Upgrade NetBSD from binary sets
Upgrading the system from binary sets it's a quite straightforward process. Here are the steps.
Perform a minimal safety backup
$ tar zcvf etc-backup.tar.gz /etc
$ cp /netbsd /netbsd.old
Upgrade the system
$ tar zxvpf kern-GENERIC.tgz -C /
$ tar zxvpf base.tgz -C /
$ tar zxvpf comp.tgz -C /
$ tar zxvpf text.tgz -C /
$ tar zxvpf games.tgz -C /
Upgrade configuration files
Assuming etc.tgz and xetc.tgz are stored in /home/adotti/sets:
$ etcupdate -av -s /home/adotti/sets/etc.tgz -s /home/adotti/sets/xetc.tgz
Additional notes
If the upgrade involves a major version (from 2.x to 3.x for example), the system must be rebooted right after the new kernel has been installed, and before upgrading the base system, otherwise erratic behaviours may occur.
After the upgrade process, beside etcupdate, it is also advisable to
run postinstall to check if any old and useless files were left
around, and to perform other cleanup tasks.