HP-UX Internet Services Administrator's Guide (February 2007)

Table 4-6 Restrict Option Flags (continued)
EffectFlag
Provide time service, but do not form peer association.
nopeer
Do not use the host as a synchronization source.
notrust
A restriction list entry with no flags set leaves matching hosts unrestricted. A source
address of an incoming packet may match several entries in the restriction list. The
entry that matches the source address most specifically is the entry that is applied. For
example, consider the following restriction list entries:
restrict 193.100.0.0 mask 255.255.0.0 ignore restrict 193.100.10.8
The first entry causes packets from source addresses on net 193.100 to be ignored.
However, packets from host 193.100.10.8 are unrestricted, as specified by the second
entry. The two restriction list entries effectively cause all packets from net 193.100 to
be ignored, with the exception of packets from host 193.100.10.8.
The following are examples of restriction list entries for a local host with the address
193.100.100.7. These entries assume that ntpq requests to the local host can be made
only from the local host or the host with address 193.8.10.1, while the local host only
synchronizes to a time source on net 193.100.
#default entry - matches *all* source addresses restrict default notrust nomodify
#trust for time, but do not allow ntpq requests restrict 193.100.0.0 mask 255.255.0.0 nomodify noquery
#ignore time requests, but allow ntpq requests restrict 193.8.10.1 noserve #local host address is unrestricted
restrict 193.100.100.7
Starting and Stopping xntpd
To start xntpd, do one of the following:
• Set the environment variable XNTPD to 1 in the file
/etc/rc.config.d/netdaemons. This causes xntpd to start automatically
when you boot the system.
• Issue the following command to run the xntpd startup script:
/sbin/init.d/xntpd start
You can specify command-line arguments for starting xntpd with the XNTPD_ARGS
environment variable in the file /etc/rc.config.d/netdaemons. For more
information on command-line arguments, type man 1M xntpd manpage at the HP-UX
prompt.
Advanced NTP Topics 69