| Moving time forward or backward doesn't really cause problems for PCM.
When moving time backward, the time-stamp file will be "mis-ordered"
for at least an hour. This is because it is a sequential file. For
example, let's say you move the time back and hour at 2:00 AM in the
morning. You already have data present in the file from 1:00 AM through
2AM which is when you set the time back. Since you set it back an hour
you have obviously moved the clock back to 1:00 AM. So your going to
write have a timjes file that looks like this:
2:00 AM - time is changed back to 1:00 AM
12:00AM 1:00 AM |
|-----------|-----------|-------------|-----------|
|
1:00 AM 2:00 AM 3:00 AM
You will be able to use the EXTRACT interface but you would see the
output revert back to 1:00 AM right after 2:00 AM. The point here is
that someone could mistakenly think that PCM had a problem where it
wrote some data twice when, in fact, it did not.
The other issue would be with the archive facility. You would want to make
sure that when you do an archive against the active logfile that
contains the time-change that your archive encompasses the times when
the time was changed. For example, you would not want to do an archive
command like the the following.
CONS ARCHIVE/BEFORE=DD-MMM-YYYY:02:00
This command would only get the data before the time change.
Also take into account that archive files are named using the following
convention:
nodename.yymmddhhmm_TO_yymmddhhmm
If you repeated the archive command you could wind up with two archive
files with the same starting date/time.
A correct archive command would be:
CONSOLE ARCHIVE/BEFORE=DD-MMM-YYYY:03:00
or some later hour.
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