Setting NTP Server on VNX5500

If your current time is ahead then what NTP typically does is not to jump back in time but rather slow down the clock till its correct

There are two times on a Block only VNX:

Internal Time or SP time - this should always be in UTC - when logs are created on the array (SP collects and NAr files), support assumes that the time in the logs are in UTC.

Unisphere Time: The time you see in the Unisphere GUI is dependent on the workstation you use to acess the array. Unisphere will take the time zone of your workstation and add/subtract from the Internal time to display the GUI time in your time zone. Internal time does not change, it always remains in UTC unless you change the time on the array to a different hour.

For example, if you are located in EDT (New York) time and your workstation is set to Eastern Time zone, when you access the array using Unisphere, the time displayed in Unisphere will be adjusted to display the time in Eastern Time.  If you change the time in Unisphere to a different hour - say you set the time ahead by 2 hours even though your workstation is set to Eastern Time, what you've done is to change the Internal time by +2 hours, thereby changing the times in the logs.

glen

Hi Glen, Thanks for all the info. My original reason for asking was, will there be any problems on the array if I change the incorrect time (5hrs ahead) to the correct time? We are located in the UK so should only ever be 1hr out between GMT and BST (Summer time).

No - just the internal logs will change.

If you have processes that run automatically on the array such as Auto-tiering or Mirrorview/Aync, these will now run at different times, but they should get back to a normal schedule once you change the time. Auto-tiering is by default set to start at 03:00 UTC, so you might want to see if that would interfere with some external backup at the same time.

glen