on the SSD?
Thanks for your help.
The suggestion to initiate the install from the iMac’s HD worked well. Now I need to create the users on the external SSD and move their data over from the HD. I want to do a clean install and move only their documents, photo library (not on iCloud), music files, and reinstall the apps not from the App Store. Mail, Notes will come from the iCloud. I exported the bookmarks from The browsers and will import them back. What is the easiest way to do the transfer of the files from an user account on the HD to its corresponding account on the SSD?
Log in as the new user and add that user to the old user's home folder (in /Users) using Get Info. You will have to Authenticate to add your new user to the old. You only need Read permissions.
Once done, you can drag the files from old user's home into the new user's home folder.
I don't know what issues might have moving the entire music folder over, so I would suggest just importing into the new user Music app from the old user's music folder. Unless you've done a lot of tagging and such, it should not be an issue.
If you did, then move the music media folder over along with the Music Library. I'm not sure how that will work out, though. You may have to go back to the manual import and re-tag everything.
You should be able to just copy the Photos.photoslibrary over, double-click on it to open, then in Photos Preferences, set it as the System Photos Library.
What format type to use when making a bootable Big Sur SSD drive?