variantolog unlike Solaris, Linux or FreeBSD, NetBSD doesn't come with a devfs virtual filesystem to dynamically create/manage namespaces for devices1. /dev is populated with static device nodes upon installation, using the MAKEDEV script (which by default only creates cgd*[^0-3]). If required, any additional node can be generated with MAKEDEV.local(8). Also see mknod(2).
1 Even though namespaces for pluggable storage devices and peripherals can be dynamically assigned by enabling the devpubd(8) service, which acts like a device state event change deamon.