so just /Applications/Install macOS Catalina.app/Contents/Resources/startosinstall --agreetolicense in Files and Processes or do I need to make this a script?

@talkingmoose I checked the policy log for one of the devices and this is what I'm getting now: [STEP 1 of 4]
Executing Policy macOS Catalina Upgrade
[STEP 2 of 4]
[STEP 3 of 4]
Running command /Applications/Install macOS Catalina.app/Contents/Resources/startosinstall --agreetolicense...
Result of command:
Error: Prepare recovery failed with error: Error Domain=com.apple.OSInstallerSetup.error Code=303 "Installation of macOS could not continue." UserInfo={NSLocalizedDescription=Installation of macOS could not continue., NSLocalizedRecoverySuggestion=Installation requires downloading important content. That content can't be downloaded at this time. Try again later.}
Fetching OS Recovery info from server...
[STEP 4 of 4]

Haven't read through the entire thread, but I don't see anyone appending && reboot to the end of their command.

Also any chance the options have changed a bit compared to the above posts (--pidtosignal, --forcequitapps, etc.). ?

$ /Applications/Install macOS Catalina.app/Contents/Resources/startosinstall --usage
Usage: startosinstall --volume <target volume path>

Arguments
--license, prints the user license agreement only.
--agreetolicense, agree to the license you printed with --license.
--rebootdelay, how long to delay the reboot at the end of preparing. This delay is in seconds and has a maximum of 300 (5 minutes).
--pidtosignal, Specify a PID to which to send SIGUSR1 upon completion of the prepare phase. To bypass "rebootdelay" send SIGUSR1 back to startosinstall.
--installpackage, the path of a package (built with productbuild(1)) to install after the OS installation is complete; this option can be specified multiple times.
--eraseinstall, (Requires APFS) Erase all volumes and install to a new one. Optionally specify the name of the new volume with --newvolumename.
--newvolumename, the name of the volume to be created with --eraseinstall.
--preservecontainer, preserves other volumes in your APFS container when using --eraseinstall.
--forcequitapps, on restart applications are forcefully quit. This is the default if no users are logged in.
--usage, prints this message.
--volume, path to the target volume.

Example: startosinstall --volume /Volumes/Target
$

I haven't tested this in Catalina yet, seems like an Apple scream test right now..

¯_(ツ)_/¯

This is what we've used with Mojave and High Sierra if it matters:

/Applications/Install macOS Mojave.app/Contents/Resources/startosinstall --agreetolicense --nointeraction && reboot

@mmark, as part of any upgrade the installer will need to connect to the internet to download firmware onto the Mac. Sounds like your Mac may not be connected to your network or Apple's network had a temporary issue.

If you have a mobile hotspot, that's worth testing as part of your network troubleshooting.

Its working now, it just takes forever to download all necessary files.

@donmontalvo Does your reboot append work on File Vaulted machines?

@Hugonaut Morning, great little script, but what is the process to add it back to Casper at the same time. I remember that you were able to run a package along with erasing or upgrading. Is that still true, do you know? and if so what would that command line be.

Have a great day my friend!

I'm having issues using https://github.com/kc9wwh/macOSUpgrade script.
It worked fine when upgrading from 10.11 to 10.13.

When trying to upgrade from 10.13 to 10.14 keep getting "We were unable to prepare your computer for macOS Mojave. Please contact the IT Support Center."
It pulls the Mojave installer down but after that it fails .

2020-03-03 12:08:13+00 UKM2315 install_monitor[12420]: Temporarily excluding: /Applications, /Library, /System, /bin, /private, /sbin, /usr
2020-03-03 12:08:13+00 UKM2315 install_monitor[12420]: PackageKit: Locking applications
2020-03-03 12:08:13+00 UKM2315 installd[1055]: PackageKit: Writing receipt for installmacosmojave to /
2020-03-03 12:08:13+00 UKM2315 installd[1055]: PackageKit: Touched bundle /Applications/Install macOS Mojave.app
2020-03-03 12:08:13+00 UKM2315 installd[1055]: Installed "Install macOS Mojave" ()
2020-03-03 12:08:13+00 UKM2315 install_monitor[12420]: Re-included: /Applications, /Library, /System, /bin, /private, /sbin, /usr
2020-03-03 12:08:13+00 UKM2315 installd[1055]: PackageKit: releasing backupd
2020-03-03 12:08:13+00 UKM2315 installd[1055]: PackageKit: allow user idle system sleep
2020-03-03 12:08:13+00 UKM2315 installd[1055]: PackageKit: ----- End install -----
2020-03-03 12:08:13+00 UKM2315 installd[1055]: PackageKit: 16.0s elapsed install time
2020-03-03 12:08:13+00 UKM2315 installd[1055]: PackageKit: Running idle tasks
2020-03-03 12:08:13+00 UKM2315 installd[1055]: PackageKit: Done with sandbox removals
2020-03-03 12:08:13+00 UKM2315 installer[12419]: PackageKit: Registered bundle file:///Applications/Install%20macOS%20Mojave.app/ for uid 0
2020-03-03 12:08:13+00 UKM2315 installd[1055]: PackageKit: Removing client PKInstallDaemonClient pid=12419, uid=0 (/usr/sbin/installer)
2020-03-03 12:08:14+00 UKM2315 installer[12419]: Running install actions
2020-03-03 12:08:14+00 UKM2315 installer[12419]: Removing temporary directory "/var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/T//Install.12419mTTq1C"
2020-03-03 12:08:14+00 UKM2315 installer[12419]: Finalize disk "UKM2315"
2020-03-03 12:08:14+00 UKM2315 installer[12419]: Notifying system of updated components
2020-03-03 12:08:14+00 UKM2315 installer[12419]: 2020-03-03 12:08:14+00 UKM2315 installer[12419]: * Summary Information *
2020-03-03 12:08:14+00 UKM2315 installer[12419]: Operation Elapsed time
2020-03-03 12:08:14+00 UKM2315 installer[12419]: -----------------------------
2020-03-03 12:08:14+00 UKM2315 installer[12419]: disk 0.02 seconds
2020-03-03 12:08:14+00 UKM2315 installer[12419]: script 0.00 seconds
2020-03-03 12:08:14+00 UKM2315 installer[12419]: zero 0.00 seconds
2020-03-03 12:08:14+00 UKM2315 installer[12419]: install 16.83 seconds
2020-03-03 12:08:14+00 UKM2315 installer[12419]: -total- 16.86 seconds
2020-03-03 12:08:14+00 UKM2315 installer[12419]: