A brief update to https://managingosx.wordpress.com/2018/01/25/early-notes-on-deploying-images-to-imac-pro/ :
This is much easier now with 10.13.4, which has updated asr restore to handle some of the tasks needed when restoring an image to iMac Pro.
I still recommend using AutoDMG to generate a deployment image from a 10.13.4 Install macOS High Sierra.app (and optionally your own additional packages).
The one restore workflow I know works is this:
Start up the iMac Pro in Target Disk Mode. Connect it to another Mac running 10.13.4. Make sure that Mac also has an active Internet connection that can reach Apple’s servers.
As root:
asr restore --source osx_updated_180402-10.13.4-17E199.apfs.dmg --target /Volumes/Macintosh\ HD\ 1 --erase
Where --source points to the AutoDMG-generated deployment image, and --target points to the iMac Pro’s internal disk (mounted via Target Disk Mode). The restore session should look something like this:
# asr restore --source osx_updated_180402-10.13.4-17E199.apfs.dmg --target /Volumes/Macintosh\ HD --erase Validating target...done Validating source...done Erase contents of /dev/disk4s1 (/Volumes/Macintosh HD)? [ny]: y Retrieving scan information...done Validating sizes...nx_kernel_mount:1359: : checkpoint search: largest xid 72, best xid 72 @ 143 done Restoring ....10....20....30....40....50....60....70....80....90....100 Verifying ....10....20....30....40....50....60....70....80....90....100 Inverting target volume...done Remounting target volume...done Personalization over TDM succeeded
and you should have a working macOS 10.13.4 volume on the iMac Pro.
Managing OS X 