Global NTP Configuration
- Shirly Tsang
Analytics
Before deploying the NTP service, it is good practice to configure the Global NTP settings. This is not required; however, all new deployments will source their initial configuration from these settings. If desired, these settings may be overridden at a local level when creating or editing an NTP service.
Navigate to the NTP page. Highlight Manage, then click NTP.
In the Upstream section an external NTP server may be added. For the operation of each NTP service to be successful, at least one NTP server must exist in the Upstream section either locally, or globally.
To add an Upstream server, click the Add External NTP Servers button.
In the Server Address textbox, input an FQDN or IP address of an external NTP server.
(Optional) If Authentication is desired click the Toggle switch to enable Authentication.
If Authentication is enabled, input a MD5 Trusted Authentication key in the Authentication Key textbox. Note: This key is acquired from the administrator of a third-party NTP server you are adding as an External NTP server.
For Type select MD5 via the Dropdown menu.
(Optional) Click the Pool checkbox to add the NTP server to a pool. When this checkbox is enabled, this server is added to a pool of servers which devices can synchronize time with.
(Optional) Click the Burst checkbox to enable the Burst setting. Note: by enabling Burst, the NTP client will send a burst of eight packets if the External NTP server is reachable, and a valid source of synchronization is available. These packets are sent at the interval of every 2 seconds. This setting is used to measure jitter.
(Optional) Click the IBurst checkbox to enable the IBurst setting. Note: By enabling IBurst, the NTP client will send a burst of eight packets if the External NTP server is not reachable when the client sends the first NTP packet to the server. These packets are sent at the interval of every 2 seconds. Packets are continually sent until the NTP server is reachable. If the NTP server remains unreachable, BloxOne will utilize another upstream server, or default to the local clock of the OPH with NTP enabled.
(Optional) Click the Preferred checkbox to make this External NTP server the preferred external NTP server. Note: This setting forces the existing NTP servers to sync with this server instead of potential alternatives. You may only select one external NTP server as a preferred server.
(Optional) Below the Downstream header, a trusted client key can be added. Note: when you configure a trusted client key, this key is used to authenticate an external third-party NTP server that will attempt to sync NTP data with BloxOne. This key is acquired from the third-party NTP server.
To add a trusted client key, click via the Add Key button.
After clicking the Add Key button, input the following data to add a trusted client key:
Select MD5 via the Type dropdown menu.
Input the key in the Key textbox. Note: This key is acquired from the NTP server you are adding as a Downstream NTP server.
(Optional) Input a comment in the Comments field. Note, a comment is a way to input a description of the key.
Under the Access Control & Rate Management header the following settings are configurable (Note: Currently Add ACL, Remove ACL, and ACL selection are not configurable):
(Optional) If you wish to enable Rate Limiting, click the toggle switch associated with the Rate Limit Status column. Note: this setting enables BloxOne NTP servers to not respond when a packet violates the rate limit specified in the Inter Packet Spacing (seconds) section.
(Optional) To enable the KoD status, click the toggle switch associated with the KoD Status column. Note: in order to enable this setting, the Rate Limit status must be set to ‘enabled’. The KoD status or Kiss-o’-death status setting allows for the KoD packet to be sent to NTP servers that exceed the rate limit that is specified.
(Optional) Under the Inter Packet Spacing (seconds) header, the following rate limiting parameters can be set. Note: in order to change these settings, the Rate Limit status must be set to ‘enabled’. Inter-packet spacing is the pause between NTP packets.
(Optional) Input the permitted Average time between NTP packets via the Average textbox. Note: this setting sets the minimum allowed average time in seconds for an inter-packet pause between two NTP packets. The default for this setting is 3 seconds.
(Optional) Input the permitted Minimum time between NTP packets via the Minimum textbox. Note: this setting sets the minimum allowed time in seconds for an inter-packet pause between two NTP packets. The default for this setting is 1 second.
(Optional) Input the Monitor time via the Monitor textbox. Note: this setting defines the amount of time in seconds after the rate limit has been exceeded by a server before accepting packets again from that same server. The default for this setting is 3000 seconds.