To clarify… I’m of the strong opinion that using VMs as NTP servers is a bad idea. My supervisor is electing to disregard the overwhelming documentation that it’s a bad idea. He’s also disregarding his own lack of qualification for evaluating the issues at hand. He said, “Well, try it and see if it works.” So far, I’ve been unable to demonstrate any results that show him beyond a doubt that it won’t work out well.
Based on earlier feedback from this group, I’ve sent him a potential workaround of sticking an NTP server VM on each of four or more physical VM hosts. The idea is that if one or two physical hosts get busy, the NTP clients will be able to disregard the one or two NTP server VMs that are drifting. The obvious problem is that if a physical host fails and all remaining physical hosts get swamped at the same time, chaos will result as all of the NTP server VMs drift randomly at the same time. I also said I would only proceed if he provides a written acknowledgement that he’s directing me to implement a system that I am recommending against. :-) JC From: brian.mat...@betteradmin.com [mailto:brian.mat...@betteradmin.com] On Behalf Of Brian Mathis Sent: Monday, April 4, 2016 2:29 PM To: Jeremy Charles <jchar...@epic.com> Cc: tech@lists.lopsa.org Subject: Re: [lopsa-tech] VM as an NTP server Time syncing is one of the biggest problems VMs have. Unless you're able to fully understand the NTP source code and and all of the intricacies of clock syncing, you really aren't qualified to evaluate it. "I don't see any issues", especially in the face of pretty much every Internet resource telling you no to do it, doesn't cut it. As others have said, many other hardware devices in your environment might be able to provide the service, such as routers, switches, firewalls, etc... You're much better off looking into something like that than just crossing your fingers and ignoring the generally well-accepted advice of others. ~ Brian Mathis @orev On Mon, Apr 4, 2016 at 12:18 PM, Jeremy Charles <jchar...@epic.com<mailto:jchar...@epic.com>> wrote: I’m seeing all sort of documentation about how it’s not a great idea to use a VM as an NTP server due to how sketchy time tracking is within a VM. My supervisor directed me to try it anyway. He feels that our existing NTP servers are too old and need to be replaced, and he wants to replace them with VMs rather than physical servers. I’m not seeing any difference in behavior between the two existing physical NTP servers and the VM that I set up to test as an NTP server. Thoughts? == Jeremy Charles Epic’s Computer and Technology Services Division jchar...@epic.com<mailto:jchar...@epic.com> 608-271-9000<tel:608-271-9000> _______________________________________________ Tech mailing list Tech@lists.lopsa.org<mailto:Tech@lists.lopsa.org> https://lists.lopsa.org/cgi-bin/mailman/listinfo/tech This list provided by the League of Professional System Administrators http://lopsa.org/
_______________________________________________ Tech mailing list Tech@lists.lopsa.org https://lists.lopsa.org/cgi-bin/mailman/listinfo/tech This list provided by the League of Professional System Administrators http://lopsa.org/
