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Table Of Contents
This task explains how to set up NTP from the VMware Host Client. You can instead use the vicfg-ntp
vCLI command. See the vSphere Command-Line Interface Reference.
Procedure
1 Start the VMware Host Client, and connect to the ESXi host.
2 Click Configure.
3 Under System, click Time Configuration, and click Edit.
4 Select Use Network Time Protocol (Enable NTP client).
5 In the Add NTP Server text box, enter the IP address or fully qualified domain name of one or more
NTP servers to synchronize with.
6 (Optional) Set the startup policy and service status.
7 Click OK.
The host synchronizes with the NTP server.
Configuring Time Synchronization Settings in the
vCenter Server Appliance
You can change the time synchronization settings in the vCenter Server Appliance after deployment.
When you deploy the vCenter Server Appliance, you can choose the time synchronization method to be
either by using an NTP server or by using VMware Tools. In case the time settings in your vSphere
network change, you can edit the vCenter Server Appliance and configure the time synchronization
settings by using the commands in the appliance shell.
When you enable periodic time synchronization, VMware Tools sets the time of the guest operating
system to be the same as the time of the host.
After time synchronization occurs, VMware Tools checks once every minute to determine whether the
clocks on the guest operating system and the host still match. If not, the clock on the guest operating
system is synchronized to match the clock on the host.
Native time synchronization software, such as Network Time Protocol (NTP), is typically more accurate
than VMware Tools periodic time synchronization and is therefore preferred. You can use only one form of
periodic time synchronization in the vCenter Server Appliance. If you decide to use native time
synchronization software, vCenter Server Appliance VMware Tools periodic time synchronization is
disabled, and the reverse.
Use VMware Tools Time Synchronization
You can set up the vCenter Server Appliance to use VMware Tools time synchronization.
Procedure
1 Access the appliance shell and log in as a user who has the administrator or super administrator role.
The default user with super administrator role is root.
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