Advisory: PureMessage, the possible effects of changes to Daylight Saving Time on PureMessage reporting

  • Article ID: 23877
  • Updated: 15 Mar 2010

If you are running PureMessage for Windows/Exchange, Sophos PureMessage Small Business Edition, or PureMessage for UNIX, you should take into account changes to and from daylight saving time (DST), which take place in March and October/November. The effects at each of these times will depend upon whether you are located in the northern or southern hemisphere.

Daylight saving time is a server and/or host operating system setting, and it should not affect the core operations of PureMessage.

Sophos recommends that you ensure that you are running the latest version of PureMessage.

What to do

PureMessage for Windows/Exchange and PureMessage Small Business Edition

Refer to the Microsoft Daylight Saving Time Help and Support Center, which explains in detail what action you may need to take.

PureMessage for UNIX

PureMessage for UNIX has no settings that make adjustments for daylight saving; it relies on the host operating system for time. Daylight saving affects servers that are set to local time instead of UTC, which may have a slight affect on the reporting subsystem. The full effects are noted below, according to whether your location is moving to or from daylight saving time.

Note: UNIX servers with time set to UTC are not affected by Daylight Saving.

Locations Entering Daylight Saving Time

In March this applies to locations in the northern hemisphere. It applies to the southern hemisphere in October/November. The following can be expected:

  • Core operations of PureMessage for UNIX are not affected.
  • A one-hour gap in reporting occurs because server's local time moves one hour ahead to reflect daylight saving time.
  • Some informational errors may appear in the pmx_err file. These errors can be ignored.

Locations leaving Daylight Saving Time

In March this applies to locations in the southern hemisphere. It applies to the northern hemisphere in October/November. The following can be expected:

  • Core operations of PureMessage for UNIX are not affected.
  • A two hour gap in reporting occurs because the server's local time is 'rewound' by one hour, to reflect the one-hour overlap. The PureMessage log files will retain the data.
  • Some informational errors may appear in the pmx_err file. These errors can be ignored.

 
If you need more information or guidance, then please contact technical support.

Rate this article

Very poor Excellent

Comments