The only use case I'm aware of where standard NTP usage is not accurate enough, but asking for ETR or STP usage is when you want Linux to participate in an XRC asynchronous replication scheme *and* you have a requirement for building XRC time consistency groups across multiple OS images. Those might either be homogeneous Linux or heterogenous Linux and z/OS environments where the z/OS data mover replicates data based on TOD timestamps and you can't tolerate time inconsistency in case of an outage.
Best regards, Ingo -- Ingo Adlung, STSM, System z Linux and Virtualization Architecture mail: [EMAIL PROTECTED] - phone: +49-7031-16-4263 Linux on 390 Port <LINUX-390@VM.MARIST.EDU> wrote on 11.10.2006 17:40:42: > > -----Original Message----- > > From: Linux on 390 Port [mailto:[EMAIL PROTECTED] On > > Behalf Of Dave Jones > > Sent: Wednesday, October 11, 2006 10:31 AM > > To: LINUX-390@VM.MARIST.EDU > > Subject: Re: Server Time Protocol support for zSeries > > > > > > That's a good question, John. As far as I know, Linux on > > zSeries (either > > VM guest or native) can use an external time source to set its clock. > > > > The real problem is that z/VM and it's guests can not use the > > same time > > source as z/OS to sync their clocks together. Consider the case where > > there are two LPARS in a z9-BC, one running z/OS and using STP to set > > its clock and the other LPAR running z/VM and Linux guests > > with its time > > set by the operator's Timex. :-) > > > > DJ > > I'm still a bit confused. I know that z/VM cannot set its clock to the > STP time source. But why couldn't the Linux systems under z/VM use XNTP > to set their clock to the z/OS value? z/OS 1.7 can run an NTP daemon > which the Linux instances should be able to use. I hope that would be > "close enough". > > -- > John McKown > Senior Systems Programmer > HealthMarkets > Keeping the Promise of Affordable Coverage > Administrative Services Group > Information Technology > > This message (including any attachments) contains confidential > information intended for a specific individual and purpose, and its > content is protected by law. If you are not the intended recipient, you > should delete this message and are hereby notified that any disclosure, > copying, or distribution of this transmission, or taking any action > based on it, is strictly prohibited. > > > ---------------------------------------------------------------------- > For LINUX-390 subscribe / signoff / archive access instructions, > send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit > http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
