1Starting with NetBSD-1.6, it is possible to delegate the system clock 
2control to a non root user. This enable running ntpd in a chroot 
3jail under a non privilegied UID/GID, using ntpd -i and -u flags.
4
5The delegation is done through the clockctl(4) pseudodevice driver. 
6This driver makes privilegied system calls such as ntp_adjtime(2)
7available through ioctl(2) on the /dev/clockctl device. If a user
8is able to write to /dev/clockctl, then (s)he can control the system 
9clock.
10
11In order to use this feature, make sure that:
12
131) Your kernel is compiled with the following option:
14pseudo-device	clockctl
15This is true for GENERIC kernels on most ports. Please check 
16http://wwW.netbsd.org/Documentation/kernel/
17if you need information about building a kernel.
18
192) You have a ntpd user on your system. Here is the /etc/master.passwd
20entry for ntpd user on NetBSD-1.6:
21ntpd:*:15:15::0:0:& pseudo-user:/var/chroot/ntpd:/sbin/nologin
22And here is the /etc/group entry for group 15:
23ntpd:*:15:
24
253) /dev/clockctl exists and is writtable by user ntpd. Default 
26NetBSD-1.6 setting is:
27crw-rw----  1 root  ntpd  61, 0 Apr 1  2002 /dev/clockctl
28Major device number and date is likely to be different on your system.
29If you need to create the device, issue the following command:
30cd /dev && ./MAKEDEV clockctl
31
32Here is an example of how to run ntpd chrooted in /var/chroot/ntpd, 
33running with ntpd UID and ntpd GID:
34ntpd -i /var/chroot/ntpd -u ntpd:ntpd
35Note that -i and -u options are enabled at configure time if your 
36system supports system clock control by an unprivilegied user. If this
37is not the case, then the -i and -u options will not be available.
38