Time synchronization

Installing an HCP system

Part Number

You need to decide whether the HCP system should use itself as a time source or should use one or more external time servers. When the time source is internal, the nodes synchronize time among themselves. Because HCP is a closed system, making the time source internal ensures compliance with the applicable regulations.

On the other hand, using internal time can result in clock drift, thereby causing HCP system time to differ from the time settings of other applications in the corporate environment. Resetting the HCP system time to compensate for this drift can affect object retention, thereby violating compliance.

External time servers can be corporate or Internet time servers. Using a corporate time server keeps the HCP system time synchronized with other applications in the corporate environment. However, if the corporate time server is not completely secure, compliance is not guaranteed. The same concern about compliance applies to Internet time servers. Using multiple external time servers helps ensure the integrity of the time source.

  • HCP does not support using Windows as an external time server.
  • To ensure proper system time synchronization, HCP each external time server must have a minimum stratum of 10. For best results, use external time servers that have a minimum stratum of 5 or less.
  • When HCP is using an external time server, if either of the following happens, the HCP system automatically restarts itself:
    • The time on the time server is changed by more than 1,000 seconds.
    • The HCP system switches to a different time server whose time differs from the original time server by more than 1,000 seconds.
  • For HCP to use Windows Active Directory for user authentication, the HCP system time must be the within 5 minutes of the Active Directory time. The best-practice configuration is for HCP and Active Directory to use the same external time server.

To set the time source during a software installation, you specify either internal or the IP addresses or hostnames of the external time servers that you want to use. If you specify internal, you also need to supply the initial time to which the nodes should synchronize.

  • You can specify an external time server during HCP installation only if the HCP system already has connectivity to the time server through the [hcp_system] network.
  • HCP creates a comma-delimited list of the external time server IP addresses and hostnames that you specify during the HCP software installation. The comma-delimited list of external time servers can be at most 143 characters long (including the commas).
  • If the front-end network IP mode is set to Dual, you can specify both IPv4 and IPv6 addresses for one or more external time servers.

If you start the HCP software installation within the same installation program session in which you specify the initial system time, the installation program adjusts the specified time to account for the time that elapses between when you specify the initial system time and when the program actually installs the software.

Regardless of the time source, you also need to specify a time zone for the HCP system. Normally, this is the time zone in which the system is located.

The installation program can present a list of time zones in which you can find the exact text for the one you want to use. You can also find lists of time zones on the Internet.

The System Management Console includes a page for changing the time settings for the HCP system. This page is intended for use only by authorized HCP service providers.

Changing time settings after the system is installed has certain implications and might cause the system to no longer be in compliance with some government regulations. Because of this, you can configure the HCP system not to allow changes to time settings through the Console. In this case, the system is said to be in time compliance mode. Before you install the HCP software, you need to decide whether the system should be in this mode.