VMS - change from EDT to EST - have question about daylight_savings.com

[Layne Burleson_1]

When I use sys$examples:daylight_savings.com, I have no problem converting from eastern daylight to eastern standard. However, when I do the reverse by changing from standard to daylight, the following 2 logicals do not get changed: SYS$TIMEZONE_DAYLIGHT_SAVINGS and SYS$TIMEZONE_NAME. They remained the same and should have changed. I'm on Alpha DS10 running OpenVMS 7.3-1 fully patched.... does anyone have a better method for time change. We do not run DTSS and can't turn on the automatic time change system parameter due to manufacturing schedules.

[Volker Halle]

Layne,

looks like the new (E8.2) DAYLIGHT_SAVINGS.COM now also resets the 3 logicals:

$! SYS$TIMEZONE_DAYLIGHT_SAVING
$! SYS$TIMEZONE_NAME
$! SYS$TIMEZONE_RULE

by invoking @SYS$MANAGER:UTC$TIME_SETUP "" RULE

Volker.

[Ian Miller.]

Do you have NET$DISABLE_DTSS defined to be true?

I seem to remember reading somewhere that this should be defined explictly as well has not having dtss installed due to a check for it in a command file somewhere.

[Layne Burleson_1]

Ian,
No I don't have that defined. I just tried it out prior to running a the procedure and I get the same results.
Layne

[Volker Halle]

Layne,

from reading the E8.2 DAYLIGHT_SETTINGS.COM, you should do the following:

Just try to run @SYS$MANAGER:UTC$TIME_SETUP "" RULE
after @DAYLIGHT_SETTINGS.COM - this is the last line added to DST$CHANGE.COM in the E8.2 version.

As far as I'm aware, the only 'supported' way to disable DTSS is via DEF/SYSTEM NET$DISABLE_DTSS in SYLOGICALS.COM

Volker.

[Layne Burleson_1]

Volker-
I'm on 7.3-1, not Eval 8.2..... I need something that I can run in batch mode to change the information. I can pass in parameters to the daylight_savings.com, but I"m not sure what to pass to the other you recommended.
Layne

[Martin P.J. Zinser]

Hello Layne,

I think you misunderstood Volker. He does not (yet ;-) suggest to upgrade to 8.2.

But from looking at the code he sees that the difference between the two is the call to the
@SYS$MANAGER:UTC$TIME_SETUP DCL procedure at the end.

So if you do need to do this in a batch, just execute the two procedures one after another.

Greetings, Martin

[Volker Halle]

Layne,

Martin got it right ;-)

I looked at the differences between E8.2 and a previous version of DAYLIGHT_SAVINGS.COM and spotted the comments, which talked about setting those 3 additional logicals in 8.2. And I also found the additional call of @SYS$MANAGER:UTC_TIME_SETUP "" RULE

These changes will appear in the next version of OpenVMS V8.2 and - as this is just a DCL procedure - may be worth testing in your environment as well. If it works for you - and it should (otherwise you can send me a reproducer and I'll happily escalate this via PTR - we're a fieldtest site), then you're happy and we all know it will work for everybody in V8.2.

Volker.

[Layne Burleson_1]

Martin & Volker,
Thanks for the input. Excuse my ignorance, but what parameters are feed into sys$manager:Utc$time_setup. I had a system set to EST with differential of -18000.... I ran the daylight savings job for daylight savings and it set the differential to -14400 which is correct, but did not change any other logicals. I'm not sure what to put in the utc$time_setup for a batch run.

I thought it may be something like @sys$manager:utc$time_setup.com "" "TDF" -240 0 ...... but that did not change the sys$timezone_name or sys$timezone_daylight_saving logical to the correct values.

[Volker Halle]

Layne,

I would suggest, that you first try to manually invoke the procedure with the following DCL command:

$ @SYS$MANAGER:UTC$TIME_SETUP "" RULE

after running DAYLIGHT_SAVINGS.COM

If that works for you, you can think of just writing a new small DCL procedure, which invokes both procedures one after the other and submit that one in batch.

If you send me mail, I'll send you the E8.2 version of DAYLIGHT_SAVINGS.COM so you can test the new version yourself. You should be able to guess my mail address from looking at my forum profile...

Volker.

[Layne Burleson_1]

Volker,
I did a difference on the file you sent me and the file I have on 7.3-1. They are the same. I thought that to be rather weird.
Layne

[Martin P.J. Zinser]

Hello Layne,

now you made me do it ;-) I've actually looked at the procedure.

The invocation of utc$time_setup.com quoted by
Volker can be used verbatim. RULE is not some
symbol set earlier in the procedure but a keyword expected by utc$time_setup.com.

So go ahead, run it and check if your logicals get defined correclty.

Greetings, Martin

[Layne Burleson_1]

Martin,
I just ran and this is what I get:
$ sho lo *timez*

(LNM$PROCESS_TABLE)

(LNM$JOB_8132F740)

(LNM$GROUP_000001)

(LNM$GROUP_000250)

(LNM$SYSTEM_TABLE)

"SYS$TIMEZONE_DAYLIGHT_SAVING" = "0"
"SYS$TIMEZONE_DIFFERENTIAL" = "-18000"
"SYS$TIMEZONE_NAME" = "EST"
"SYS$TIMEZONE_RULE" = "EST5EDT4,M4.1.0/02,M10.5.0/02"

(LNM$SYSCLUSTER_TABLE)

(DECW$LOGICAL_NAMES)
$ sho time
9-NOV-2004 15:15:54
$ @sys$examples:daylight_savings.com

Are you changing to DAYLIGHT or to STANDARD time? (DAYLIGHT/STANDARD): DAYLIGHT

Will the sysman be on this NODE only or CLUSTER wide? (NODE/CLUSTER): NODE

If you choose to SAVE the procedures, you can modify
the SYSMAN environment, or make other changess before executing.

