Setting The System Time Through Ntp - Cisco Catalyst 2000 Configuration Handbook

(including the words "first" and "last"), the name of the day, the name of the month,
and time hh:mm in a 24-hour format. If no arguments are given, the U.S. standard of
beginning at 2:00 a.m. on the first Sunday in April, and ending at 2:00 a.m. on the
last Sunday in October is used. The offset value can be given to set the number of
minutes that are added during DST (default 60 minutes).
Otherwise, you can use the date keyword to specify the exact date and time that
DST begins and ends in a given year.
(Optional) Set the system clock (IOS clock):
3.
(exec) clock set hh:mm:ss [day month | month day]
The clock is set when this command is executed. The time is given in a 24-hour for-
mat; day is the day number, month is the name of the month, and year is the full
four-digit year.
(Optional) Set the system calendar (hardware clock):
4.
(exec) calendar set hh:mm:ss [day month | month day] year
The hardware clock is set to the given time (24-hour format) and date. The month is
the name of the month, day is the day number, and year is the full four-digit year.
As an alternative, you can set the system calendar from the system clock using the
(EXEC) clock update-calendar command.

Setting the System Time Through NTP

Define one or more NTP peer associations:
1.
(global) ntp peer ip-address [version number] [key keyid] [source interface]
[prefer]
The NTP peer is identified at ip-address. The NTP version can be given with the
version keyword (1 to 3, default is version 3). If NTP authentication is used, the key
keyword identifies the authentication key to use (see Step 3b in this section). If
desired, you can take the source address used in NTP packets from an interface by
using the source keyword. Otherwise, the router uses the source address from the
outbound interface. The preferred keyword forces the local router to provide time
synchronization if contention exists between peers.
(Optional) Configure the NTP broadcast service:
2.
(global) ntp broadcast client
(global) ntp broadcastdelay microseconds
By default, NTP sends and receives unicast packets with peers. Broadcasts can be
used instead if several NTP peers are located on a common network. The ntp broad-
cast command enables sending broadcast packets. The ntp broadcast client com-
mand enables the reception of broadcast packets. The ntp broadcastdelay command
sets the round-trip delay for receiving client broadcasts (1 to 999,999 microseconds;
default is 3000 microseconds).
Chapter 3: Supervisor Engine Configuration 49
year