I'd say Cluster setting. We should let users pick if they want to use hypervisor tools based sync or local/external NTP servers.
I'm all for local/external NTP servers, as I know how those never gave me issues in past (especially when you go through hypervisors upgrades and vm tools upgrades). > -----Original Message----- > From: John Burwell [mailto:jburw...@basho.com] > Sent: Thursday, May 30, 2013 1:02 PM > To: dev@cloudstack.apache.org > Subject: Re: [DISCUSS] How to best do time sync. (WAS: [VOTE] Release > Apache CloudStack 4.1.0 (fifth round)) > > Ilya, > > One very important note is that NTP is only used for Xen. For KVM and > VMWare, time sync is accomplished through kernel drivers/system daemons > with NTP configured in the hypervisor configuration. Therefore, this model > would need to be conditional based on the hypervisor type -- possibly a > cluster-level setting? > > Thanks, > -John > > On May 30, 2013, at 12:58 PM, "Musayev, Ilya" <imusa...@webmd.net> > wrote: > > > Thanks Chip. > > > > I've posted this response under CLOUDSTACK-2492.. curious what others > may think about a long term solution to this problem.. > > > > -------------- > > I think we should make the whole NTP schema more modular and robust. > > > > For example, in my experience working for several companies, not even > > once have we used vmware tools time sync - due to known bugs and > > issues. Instead we would prefer to use local NTP server or external > > pool.ntp.org > > > > There are two way we can address this: > > > > Quick solution (quick means not ideal): > > Capture the NTP servers defined on MS and feed it as arguments to > > system vms On initial start of the system vm, check if you can access > > ntp servers defined on MS vm, if not, check if you can access > > pool.ntp.org servers - if none defined - use hypervisor tools sync > > > > Long term solution: > > When adding zones, define NTP servers in UI to be used with system VMs > or bypass NTP servers and allow vm-tools time sync with hypervisor. > > > > Thoughts? > > > > Thanks > > ilya > > > >> -----Original Message----- > >> From: Chip Childers [mailto:chip.child...@sungard.com] > >> Sent: Wednesday, May 29, 2013 2:30 PM > >> To: dev@cloudstack.apache.org > >> Subject: [DISCUSS] How to best do time sync. (WAS: [VOTE] Release > >> Apache CloudStack 4.1.0 (fifth round)) > >> > >> Ilya, > >> > >> I'm breaking off a new thread for this discussion. If you want to > >> discuss the design options presented in the jira, this would be a > >> good thread for that. ;-) > >> > >> -chip > >> > >> On Wed, May 29, 2013 at 06:24:27PM +0000, Musayev, Ilya wrote: > >>> John, > >>> > >>> I clearly see your concern, please review my response under > >>> CLOUDSTACK- > >> 2492. > >>> > >>> Thanks > >>> ilya > >>> > >>>> -----Original Message----- > >>>> From: John Burwell [mailto:jburw...@basho.com] > >>>> Sent: Wednesday, May 29, 2013 10:10 AM > >>>> To: dev@cloudstack.apache.org > >>>> Subject: Re: [VOTE] Release Apache CloudStack 4.1.0 (fifth round) > >>>> > >>>> -0. I don't believe we should be shipping a release with known > >>>> clock sync issues (see CLOUDSTACK- > >>>> 2492<https://issues.apache.org/jira/browse/CLOUDSTACK-2492>). > >>>> Since the community voted to go forward, I will not cast a -1. > >>>> However, I feel it is important to highlight operational issues > >>>> that, in my view, a system such as CloudStack should never > >>>> knowingly > >> ship. > >>>> > >>>> -John > > > > >
