

To enable this feature, access the command-line interface in config mode and issue the command clock append. Note that the output of show clock and show log do not include timestamps, even when this feature is enabled. The timestamp feature can include a timestamp in the output of each show command issued in the command-line interface, indicating the date and time the command was issued. (host) (config) #ntp server Timestamps in CLI Output (host) (config) #ntp authentication-key md5 This example enables NTP authentication, add authentication secret keys into the database, and specifies a subset of keys which are trusted. The trusted key value must be numeric values between 1 to 65535. This is a subset of keys which are trusted. Under NTP Trusted Keys, enter a string in the Trusted Key field. The identification key along with its corresponding MD5 secret string is displayed in the NTP Identification Keys section. The MD5 ID key must be an ASCII string up to 31 characters. Then add a secret string in the MD5 Secret field. Under NTP Identification Keys, enter an identification key (a number between 5) in the Identification Key field. Under NTP Servers, enter the NTP server IP address in the Server IP field. Under NTP Authentication, make sure Enable is selected. This helps identify secure servers from fraudulent servers. The secret key is shared by both the controller and an external NTP server. NTP authentication works by using a symmetric key which is configured by the user. The Network Time Protocol adds security to an NTP client by authenticating the server before synchronizing the local clock. Ntp server ipaddr Configuring NTP Authentication Select (check) the iburst mode, if desired. If an NTP server is unresponsive, the iburst mode continues to send frequent queries until the server responds and time synchronization starts. The iburst mode is a configurable option and not the default behavior for the controller, as this option is considered “aggressive” by some public NTP servers. (When iburst mode is not enabled, only one query is sent within the first minute to the NTP server.) After the first minute, the iburst mode typically synchronizes the clock so that queries need to be sent at intervals of 64 seconds or more. The iburst mode sends up ten queries within the first minute to the NTP server. Configure the controller to set its system clock using NTP by configuring one or more NTP servers.įor each NTP server, you can optionally specify the NTP iburst mode for faster clock synchronization. You can use NTP to synchronize the controller to a central time source. To set the time zone and daylight savings time adjustment, enter the following commands in configure mode: To set the date and time, enter the following command in privileged mode: Additional fields appear that allow you to set the offset from UTC, and the start and end recurrences. To adjust the clock for daylight savings time, click Enabled under Summer Time. Under Time Zone, enter the name of the time zone and the offset from Greenwich Mean Time (GMT). Under Controller Date/Time, set the date and time for the clock. Navigate to the Configuration > Management > Clock page. You can use either the WebUI or CLI to manually set the time on the controller’s clock. You can set the clock on a controller manually or by configuring the controller to use a Network Time Protocol (NTP) server to synchronize its system clock with a central time source. Setting the System Clock Setting the System Clock
