These are the parameters I used to get a successful deployment with the autoinstall ISO:
OS Type: Linux
BIOS: OVMF (UEFI)
SCSI: VirtIO SCSI single
Disk Bus/Device: SCSI 0
Disk Size: 1024 GiB (1 TiB)
CPU: 2 sockets, 8 cores
CPU type: host
Memory: 65536 MiB RAM (64 GiB)
Network: VirtIO
These are the parameters I used to get a successful deployment with the autoinstall ISO: OS Type: Linux BIOS: OVMF (UEFI) SCSI: VirtIO SCSI single Disk Bus/Device: SCSI 0 Disk Size: 1024 GiB (1 TiB) CPU: 2 sockets, 8 cores CPU type: host Memory: 65536 MiB RAM (64 GiB) Network: VirtIO
CPU type host allows nested virtualization for the guest. You may also need to make sure Nested Hardware-assisted Virtualization is enabled on the host: https://pve.proxmox.com/wiki/Nested_Virtualization#Enable_Nested_Hardware-assisted_Virtualization
UEFI seems to be mandatory, in BIOS mode it fails to create the boot partition.