Timezones and TDF/daylight savings

[Fredrik.eriksson]

Hi, This might be a silly question but I can't seem to find any good way to list which is the current Timezone/TDF setting and also anyway to detect if daylight savings is in proper use.

Is there some easy way to do this or do i have to runt SYS$MANAGER:UTC$TIME_SETUP.COM?

Best regards
Fredrik Eriksson

[Oswald Knoppers_1]

I always look at the logicals *zone*:

"SYS$TIMEZONE_DAYLIGHT_SAVING" = "1"
"SYS$TIMEZONE_DIFFERENTIAL" = "7200"
"SYS$TIMEZONE_NAME" = "MEST"
"SYS$TIMEZONE_RULE" = "MET-1MEST-2,M3.5.0/02,M10.4.0/03"

And the value of the sysgen parameter auto_dlight_sav.

This parameter should be set on 1 (unless you use the DTSS component of DECnet-Plus for changing the time.

Regards,

Oswald

[Fredrik.eriksson]

Thanks for the quick reply.

And since I have another question regarding this same subject I'll reuse this :)

I use NTPD to set the time on my OpenVMS 7.3-2 machines. Does the NTPD work with standard time and OpenVMS adds the +X/-X timezone? Or is it NTPD that sets the timezone options?

Quite worried since the machines didn't do it properly when it switched to summer time this year.

Best regards

[Joseph Huber_1 · Accepted solution]

And all together in one command:

@SYS$MANAGER:UTC$TIME_SETUP.COM SHOW

[Joseph Huber_1]

NTP operates on UTC, but uses the SYS$TIMEZONE_DIFFERENTIAL logical to adjust the local VMS time.

So the UTC$TIME_SETUP has to be correct, and the system parameter auto_dlight_sav must be set to make the DST change happen.

[Fredrik.eriksson]

Okey, so basically I need to set the sysgen parameter auto_dlight_save to 1 and it should all be alright?

So steps needed:
1) $ sysgen set auto_dlight_save 1
2) and then a batchjob 26-OCT-2008 03:05:00 that does:
$ @DSA0:[VMS$COMMON.SYSMGR]TCPIP$NTP_SHUTDOWN.COM
$ @DSA0:[VMS$COMMON.SYSMGR]TCPIP$NTP_STARTUP.COM

Then all should be nice 'n dandy? And the only issue is that it won't sync the time properly after DST change between 02.00 and 03.05?

Or is there another way of doing this that's more proper? I've seen something about using "set_vms_logicals" in the ntp configuration files but only seems to bring up pages on google concerning multinet NTP. Is there a differance in NTP clients between multinet ntp and decnet-plus ntp?

Best regards
Fredrik Eriksson

[Brad McCusker]

A couple comments -

You didn't specify the VMS version. That makes a difference with respect to AUTO_DLIGHT_SAV parameter. It's only available on Alpha 7.3 and later and Integrity.

Changing AUTO_DLIGHT_SAV requires a reboot. Don't forget to work that into your plan before the 26th.

Brad McCusker
Software Concepts International
www.sciinc.com

[Brad McCusker]

Whoops - I just saw that you specified the version in a later reply. OK. So don't forget the reboot to set AUTO_DLIGHT_SAV.

[Fredrik.eriksson]

Well there's an issue in rebooting the systems... I can't reboot them before this weekend. Our policy says I need to announce it 2 weeks before, and I was silly enough to remembering that this might become an issue this morning ;P

So then my options are to set the SYS$TIMEZONE_DIFFERENTIAL logical to 3600 instead of the current 7200 and then sort out my auto_dlight_save for the next DST change?

Or can I use the set_vms_logicals option in ntp config?

Best regards
Fredrik Eriksson

[Fredrik.eriksson]

Should have mentioned in my above post that I'm not using TCPWare or Multinet. It's "old fashioned" HP TCP/IP V5.4. Seems to matter atleast when I google since I can't seem to find any information about NTP and automagically changing DST from it.

Best regards
Fredrik Eriksson