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While testing cannot substitute for investigating code for year
2000 problems, you can identify potential year 2000 problems by testing software in
an artificial environment that simulates future dates. The OpenVMS operating system allows
you to set the system clock forward and backward, which provides an appropriate environment
for system testing. The following procedure describes a technique for protecting your environment
while testing applications for the Year 2000.
Many system applications and layered products are affected
by any substantial modification of system time,
independent of the change to the Year 2000. The following procedure includes
guidelines that minimize side-effects that may occur due to these time
modifications. Digital recommends that you follow these guidelines to
ensure system integrity.
Caution
Do not perform Year 2000 tests or widely vary the system clock
on a system in a production environment.
Follow this procedure to test your system:
- Ensure that installed Product Authorization Keys (PAKs) will not
expire during the testing period. If your system has temporary PAKs,
contact your application vendor.
- Perform a complete backup of the system disk and associated data
disks. (If possible, back up to spare disks.)
- Remove the system to be tested from the production environment
to ensure data integrity during the test session. For example,
shut down all network connections as well as any local NTP or
DECdts processes before changing the system clock.
Nodes running NTP or DECdts clients or servers participate
in maintaining system time across the network; their presence
could either reset the clock to the current time or could serve a
future time to all other nodes in the network.
-
To ensure that the system time is reset before
any application code is started,
use the following commands to perform a conversational boot of your
backup copy of the system disk:
On VAX: >>> b/r5:1
On Alpha: >>> b -fl 0,1
Also set the SETTIME system parameter to 1:
SYSBOOT> SET SETTIME 1
SYSBOOT> CONTINUE
Then respond to the time prompt later in the bootstrap operation.
Some VAX or Alpha consoles may require different commands.
Consult the OpenVMS installation and upgrade documentation
for your specific Alpha or VAX processor.
-
Once the system has bootstrapped, mount the backup copies
of any other necessary data disks.
- Initialize and complete tests for your specific environment.
Among other dates, we have found the following transition
dates interesting to test:
-
September 9, 1999 to September 10, 1999
to confirm correct translation of 9/9/99)
-
December 31, 1998 to January 1, 1999
(to check whether 99 is used to mean "no expiration date")
-
December 31, 1999 to January 1, 2000
(to check century transition; January 1 should be a Saturday)
-
February 28, 2000 to February 29, 2000
(to verify leap year calculation; Tuesday,
February 29, 2000 is a valid date in the Gregorian calendar)
-
February 29, 2000 to March 1, 2000
(to verify leap year calculation;
March 1 should be a Wednesday)
These dates are only suggestions; more testing of later dates might be
required to thoroughly test your applications.
NOTE: DIGITAL recommends limiting all Year 2000 testing to dates
prior to 19-JAN-2038. Another industry-wide, date-related
problem will likely occur on that date at 03:14:07 GMT.
The Year 2038 problem is analogous to the Year
2000 problem, but results from overflows in the storage of time
and date values in C programs. The Year 2038 problem is expected
to have minimal adverse effects for the OpenVMS operating system
because the C date format is not the native date storage format used
on OpenVMS.
- When testing is complete, shut down the system.
Then mount and/or restore the original system disk and
all associated data disks.
(If you backed up your disks on tape instead of disk, restore the
original system disk and all original data
disks from your backup tapes.)
- Reboot the restored system.
To ensure that the rebooted system has the correct time
loaded, DIGITAL recommends that you perform a conversational
bootstrap operation with the
SYSGEN parameter SETTIME set to 1:
On VAX:
>>> b/r5:1
On Alpha:
>>> b -fl 0,1
SYSBOOT> SET SETTIME 1
SYSBOOT> SET WRITESYSPARAMS 0
SYSBOOT> CONTINUE
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