Operating System - OpenVMS
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NTP Client and TCPIP 5.6

Brent Weaver_1
Occasional Advisor

NTP Client and TCPIP 5.6

Hello. I need to add NTP servers to a VMS cluster running TCPIP 5.6 VMS 8.3. My questions are this:

1 - AUTO_DLIGHT_SAV is set to 1, is this OK and will NTP conflict?

2 - Does NTP change both VMS system time as well as UTC (i.e. TDF offest)?

3 - What other precautions should I be aware of?

Any advice is more than welcome! Thanks!
Volker Halle
Honored Contributor

Re: NTP Client and TCPIP 5.6


NTP is NOT involved in DST changes, it just synchronizes the time via UTC time from the NTP servers configured. OpenVMS itself is taking care of the DST time change with AUTO_DLIGHT_SAV=1 and timezone update, TDF etc.

Consider to configure more than 1 NTP server.


Andy Bustamante
Honored Contributor

Re: NTP Client and TCPIP 5.6

Load the latest patches for Daylight savings time and TCPIP. Especially before Sept 18.

For a cluster, I would configure a local system as a time source, higher statum than other sources. In the event external connetivity is lost, you'll fail back to this system.

If you don't have time to do it right, when will you have time to do it over? Reach me at first_name + "." + last_name at sysmanager net