That makes that CP will display a good time, but it will not help the guests: guests get their time by using the STCK instruction and apply their timezone setting. Exceptions:
- VSE running with TIMEZONE VM. But, I doubt it will use the changed time without an IPL - Some parts of CMS use CP's time, other parts also use STCK And, if this VM system is connected to other VM systems and one uses SENDFILE to exchange files, strange things will happen to the file's timestamps. The reason is that when the files are sent to the VM spool, their timetamp is changed to UTC. On the receiving system, the UTC timestamp is converted to local time. Now you'd have a whole number of hours as difference between the sent and received file. After such a change you'd have whole hours +/- 4 minutes. At my former customer's installation (where we had up to 20 VM systems, in many timezones, only CMS), an operator wanted to be clever and changed the timezone to correct the clocks without asking me. The result for the file's timestamp was not fine at all. The timezone was quickly reset. 2011/7/28 Wandschneider, Scott <scott.wandschnei...@wipro.com> > We have a host VM system (z/VM 5.4 0902) that is located on the east coast > of the USA with a time zone of "WEST 04.00.00" however the actual TOD clock > is behind by four (4) minutes. Scheduling an IPL is difficult as this system > hosts many clients. To adjust the TOD clock, without an IPL, it has been > suggested that I issue the following two commands, which appears to have > worked on a second level 2.4 VM/ESA system. Comments and suggestions from > this group would be appreciated. > > DEFINE TIMEZONE EDT WEST 03.56.00 > SET TIMEZONE EDT > > Thank you, > Scott R Wandschneider > Systems Programmer 3|| Technology Infrastructure Services, Wipro || 11707 > Miracle Hills Drive, Omaha, NE, 68154-4457|| : 402.963.8905 || > :847.849.7223 || : scott.wandschnei...@wipro.com **Think Green - > Please print responsibly** > > > Confidentiality Note: This e-mail, including any attachment to it, may > contain material that is confidential, proprietary, privileged and/or > "Protected Health Information," within the meaning of the regulations under > the Health Insurance Portability & Accountability Act as amended. If it is > not clear that you are the intended recipient, you are hereby notified that > you have received this transmittal in error, and any review, dissemination, > distribution or copying of this e-mail, including any attachment to it, is > strictly prohibited. If you have received this e-mail in error, please > immediately return it to the sender and delete it from your system. Thank > you. > -- Kris Buelens, IBM Belgium, VM customer support
