Technical data

Setting System Time
6.4 Setting Time in an OpenVMS Cluster Environment
6.4 Setting Time in an OpenVMS Cluster Environment
The local time, the TDF, and the time zone must be the same on all
nodes in an OpenVMS Cluster environment. You can use the System
Management utility (SYSMAN) DO command to invoke the command procedure
SYS$MANAGER:UTC$TIME_SETUP.COM on one node in a cluster to perform
the following actions for one or more nodes in the cluster:
• Display time zone information
• Set or change the time zone information
Because SYS$MANAGER:UTC$TIME_SETUP.COM is different on OpenVMS
Alpha systems and OpenVMS VAX systems, you must take care in a mixed
architecture cluster. Set the SYSMAN environment to operate on all Alpha or all
VAX nodes with the following SYSMAM command:
SYSMAN> SET ENVIRONMENT /NODE=(<node_list>)
Then, after you have run UTC$TIME_SETUP.COM for one architecture, reset the
environment to the other architecture and run UTC$TIME_SETUP.COM for that
architecture.
6.5 Adjusting for Daylight Saving Time
In time zones that use daylight saving time, your system time must be adjusted
twice a year. How this change occurs depends on the following:
• Whether DTSS is in use
• The version of OpenVMS
• The architecture (VAX or Alpha)
• System parameter AUTO_DLIGHT_SAV (OpenVMS Alpha Version 7.3 only)
Note
If you are using the Distributed Time Synchronization Service (DTSS),
DTSS makes the necessary changes between daylight saving time and
standard time. See Section 6.1.1.
If DTSS is not in use, use the following table to determine how to change system
time between standard time and daylight saving time:
OpenVMS Version Architecture AUTO_DLIGHT_SAV See
7.3 Alpha 1 Section 6.5.1
7.3 Alpha 0 Section 6.5.2
7.3 VAX n/a Section 6.5.2
7.2 and earlier VAX or Alpha n/a Section 6.5.3
6.5.1 Automatically Adjusting for Daylight Saving Time (OpenVMS Alpha
Version 7.3 Only)
OpenVMS Alpha Version 7.3 and later contain a system parameter, AUTO_
DLIGHT_SAV, that controls automatic switching between standard time and
daylight saving time.
Setting System Time 6–13