Tag Archives: dr who

exchange,windows and the terrifying leap second.

This leap second thing…

Baffling.

We had one in 2012. and in 2008.

I may be wrong, but I don’t recall the world ending. I’d look out the window and check, but I’m in Stevenage, so that might not be as informative as I’d hope.

Clocks get moved about all the time in exchange; just have a look on virtualised systems for this event:

Information

########

Microsoft-Windows-Kernel-General

1

None

The system time has changed to ‎2015‎-‎01‎-‎19T14:31:54.447000000Z from ‎2015‎-‎01‎-‎19T14:31:51.850000000Z.

Look! That exchange server *went back in time* to 3 seconds before. It is Dr Who’s mail server. So long as it isn’t enough to break Kerberos, it’ll be fine. (1 second forward won’t break kerb.)

We’ve seen shifts of six and seven minutes on some of our customers, and that causes issues, especially in DAGs; just one of the reasons I really really hate virtualised exchange servers.

Anyway, here are some links on it:

What’s all this about the Leap Second, and how does it affect the Microsoft Windows OS and other products?

How the Windows Time service treats a leap second

http://en.wikipedia.org/wiki/Leap_second

 

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