NSX Advanced Load Balancer supports configuring NTP servers on SEs. Prior to this, NTP synchronization for SEs relied on the Controller as the NTP server and performed time synchronization on UDP port 123 over the management interface. The SE presumes network connectivity with the Controller.
NTP Configuration for SE deployed as a Virtual Machine
The SE NTP servers can be configured for the virtual machine and LSC-based deployments. The SE will synchronize time with the configured servers at start-up and periodically monitor the time sync status.
NTP Configuration for Virtual Machine Deployments
When SE is deployed as a virtual machine, NTP servers can be configured using any of the methods below and applies configuration in the following order of priority:
- DHCP
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If DHCP through dhclient provides NTP servers over the management interface, the SE uses DHCP provided NTP servers as configuration for SE NTP synchronization.
- Cloud Configuration
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If DHCP does not provide NTP servers, NTP servers are acquired from the cloud configuration. NTP server's configuration through cloud configuration is a bootup property, and the SE must be restarted to apply this configuration.
- Controller
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NTP servers configuration is through system configuration
NTP Server configuration through Cloud configuration using CLI is as follows:
[admin:ctrl]: > configure cloud Default-Cloud Updating an existing object. Currently, the object is: +------------------------------+--------------------------------------------+ | Field | Value | +------------------------------+--------------------------------------------+ | uuid | cloud-666c8a8f-341d-4225-a189-c128981130c7 | | name | Default-Cloud | | vtype | CLOUD_NONE | | dhcp_enabled | False | | mtu | 1500 bytes | | prefer_static_routes | False | | enable_vip_static_routes | False | | license_type | LIC_CORES | | state_based_dns_registration | True | | ip6_autocfg_enabled | False | | dns_resolution_on_se | False | | enable_vip_on_all_interfaces | False | | maintenance_mode | False | | tenant_ref | admin | | license_tier | ENTERPRISE | | autoscale_polling_interval | 60 seconds | | vmc_deployment | False | | metrics_polling_interval | 300 seconds | +------------------------------+--------------------------------------------+ [admin:ctrl]: cloud> ntp_configuration [admin:ctrl]: cloud:ntp_configuration> [admin:ctrl]: cloud:ntp_configuration> ntp_servers index 1 server 23.239.26.89 New object being created [admin:ctrl]: cloud:ntp_configuration:ntp_servers> save [admin:ctrl]: cloud:ntp_configuration> save [admin:ctrl]: cloud> save +------------------------------+--------------------------------------------+ | Field | Value | +------------------------------+--------------------------------------------+ | uuid | cloud-666c8a8f-341d-4225-a189-c128981130c7 | | name | Default-Cloud | | vtype | CLOUD_NONE | | dhcp_enabled | False | | mtu | 1500 bytes | | prefer_static_routes | False | | enable_vip_static_routes | False | | license_type | LIC_CORES | | state_based_dns_registration | True | | ip6_autocfg_enabled | False | | dns_resolution_on_se | False | | enable_vip_on_all_interfaces | False | | maintenance_mode | False | | tenant_ref | admin | | license_tier | ENTERPRISE | | autoscale_polling_interval | 60 seconds | | vmc_deployment | False | | metrics_polling_interval | 300 seconds | | ntp_configuration | | | ntp_servers[1] | | | server | 23.239.26.89 | +------------------------------+--------------------------------------------+ [admin:ctrl]: >
NTP Configuration for LSC (Baremetal) Deployments
When SE is deployed as a container on the Bare Metal, the administrator is required to configure the NTP servers on the host.
LSC NTP synchronization only supports the following NTP daemons:
- ntpd
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The Network Time Protocol daemon (ntpd) is an operating system program that maintains the system time in synchronization with time servers using the NTP.
- chronyd
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chronyd is another implementation of the NTP and is used:
To synchronize the system clock with NTP servers.
To synchronize the system clock with a reference clock, for instance, a GPS receiver.
To synchronize the system clock with a manual time input.
SE NTP operation
In both modes of deployments (SE deployed as a VM or as a container on LSC), SE periodically verifies if the NTP daemons can acquire and time sync with configured servers, and if SE is unable to sync time with the configured servers, an event is raised. The event is periodically repeated in 15 minutes unless the NTP time is synchronised.
