How To Format An iMac To Install Ubuntu

[EDLIU]

How do I format my old iMac so I can install and run (only) Ubuntu?

Thanks.

 

[leo-tech]

> How do I format my iMac so I can install Ubuntu?

Your question contains false premise ("in order to install Ubuntu, I need to format my iMac")

One of the options: keep your current macOS, install VirtualBox, install Ubuntu in VM, run both OS's simultaneously.

 

[deconstruct60]

Anyone that can help me with the question?

Thanks.

Two seconds of asking Google turned up ....

https://www.lifewire.com/dual-boot-linux-and-mac-os-4125733

also

Create a bootable USB stick on macOS | Ubuntu

Ubuntu is an open source software operating system that runs from the desktop, to the cloud, to all your internet connected things.

tutorials.ubuntu.com

It isn't the iMac that needs formatting it is the storage drive. If your iMac has a Fusion Drive step zero would be to get another drive to install onto. ( There are some incantations to get Window/Linux onto a Fusion drive but if 'lost' on what the install process is then probably also don't want that kind of complexity).
If you are talking about completely wiping the entire iMac internal drive of all macOS partitions then probably should at least experiment with dual boot first to see what works and what doesn't. The steps in the linked list above are shorter if just looking to erase the whole storage device and start from a clean slate. ( presuming there is no system with a T2 involved here. Current mainstream iMacs don't but longer term that is an additional issue. At least some small macOS presence is pragmatically needed on those systems. Similar issue though in non T2 systems, Apple bundles firmware upgrades with macOS upgrades. Pragmatically will need some attached macOS instance to run the bundled upgrades against to pick up firmware upgrades. That can be an external drive though. ).


If looking to erase the whole drive the easiest way to do it is to boot into Recovery Mode ( How to reinstall macOS from macOS Recovery . if follow first "half" of steps of erasing the drive. macOS Recovery has an Internet recovery option (if have a much older iMac the incantation to start it is different. Can follow "macOS Recovery" link in this article for more info. ). Wiping out the whole drive isn't that hard. A live boot Linux instance can probably do it also with general disk tools for a non T2 system. Sharing space on a single storage drive is where need more selective tools.


reFind works just with Linux also. ( the directions above are aligned with installing reFind on a system with macOS 'first' via the macOS specific installer. )

 

[EDLIU]

Scheme: GUID Partition Map? Master Boot Record?

Format: Mac OS Extended (Journaled)? FAT? ExFAT?

Thanks.

 

[revmacian]

Scheme: GUID Partition Map? Master Boot Record?

Format: Mac OS Extended (Journaled)? FAT? ExFAT?

Thanks.

Most Linux distros, including Ubuntu, take care of the formatting during installation. I ran various Linux distros for almost 20 years and they all took care of the drive formatting during set up.

 

[EDLIU]

Most Linux distros, including Ubuntu, take care of the formatting during installation.

I want to Zero Out my old iMac HDD. Can I choose GUID Partition Map and Mac OS Extended (Journaled)?

Thanks.

 

[revmacian]

I want to Zero Out my old iMac HDD. Can I choose GUID Partition Map and Mac OS Extended (Journaled)?

Thanks.

You can, sure, but Ubuntu will wipe the hard drive and format the file system it needs anyway. When I installed Ubuntu these are the steps I usually took:
1. Buy a new computer (doesn’t matter which OS it runs because it will be removed)
2. Insert Linux install media (CDROM or USB thumb drive)
3. Run the Linux installer and let it do its thing
4. Reboot the system and it’s ready to go
No need to mess about with the hard drive because Linux is going to re-partition and re-format anyway.

If you’re going to allow Ubuntu to take the entire hard drive then it doesn’t matter what you do before installing Ubuntu because Ubuntu will wipe and format anyway. This is pretty much standard operating procedure for most Linux and BSD distros. The only tricky part is if you want to divide the hard drive and keep the other OS, like Windows.

 

[EDLIU]

I have an old iMac (500GB HDD, 4GB Memory). How do I partition my disk to install and run (only) Ubuntu on it?

Another question, what are the differences between partitioning a disk as /, /home, and /boot, /home, /usr?

Should I partition my iMac as /, /home, or /boot, /home?

How do I crate a "swapfile"(in Ubuntu 19.10)?

According to my iMac's spec, how do I set the disk space for each partition(e.g. 25GB for /, 475GB for /home)?

Thanks.

 

[Ledgem]

It's been many years since I tried any Linux distributions, and I don't recall any of them asking for those specifics. The operating systems all handle their own swap file. The directories you mention are all created by the operating system, so you shouldn't need to do any of that.

You might have more success (and likely quicker replies) if you went to an Ubuntu forum and asked the questions there. The vast majority of users here run macOS rather than Ubuntu or another Linux distribution, so there's just not much familiarity with it.

If you're using a guide to install Ubuntu, share it here and let us know which step you're stuck on - we might be able to help clarify some things. Barring that, I'm willing to go through the Ubuntu install process on a virtual machine to help guide you if you're really stuck, but an Ubuntu or general Linux forum should be able to resolve these questions for you.