Where does SAP get its time from? 1

[Moose467]

Hi to all,
I have a simple question, I hope somebody can help.
Does anybody know where SAP gets its time from and more importantly how to change it.
In SP01 the generation time of spools is an hour behind the real time, I'm guessing as a result of moving to British Summer Time. I've checked the Unix Machine's and they all display the correct time.
Any thoughts would be grately appriciated.

Thanks

 

[bladesk8er]

SAP gets its time from the underlying database user I think.

I might be wrong, but I remember in the dim and distant past that UNIX runs on coordinated universal time, calculates the time based on the number of seconds its been since 1/1/1970 given the date and the time zone you're in, and whether Daylight Savings are in force. The SAP application may be getting the CUT and be in the wrong time-zone? What about other work processes? Do time stamps in dev trace files look correct relative to your time-zone? Did you restart your SAP after the system time changed?

On Unix, the ora<sid> user (if you use Oracle??) can also run in a different time zone as can the <sid>adm user.

So what you see when you say 'date' to your unix o/s can be different to what the database sees, and different again from what the sap system sees as the date.

Check out the environment variables for your db and sap users.

Here's some info from sapnet relating to time changes, last updated March 2002:

1. During the time change, the local time changes in one jump, whereas the UTC (universal time coordinator, or GMT) does not change in one jump but continously.
2. The platform may only support the local time, and not UTC.
3. If UTC exists, then platform-specific time zone representations that may support automatic time changes also exist. Experience has shown that the time zones are normally not handled correctly.
4. In many places in the SAP System, times are saved as the local time, and are therefore not sensitive to time changes.
5. In the ABAP processor, the difference between UTC and the local time is saved in seconds and is probably not affected by the time change. The ABAP time, SY-UZEIT, is derived from the data base time. The error LARGE_TIME_DIFF will probably occur.
6. Disturbances must be expected for batch jobs that are scheduled cyclically, as well as for cyclical background ABAPs, and so on.
7. There is a danger that backup and archive operations may become inconsistent.
8. Additional time-controlled operations must be considered:
Buffer synchronization
Refresh timer in the graphics module
Timeout monitoring
others

9. Timestamp-based dependencies may become inconsistent:
development objects, ABAP Dictionary objects, objects in applications

We recommend the following:
For the clock comparison in multi-computer configurations, deviations of a few seconds can be tolerated.
Changing the time in minutes (and more) and changes to the time zone settings require the SAP System to be restarted. The SAP System should not be active when the actual change is being made.
Changing from daylight saving time to winter time:
The SAP System should be switched off for two hours so you namely in the last hour of &quot;daylight saving time&quot; and the first hour of &quot;winter time&quot; (&quot;double hours&quot.
For more information refer to Note 102088.

Change from winter time to daylight saving time:
The system must be switched off during the change to the daylight saving time.
Solution
The time can not be changed while the R/3 System is running. The System must be restarted.