Do you wish to EXECUTE the change now, QUEUE it for future execution,
or SAVE the created procedures without executing?
(EXECUTE/QUEUE/SAVE): EXECUTE




Created file $1$DKA100:[VMS$COMMON.SYSMGR]DST$CHANGE.COM

Is it O.K. to execute the time sysman now? (Yes/No): YES

Configuring the Time Differential Factor (TDF)


$ @SYS$MANAGER:UTC$TIME_SETUP "" RULE

$ SHO LO *TIMEZ*

(LNM$PROCESS_TABLE)

(LNM$JOB_8132F740)

(LNM$GROUP_000001)

(LNM$GROUP_000250)

(LNM$SYSTEM_TABLE)

"SYS$TIMEZONE_DAYLIGHT_SAVING" = "0"
"SYS$TIMEZONE_DIFFERENTIAL" = "-14400"
"SYS$TIMEZONE_NAME" = "EST"
"SYS$TIMEZONE_RULE" = "EST5EDT4,M4.1.0/02,M10.5.0/02"

(LNM$SYSCLUSTER_TABLE)

(DECW$LOGICAL_NAMES)
$ SHO TIME
9-NOV-2004 16:17:04
$

Notice that the daylight savings and timezone name did not change to 1 and EDT.


I really appreciate your input.
Layne

[Volker Halle]

Layne,

it looks like you need to be in the appropriate time zone interval (EDT or EST), to allow the procedure to change those 2 logicals: SYS$TIMEZONE_DAYLIGHT_SAVINGS and SYS$TIMEZONE_NAME.

You tried to change to EDT (DAYLIGHT) on 9-NOV-2004, which is clearly outside the valid DST interval as defined in the rule:

SYS$TIMEZONE_RULE" = "EST5EDT4,M4.1.0/02,M10.5.0/02
(DST = Daylight Savings Time EDT goes from 1st sunday in April until last Sunday in October).

Try to set your system time to 1-OCT-2004 and then change to EDT (DAYLIGHT). Then set the time to 1-NOV-2004 and change to EST (STANDARD).

I tried this on my E8.2 system with MET and MET DST and those 2 logicals changed as expected.

You might want to do this on a test system to not confuse anything related to timestamps !

Volker.

[Volker Halle]

Layne,

your DAYLIGHT_SAVINGS.COM (dated 31-MAR-2004) has come from VMS731_TDF-V0500, so this explains why it could be the same version as included in E8.2

Volker.

[Layne Burleson_1]

Volker,

I think you have solved my problem.... Let me make sure I understand... The SYS$TIMEZONE_RULE determines when the logicals get set and since I am trying to run it outside of that window, it is not changing. Is it possible to modify that rule to run a test?

You have been most helpful and I really appreciate it.

Layne

[Volker Halle]

Layne,

yes, these are my conclusions from your (and my) experience when playing with DAYLIGHT_SAVINGS.COM - and it makes sense to me, that nobody has bothered to test switching to daylight savings time during the winter season ;-)

Changing the rule for a test (I assume you don't want to change the time too much):

I must admit, that I still have not fully understood, where the real source of the timezone rule definition is located.

If DECnet-OSI is installed and you're using DTSS, it seems to come from DTSS$TIMEZONE_RULES.DAT.

I only know that invoking @SYS$MANAGER:UTC$TIME_SETUP is the only supported and reliable way to change these settings in the running system.

Just re-defining the translation of SYS$TIMEZONE_RULE may not work, but you could try. I ran my tests on a test system after a minimum boot.

Volker.

[Layne Burleson_1]

Volker,
I'll try proceeding in that direction. I still run Decnet phase IV. I've got a contact in HP support that used to be my TAM. She is working on a timezone problem and I've asked her to explain the timezone rule. I'll pass any info I receive on to you so that we can clear up this mystery.

Thanks again for helping.
Layne

[Martin Vorlaender]

Volker,

>>>
I must admit, that I still have not fully understood, where the real source of the timezone rule definition is located.
<<<

The FAQ has a complete chapter about VMS system time, time keeping, daylight savings, etc.

See http://h71000.www7.hp.com/wizard/faq/vmsfaq_004.html#time4 for explanations about timezones.

cu,
Martin

[Robert_Boyd]

I've worked with situations where we had systems running NTP, DTSS, both and neither all in the same environment. Since there were so many systems, I wrote a command procedure that works correctly up through VMS V7.3-2 in all the cases I've dealt with so far.

This assumes that you've already executed the proper timezone setup procedure as relates the the system you're on.

Here is the command procedure as an attachment.
I'd be curious to see any feedback about how it is affected by changes in V8.x

Robert Boyd

[Jan van den Ende]

Layne,


From your Forum Profile:


I have assigned points to 12 of 34 responses to my questions.


Maybe you can find some time to do some assigning?

Mind, I do NOT say you necessarily need to give lots of points. It is fully up to _YOU_ to decide how many. If you consider an answer is not deserving any points, you can also assign 0 ( = zero ) points, and then that answer will no longer be counted as unassigned.
Consider, that every poster took at least the trouble of posting for you!

To easily find your streams with unassigned points, click your own name somewhere.
This will bring up your profile.
Near the bottom of that page, under the caption â My Question(s)â you will find â questions or topics with unassigned points â Clicking that will give all, and only, your questions that still have unassigned postings.

Thanks on behalf of your Forum colleagues.

PS. â nothing personal in this. I try to post it to everyone with this kind of assignment ratio in this forum. If you have received a posting like this before â please do not take offence â none is intended!

Proost.

[Layne Burleson_1]

After the TDF V5 patch on VMS 7.3-1 you must run the sys$manager:utc$time_setup.com.