Implementing and Operating Cisco Enterprise Network Core Technologies (ENCOR) v1.2InfrastructureMedium
A network administrator needs to ensure that all network devices in a large enterprise network are synchronized to a common, accurate time source. The administrator wants to configure the Cisco routers and switches to act as NTP clients and receive time from a central NTP server. Which command sequence would correctly configure a device as an NTP client, assuming the NTP server's IP address is 10.0.0.1?
- Arouter(config)# service ntp server
- Brouter(config)# ntp master 10.0.0.1
- Crouter(config)# clock timezone EST -5
- Drouter(config)# ntp server 10.0.0.1 prefer
Show answer & explanationAnswer & explanation
Correct answer: D. router(config)# ntp server 10.0.0.1 prefer
The 'ntp server' command is used to configure a device as an NTP client, pointing it to a specified NTP server. The 'prefer' keyword can be added to indicate a preferred server among multiple configured servers.
Why the other options are wrong
- A. The 'service ntp server' command enables the device to act as an NTP server, allowing other devices to sync from it, not to sync from an external server.
- B. The 'ntp master' command configures the device to act as an authoritative NTP server itself, which is not the requirement here (client role).
- C. This command sets the local timezone, which is important for accurate time display but does not configure the device as an NTP client.
NTP Client Configuration
NTP client configuration involves instructing a network device to synchronize its clock with one or more designated NTP servers to maintain accurate time.
- Uses 'ntp server <IP_address>' command.
- Device syncs its time with the specified server.
- 'prefer' keyword can designate a primary server.
- Essential for logging, security, and troubleshooting.
Memory trick: To be a client, 'server' is the key, to get time, not give it for free.