macOS 10.13.4 imagetool/System Image Utility failing checksum when creating NetRestore images

Number:rdar://39322132 Date Originated:4/10/2018
Status:Closed Resolved:No
Product:macOS + SDK Product Version:macOS 10.13.4 (17E199), System Image Utility 10.13 (829)
Classification:Bug Reproducible:Always
Something not on this list

When a Mac running macOS 10.13.4 attempts to capture a NetRestore image, it consistently fails during the System.dmg block checksum step with error 2. Issue occurs with multiple source Macs and multiple 10.13.4 capture Macs. macOS 10.13.3 SIU is able to capture the same Macs for NetRestore without error.

Steps to Reproduce:
1. Boot a source Mac with desired custom configuration in Target Disk Mode and attach it to a Mac running macOS 10.13.4.
2. Open System Image Utility.
3. Configure SIU to create a NetRestore image using the source Mac.
4. Observe failed block checksum and error code.

Expected Results:
NetRestore image should be created at target path using source Mac's filesystem.

Actual Results:
SIU fails block checksum of System.dmg file created from source Mac (failure occurs at very end of block checksum step), ends sequence with error 2, then deletes System.dmg.

Both the source Mac and the Mac running SIU are running macOS 10.13.4 (17E199). System Image Utility version is 10.13 (829).

Source Mac has a fresh install of macOS 10.13.4 with a local admin account created in Setup Assistant.


Reply from Apple Developer Relations

There are no plans to address this.

We are now closing this report.

If you have questions about the resolution, or if this is still a critical issue for you, then please update your bug report with that information.

Please be sure to regularly check new Apple releases for any updates that might affect this issue.

By mpanighetti at April 25, 2018, 11:46 p.m. (reply...)

HFS+ works, APFS does not

I witnessed the exact problem. However, I discovered that if the source Mac is HFS+ formatted, it works. When the Source Mac is APFS, it errors on the command, "asr imagescan"

Preparing image for restore + /usr/sbin/asr imagescan --source /Volumes/4TB/Library/NetBoot/NetBootSP0/HighSierraAPFS.nbi/System.dmg Block checksum: ....10....20....30....40....50....60....70....80....90....100asr: image scan failed - internal error. + mnrfiErrExit + '[' VERBOSE '!=' DEBUG ']' + echo 'Execution of '''''' failed. Cleaning up.' Execution of '' failed. Cleaning up. + /bin/rm /Volumes/4TB/Library/NetBoot/NetBootSP0/HighSierraAPFS.nbi/System.dmg + exit 1 + afvErrExit + '[' VERBOSE '!=' DEBUG ']' + echo 'Execution of '''''' failed. Cleaning up.' Execution of '' failed. Cleaning up. + '[' NO == YES ']' + exit 1 ++ exit 1

Note that 10.13.4 SIU Macs are also failing to capture 10.13.3 source Macs. Haven't tested with additional older macOS builds, but I would suspect this is a general issue with imagetool in 10.13.4 and not dependent on specific source Mac builds.

By mpanighetti at April 11, 2018, 11:46 p.m. (reply...)

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