Thank Wright!/var/log/installer/syslog might not be helpful, because everything proceeds smoothly and normally during installation
it is easy to reproduce my problem, pc with 2 hard disks, 2 free usb disks(one for installation disk, the other installation target), i don't use uefi
actually i have installed freebsd on it, it fail to boot even though it has only 1 hard disk during installation
this new usb stick is so troublesome i might as well give up (use it as data storage only)
