The TrueNAS installer doesn't have a way to use anything less than the full device. This is usually a waste of resources when installing to a modern NVMe which is usually several hundred of GB. TrueNAS SCALE will use only a few GB for its system files so installing to a 16GB partition would be helpful.
Unfortunately this is only possible by using an intermediate device to act as the installation disk and later move this data to the NVMe.
Disable Secure Boot. ZFS modules can not be loaded if Secure Boot is enabled.
Before moving on I need to point out that there exists a script that can automate the configuration and install of a ZFS root system. However as convenient as it sounds the script is limited in flexibility and scope. These limitation cannot be overcome unless one has the time and compacity to edit the script to their liking. If you want to install a ZFS root system as quickly as possible and don't care about any particulars than take a good look at this github page.
| #!/bin/sh | |
| # vim: noexpandtab ts=8 sw=4 softtabstop=4 | |
| # Setup a semi-sane environment | |
| PATH=/sbin:/bin:/usr/sbin:/usr/bin | |
| export PATH | |
| HOME=/root | |
| export HOME | |
| TERM=${TERM:-xterm} |
