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Upstream: In this section, configure external NTP servers with which hosts NIOS-X servers will synchronize time.
Override: To override the global NTP properties, turn this toggle switch on.
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SERVER ADDRESS: Enter the IP address or the FQDN of the NTP server you want to use as the upstream NTP server.
AUTHENTICATION: To enable authentication for the NTP server, toggle the switch to Enabled (green). The default is Disabled.
AUTHENTICATION KEY: If you enable authentication for the NTP server, Enter the trusted key.
TYPE: If you enable authentication for the NTP server, select MD5 from the drop-down list. At this time, BloxOne The Infoblox Platform supports only MD5 hashing as the cryptographic protocol for authentication.
POOL: Select this checkbox to add this NTP server to the pool of NTP servers. When you select this option, you can specify a pool of servers with which you can synchronize time.
BURST: Select this checkbox to configure the NTP client to send a burst of eight packets if the external NTP server is reachable and a valid source of synchronization is available. The NTP client transmits each packet every two seconds. When you clear this checkbox, the client sends a single packet to the server only once. A burst is used to accurately measure jitter with long-poll intervals.
IBURST: Select this checkbox to configure the NTP client to send a burst of eight packets if the external NTP server is not reachable when the client sends the first packet to the server. The NTP client transmits each packet every two seconds. If an NTP server is not responsive, the NTP client in IBURST mode will continue to send frequent queries until the server responds and time synchronization starts. If you deselect this checkbox, the client will send a single packet to the server only once.
PREFERRED: Select this checkbox to mark this external NTP server as the preferred NTP server. You can select only one server as the preferred NTP server.
Downstream: In this section, add trusted client keys to downstream NTP servers, if applicable.
Override: To override the global NTP properties, turn this toggle switch on.
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TYPE: Select MD5 from the drop-down list. At this time, BloxOne the Infoblox Platform supports only MD5 hashing as the cryptographic protocol for authentication.
KEY: Enter the trusted key.
Access Control & Rate Management: In this section, configure access control for the NTP service by enabling rate limiting and KOD (Kiss-O'-Death). The NTP access control list (ACL) specifies which clients can use a host NIOS-X server as an NTP server. If you do not configure access control, then BloxOne the Infoblox Platform will allow access to all clients. You can configure access control globally and override it for specific hostsNIOS-X servers. In addition, you can use one or more existing ACLs to control which clients can use the NTP service.
Override: To override the global NTP properties, turn this toggle switch on.
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