I've finally been able to install NetBSD 9 in a VM. I've had tons of problems with package installation but these seem to have been addressed. The only remaining issues are frequent stale downloads, preventing scripted installation. Anyway, it's time for the next step: installation on real hardware.
I've installed NetBSD on an external USB disk and made sure its /etc/fstab was correct. However, when I reboot on this disk, I have a "Heap full" error and the machine boots on its internal disk.
If I drop to the boot prompt and type "boot hd0:", NetBSD boots normally.
My guess is that I need to set some obscure option in some configuration file. With FreeBSD, I need to set vfs.mountroot.timeout="10" in /boot/loader.conf. With OpenBSD, I don't need to do anything.
Can someone tell me what I should do for NetBSD in this case?