Default Ntp Configuration; Configuring Ntp - Cisco WS-C4003 - Catalyst 4000 Chassis Switch Software Configuration Manual

Default NTP Configuration

machines with an association. However, in a LAN environment, you can configure NTP to use IP
broadcast messages. With this alternative, you can configure the machine to send or receive broadcast
messages, but the accuracy of timekeeping is marginally reduced because the information flow is
one-way only.
Cisco's implementation of NTP does not support stratum 1 service; it is not possible to connect to a radio
or atomic clock. We recommend that you obtain the time service for your network from the public NTP
servers available on the IP Internet.
If the network is isolated from the Internet, Cisco's NTP implementation allows a machine to be
configured so that it acts as though it is synchronized using NTP, when it actually has determined the
time using other methods. Other machines synchronize to that machine using NTP.
Default NTP Configuration
Table 35-1
Table 35-1 NTP Default Configuration
Feature
Broadcast client mode
Client mode
Broadcast delay
Time zone
Offset from UTC
Summertime adjustment
NTP server
Authentication mode

Configuring NTP

These sections describe how to configure NTP:
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Software Configuration Guide—Catalyst 4000 Family, Catalyst 2948G, Catalyst 2980G, Releases 6.3 and 6.4
35-2
shows the default NTP configuration.
Configuring NTP in Broadcast-Client Mode, page 35-3
Configuring NTP in Client Mode, page 35-3
Configuring Authentication in Client Mode, page 35-4
Setting the Time Zone, page 35-5
Enabling the Daylight Saving Time Adjustment, page 35-5
Disabling the Daylight Saving Time Adjustment, page 35-7
Clearing the Time Zone, page 35-7
Clearing NTP Servers, page 35-7
Disabling NTP, page 35-8
Chapter 35
Default Value
Disabled
Disabled
3000 microseconds
Not specified
0 hours
Disabled
None specified
Disabled
Configuring NTP
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