Attempts to update macOS to 10.14.5 using startosinstall fail intermittently

Number:rdar://51006318 Date Originated:05/21/19
Status:Open Resolved:
Product:macOS - Install macOS Product Version:10.14.5
Classification:Bug Reproducible:Rarely
We have identified 11 devices that are having issues updating to macOS Mojave 10.14.5 using startosinstall and the latest Install macOS installer. 

The problem is intermittent and, in the support cases we've received, appears to be isolated to devices with the Apple T2 Security Chip. 

This problem manifests as devices proceeding with a macOS Mojave triggered by startosinstall, then booting to the Apple startup screen, macOS boots up to the same version of macOS it began with, not 10.14.5. 

After multiple attempts, we have seen some devices eventually succeed. 

Steps to Reproduce:
1) Execute the startosinstall belonging to 10.14.5 install macOS Mojave app:

sudo launchctl asuser <loggedInUserID> /tmp/AVEDMPXQOPDSJDIE/macosmojave-10.14.5.dmg/Contents/Resources/ --agreetolicense --rebootdelay=1 --applicationpath=/tmp/AVEDMPXQOPDSJDIE/macosmojave-10.14.5.dmg/Contents/Resources/ --pidtosignal=<agent_process_id>

2) Observe macOS reboot to the Apple startup screen

3) Authenticate  

4) Once at the user desktop, open About This Mac. Observe macOS version has not changed (updated) 

Expected Results:
macOS updates to 10.14.5 after progressing through the usual update screens. 

Actual Results:
macOS attempts an update to 10.14.5 that fails, resulting in no system update. 

Device that produced sysdiagnose: Mac OS X 10.14.4 (Build 18E226)


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