Big Sur Recovery Re-Installation Taking 33 Hours?

[IRONcast]

Hi All, got a MBP Early 2015 - decided to erase the Mac Partition and "Reinstall Big Sur" which started on 33 hours, dropped to 32, and now it's on 36h55m.

It is obviously pulling a 12.x GB image off the net. I have a 15mbps line.

Do I just wait this out? what is the tolerance if my internet goes off for a short while during this process?
13GB on a 10mbps line = 4 hrs download time theoretically.

I don't have other Mac devices, I am currently trying Shift + Option + ⌘ + R which has booted into Internet Recovery Mode, and hopefully it will install the original or close to Sierra, which is a much smaller image and I can then update from within the OS. However, even Intenet Recovery is taking 15+ minutes to start. How frustrating.

 

[HDFan]

Certainly sounds as if it is stalled. Assuming the disk erase/partition worked with no problems some possibilities:

1. Start over when the remaining time starts to consistently increase or remains stable after some hours. If you have a way to monitor network traffic see if the download is happening. If no traffic then the install is clearly stalled.
2. Run first aid after the reformat to verify the disk is ok
2. Move to a location, such as an Apple Store, where there is faster internet

 

[IRONcast]

Thanks HDFan, update: I restarted into Internet Recovery Mode, which took +-15 minutes to start, thereafter, I was able to Erase and create a new partition, and Yosemite is now Downloading additional components, which initially failed, but is now running after a second attempt - ETA is jumping between 15 and 21 hours. This is still madness, but seems more doable. I will just leave it now. In an ideal world this will eventually get done and once I'm in the OS I will update to Big Sur, which is painless and predictable. Unlike this.

 

[T'hain Esh Kelch]

I just reinstalled Montery on a 2016 Macbook with Internet recovery, so a slower machine than yours. After 3 hours, it said about 11 hours left, and then I went to bed. It was done when I got up 8 hours later though.

 

[IRONcast]

Thanks HDFan, update: I restarted into Internet Recovery Mode, which took 20+ minutes to start, thereafter, I was able to Erase and create a new partition, and Yosemite is now Downloading additional components, which initially failed, but is now running - ETA is 15 Hours. This seems more doable. I will just leave it now. In an ideal world this will eventually get done and once I'm in the OS I will update to Big Sur.

I just reinstalled Montery on a 2016 Macbook with Internet recovery, so a slower machine than yours. After 3 hours, it said about 11 hours left, and then I went to bed. It was done when I got up 8 hours later though.

Thanks, I am observing the ETA jumps - a lot. I am going to just leave this because honestly: Attempting to download DMG files online is a hassle and thus far is proving more frustrating. Though, an important lesson.

 

[IRONcast]

Update: this has dropped to 10 hours. Hmm, let's see what happens. It will be one of those "I'm just happy to see MacOS again, kinda scenarios.

 

[IRONcast]

Update (hopefully the last one before this works) - it has dropped to 3hrs 10m. Things are looking better. I.e. had this been the later OS, I would likely be sitting on many more hours+ still, due to much larger download size. So, the mentality is: once in OS, update to later MacOS. Once I am at least in the OS, I can continue to upgrade.

 

[David Hassholehoff]

When you are in a working state again, pull Big Sur down first and make a bootable installer on a USB drive.

This is easily done by opening the terminal and using the program softwareupdate, here is how it is used:

$USER on Mac-mini in ~
at 22:38:39 🢂  softwareupdate --list-full-installers
Finding available software
Software Update found the following full installers:
* Title: macOS Monterey, Version: 12.4, Size: 11819688KiB, Build: 21F79
* Title: macOS Monterey, Version: 12.3.1, Size: 11938730KiB, Build: 21E258
* Title: macOS Big Sur, Version: 11.6.7, Size: 12121823KiB, Build: 20G630
* Title: macOS Big Sur, Version: 11.6.6, Size: 12121263KiB, Build: 20G624
* Title: macOS Big Sur, Version: 11.6.5, Size: 12121404KiB, Build: 20G527
* Title: macOS Big Sur, Version: 11.6.4, Size: 12147782KiB, Build: 20G417
* Title: macOS Big Sur, Version: 11.6.3, Size: 12143674KiB, Build: 20G415
* Title: macOS Big Sur, Version: 11.6.2, Size: 12141944KiB, Build: 20G314
* Title: macOS Big Sur, Version: 11.6.1, Size: 12137180KiB, Build: 20G224
* Title: macOS Big Sur, Version: 11.5.2, Size: 12149332KiB, Build: 20G95

$USER on Mac-mini in ~
at 22:40:18 🢂  softwareupdate --fetch-full-installer --full-installer-version 11.6.7

Once you have Big Sur, create the install media with this command: sudo /Applications/Install\ macOS\ Big\ Sur.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume where MyVolume is the name of the USB volume.

 

[IRONcast]

When you are in a working state again, pull Big Sur down first and make a bootable installer on a USB drive.

This is easily done by opening the terminal and using the program softwareupdate, here is how it is used:

$USER on Mac-mini in ~
at 22:38:39 🢂  softwareupdate --list-full-installers
Finding available software
Software Update found the following full installers:
* Title: macOS Monterey, Version: 12.4, Size: 11819688KiB, Build: 21F79
* Title: macOS Monterey, Version: 12.3.1, Size: 11938730KiB, Build: 21E258
* Title: macOS Big Sur, Version: 11.6.7, Size: 12121823KiB, Build: 20G630
* Title: macOS Big Sur, Version: 11.6.6, Size: 12121263KiB, Build: 20G624
* Title: macOS Big Sur, Version: 11.6.5, Size: 12121404KiB, Build: 20G527
* Title: macOS Big Sur, Version: 11.6.4, Size: 12147782KiB, Build: 20G417
* Title: macOS Big Sur, Version: 11.6.3, Size: 12143674KiB, Build: 20G415
* Title: macOS Big Sur, Version: 11.6.2, Size: 12141944KiB, Build: 20G314
* Title: macOS Big Sur, Version: 11.6.1, Size: 12137180KiB, Build: 20G224
* Title: macOS Big Sur, Version: 11.5.2, Size: 12149332KiB, Build: 20G95

$USER on Mac-mini in ~
at 22:40:18 🢂  softwareupdate --fetch-full-installer --full-installer-version 11.6.7

Once you have Big Sur, create the install media with this command: sudo /Applications/Install\ macOS\ Big\ Sur.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume where MyVolume is the name of the USB volume.

100% - this is great advice - I won with the install, which finished in around 5 hours, booted into Yosemite, upgraded to Big Sur and again, into Monterey (this morning, I was bored and needed to see how it runs) - turns out, it's a jittery waste and as we type I'm making a Big Sur (my new fav. OS) - bootable USB using your instructions above, AND another one in-case something goes borked with the first one.

I will end up with a box of Mac bootable USBs lol.
Thanks team, winning!!!