Implementing NTP on Cisco IOS XR Software
How to Implement NTP on Cisco IOS XR Software
The following are two most commonly used, poll-based association modes:
•Client mode
•Symmetric active mode
The client and the symmetric active modes should be used when NTP is required to provide a high level of time accuracy and reliability.
When a networking device is operating in the client mode, it polls its assigned time serving hosts for the current time. The networking device then picks a host from all the polled time servers to synchronize with. Because the relationship that is established in this case is a client-host relationship, the host does not capture or use any time information sent by the local client device. This mode is most suited for file-server and workstation clients that are not required to provide any form of time synchronization to other local clients. Use the server command to individually specify the time-serving hosts that you want your networking device to consider synchronizing with and to set your networking device to operate in the client mode.
When a networking device is operating in the symmetric active mode, it polls its assigned time-serving hosts for the current time and it responds to polls by its hosts. Because this is a peer-to-peer relationship, the host also retains time-related information about the local networking device that it is communicating with. This mode should be used when there is a number of mutually redundant servers that are interconnected via diverse network paths. Most stratum 1 and stratum 2 servers on the Internet today adopt this form of network setup. Use the peer command to individually specify the time-serving hosts that you want your networking device to consider synchronizing with and to set your networking device to operate in the symmetric active mode.
SUMMARY STEPS
1.configure
2.ntp
3.server ip-address[version number] [key key-id] [minpoll interval] [maxpoll interval] [source interface-typeinterface-instance] [prefer]
4.peer ip-address[version number] [key key-id] [minpoll interval] [maxpoll interval] [source interface-typeinterface-instance] [prefer]
5.end or commit
DETAILED STEPS
| Command or Action | Purpose |
Step 1 | | |
configure | Enters global configuration mode. |
| Example: | |
| RP/0/RP0/CPU0:router# configure | |
Step 2 | | |
ntp | Enters NTP configuration mode. |
| Example: | |
| RP/0/RP0/CPU0:router(config)# ntp | |
| | |
Cisco IOS XR System Management Configuration Guide
SMC-172