As I recall it, all time references in a sysplex must be within a certain tolerance and this is ensured by requiring them to be connected to a single time source (ETR ID), not 2 sources that are equal within a certain tolerance.
Kees. -----Original Message----- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf Of Staller, Allan Sent: Friday, February 07, 2014 15:03 To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: Sysplex Common Time Source ISTR that all time references in a SYSPLEX must be within a certain tolerance (I have no recollection of the actual value). If the local time source exceeded this tolerance, the ETR (STP/9037) would guide them to the same value, or failing that , remove the system from the plex. The act of syncing the STP and the 9037 to the same time ETR might/might not provide sufficient accuracy. HTH, <snip> >That was what we originally though too, but our local IBM support >person told us we couldn't. Thinking further about configuration >activities to migrate to mixed CTN mode, I'm not seeing how on the non >STP capable processor we're going to be able to set the name of the >mixed CTN, since it isn't going to have the STP tab for that CEC, I'm not sure that that matters. IIRC, the requirement is that all systems in the sysplex get their time from the same source. As long as the z10 gets it from the timers, and there's another CEC in the CTN getting it from the same timers and acting as the primary time server for the CTN, I believe that would work. z10 <- timer zEC12 <- timer | Primary time server \/ STP other STP CECs Before STP, there was no STP tab on the HMC and the CECs were able to participate in the sysplex by virtue of using the same timer. I *think* the migration would be to make the time source the timer connected to one zEC12, make that the PTS, then add the z10 pointing to the timer. But I haven't read the fine manuals for some time, and it seems like the PTS becomes a sinle point of failure, unless at least one other machine in the CTS has a timer connection too. The point about the mixed mode CTN being envisioned as a fall-back situation, not an expected long-term situation is also good one. And if IBM is telling you "no", it's hard to argue that you'd want to try to do it. Scott </snip> ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN ******************************************************** For information, services and offers, please visit our web site: http://www.klm.com. This e-mail and any attachment may contain confidential and privileged material intended for the addressee only. If you are not the addressee, you are notified that no part of the e-mail or any attachment may be disclosed, copied or distributed, and that any other action related to this e-mail or attachment is strictly prohibited, and may be unlawful. If you have received this e-mail by error, please notify the sender immediately by return e-mail, and delete this message. Koninklijke Luchtvaart Maatschappij NV (KLM), its subsidiaries and/or its employees shall not be liable for the incorrect or incomplete transmission of this e-mail or any attachments, nor responsible for any delay in receipt. Koninklijke Luchtvaart Maatschappij N.V. (also known as KLM Royal Dutch Airlines) is registered in Amstelveen, The Netherlands, with registered number 33014286 ******************************************************** ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
