I was planning to upgrade the OS to BigSur, When I try to download the BigSur OSX App file from Self Service the size of the file is got reduced to 27.5MB. Whereas the actual file size is 12.26GB.
I tried to upgrade the OS with 27.5MB file. I was able to upgrade it to BigSur successfully without any error and it is working fine.
(Devices are managed by Jamf)
Is this the expected behaviour ?
Hi @syed28257. It sounds like you accidentally packaged the stub installer. There are two OS installer types - the stub, which contains only limited bits to download the full installer during upgrade, and the full installer. Make sure you're adding the full ~12 GB installer to Self Service and not the stub.
Jamf's Bill Smith has a great article detailing a few different ways to download and package the full installer as part of a larger reinstall workflow. https://www.jamf.com/blog/reinstall-a-clean-macos-with-one-button/ Look for the heading "Deploying the installer." I personally like the fetch-installer-pkg.py script option the best (https://github.com/scriptingosx/fetch-installer-pkg) as I can then take that package and upload it directly to my DP to make available in a policy. Hope that helps!