The clocks of all servers on the vSphere network must be synchronized. You can configure a Windows NTP client as a source for clock synchronization on Windows servers.

Use the registry editor on the Windows server to make the configuration changes.

1

Enable NTP mode.

a

Go to the registry setting HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Parameters

b

Set the Type value to NTP.

2

Enable the NTP client.

a

Go to the registry setting HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Config

b

Set the AnnounceFlags value to 5.

3

Enter the upstream NTP servers to synchronize from.

a

Go to the registry setting HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\TimeProviders.

b

Set the NtpServer value to a list of at least three NTP servers.

For example, you might set the value to 0x1 1.pool.ntp.org,0x1 2.pool.ntp.org,0x1 3.pool.ntp.org.

4

Specify a 150-minute update interval.

a

Go to the registry setting HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\TimeProviders\NtpClient,

b

Set the SpecialPollInterval value to 900.

5

Restart the W32time service for the changes to take effect.