I tried to install, and the process ran out of free disk space and failed. I’m restoring from a backup now, yay. How much space is required so I don’t end up in this situation the next time I try to upgrade?
The kb says 12.5 but I've always founds Apple estimates low on both space and RAM needed to run the system. You need to be able to work on it too.
Although Apple suggests 15 GB of free space, I've always found their estimates to be too low. Same goes for RAM. Even if it can install on that little free space, you still need space to be able to work effectively on it and run programs. A good rule of thumb is at least 10% free space. The more free space the better your system will run.
I'm glad to hear it all worked out for you.
I think the technical requirement for available storage was around 15GB or something like that. Good thing you had a backup :)
I failed on 36gb and had a success on 67gb - so a guess would be somewhere in between is the sweet spot.
so total newb question - I'm in the same situation so will my failed attempt to upgrade to Catalina have removed my previous Mavericks OS? Or can I go straight to respore from backup without dowloading a new copy of Mavericks?
@jbacus - happy to know I’ve got another 11 hours to run on the restore from fresh backup (which, thanks to your response, I now know will fail) before trusting to all that is sacred and wiping my HD.
I use Apple precisely because it all works so seamlessly (up until now) and I’ll continue to use Apple but this also has shaken my faith somewhat.
I know I’m an idiot for upgrading my oldest Maxbook first but I was so childishly delighted by the fact that Apple would still support an eight year old piece of hardware that I couldn’t help myself and I was doing it before common sense caught up with me. This has taught me a valuable lesson - “do not be first into the breech grasshopper”.
I shall as you suggest cull some bigger apps as well as dump those I’ve always kept just in case aiming for at least 150gb
thanks for updating.
The more free space available the better macOS is able to operate.
Same issue with me, my system stuck is reboot cycle .. also I made 15gb available before installation however it was not enough for it .. just now I restored my system from backup .
I had a rough day yesterday. I had 15gb free space when I started the Catalina update, but it failed with an 'out of space' error. The system was left in an un-bootable state. I had completed a fresh Time Machine backup just before starting the upgrade to Catalina, and so I tried to recover from that. That process also failed, with an error that I didn't understand- something very general sounding.
Eventually, I had to wipe my disk and reinstall macOS from the network. Oddly, this gave me a Mojave install, though it preserved my user account from somewhere. Probably iCloud, but that wasn't clear to me from the UI. From there, I deleted several large apps (Final Cut, Logic and Xcode) which freed up lots more disk space. I think I had something like 150gb free on my main system disk. I started the Catalina install again, and this time it took.
I'm so used to Apple's system upgrades going flawlessly, I guess I expected better this time through. Seems like a check of available space could have been done. I understand that sometimes it can be hard to precisely predict how much space will be required, but it would have been fine with me if Apple's engineering team took a very conservative approach to that estimating.
This is still my favorite operating system, but I think we need to work on our relationship a little bit. I'm kind of rattled by this experience.
If the download is 8GB then I'd allow at least 25GB for the install, the more the better.
How much free disk space is required to install Catalina?
