Based on the MAAS logs the halt happens after the remote shim, grub, and grub.cfg have been loaded. I didn't see anything in the console to show grub running but it may have been cleared before I could see it.
Console output: Booting local disk... Failed to open \efi\boot\grubx64.efi - Not Found Failed to load image \efi\boot\grubx64.efi: Not Found start_image() returned Not Found Bootloader has not verified loaded image. System is compromised. halting. rackd.log 2020-05-19 20:54:04 provisioningserver.rackdservices.tftp: [info] bootx64.efi requested by 10.0.0.117 2020-05-19 20:54:04 provisioningserver.rackdservices.tftp: [info] bootx64.efi requested by 10.0.0.117 2020-05-19 20:54:05 provisioningserver.rackdservices.tftp: [info] grubx64.efi requested by 10.0.0.117 2020-05-19 20:54:06 provisioningserver.rackdservices.tftp: [info] /grub/x86_64-efi/command.lst requested by 10.0.0.117 2020-05-19 20:54:06 provisioningserver.rackdservices.tftp: [info] /grub/x86_64-efi/fs.lst requested by 10.0.0.117 2020-05-19 20:54:06 provisioningserver.rackdservices.tftp: [info] /grub/x86_64-efi/crypto.lst requested by 10.0.0.117 2020-05-19 20:54:06 provisioningserver.rackdservices.tftp: [info] /grub/x86_64-efi/terminal.lst requested by 10.0.0.117 2020-05-19 20:54:06 provisioningserver.rackdservices.tftp: [info] /grub/grub.cfg requested by 10.0.0.117 2020-05-19 20:54:06 provisioningserver.rackdservices.tftp: [info] /grub/grub.cfg-00:16:3e:49:52:7b requested by 10.0.0.117 You can reproduce this pretty easily with MAAS 2.8 and LXD Pods. 1. Install MAAS 2.8 2. Add an LXD Pod 3. Compose a machine in the LXD Pod and let it commission 4. Reenable secure boot in the LXD virtual machine lxc config edit <vm name> Delete the line 'security.secureboot: "false"' 5. Attempt to deploy Ubuntu -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1865515 Title: Chainbooting from grub over the network to local shim breaks chain of trust To manage notifications about this bug go to: https://bugs.launchpad.net/maas/+bug/1865515/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs