Hello, Have you or are you using the tickless kernel with this setup, and does that make a difference? wilson -----Original Message----- From: redhat-list-bounces@xxxxxxxxxx [mailto:redhat-list-bounces@xxxxxxxxxx] On Behalf Of Ryan Golhar Sent: Thursday, January 22, 2009 2:45 PM To: General Red Hat Linux discussion list Subject: Re: xen vm not keeping date/time properly George Magklaras wrote: > > > Ryan Golhar wrote: >> 9.2.2.2 says xen just passed the time-related calls to Dom0, but that >> can't be the case because the times are different. >> > That is because if you do run ntpd inside the VM, this can create the > problem. > >> noselect? inside the VM? >> > Yes on the guest system, and run ntpd normally on the Dom0. > I'm running ntpd normally on the host, and ntpd inside the VM using the noselect parameter on the server line, such as: server siriusc.umdnj.edu noselect server 0.rhel.pool.ntp.org noselect server 1.rhel.pool.ntp.org noselect server 2.rhel.pool.ntp.org noselect After about a half hour after restarting the ntpd server inside the guest, I'm noticing clock skew of about 30 seconds. I'm sure this will continue to grow. Anyone have any other ideas? I'm surprised there isn't a solution to this. This is a huge problem, especially for an enterprise system that relies on the date/time being correct. Ryan >> We are running on a Sun SunFire X4150. > What I stated was on a Dell 2950 PowerEdge, but I shall get hold of a > SunFire and repeat the test, see if I get the same issue. It does state > that there might be some kernel parameters that need tweaking, but, I am > curious to find out what's going on, as we will be using SunFire kit > with Xen soon. > > GM > >> >> George Magklaras wrote: >>> This page might offer some help: >>> >>> >>> http://support.ntp.org/bin/view/Support/KnownOsIssues#Section_9.2.2. >>> >>> To recap, we use the 'noselect' keyword to avoid the running ntpd on >>> the client to attempt to sync with the defined servers and ntpq does >>> not report any disturbing drifts on the client...and we do run ntpd >>> normally (no 'noselect') on Dom0. >>> >>> What happens (happened if you have already tried) if you try and do >>> this? And what's your hardware platform? >>> >>> GM >>> > Notice: This e-mail message, together with any attachments, contains information of Merck & Co., Inc. (One Merck Drive, Whitehouse Station, New Jersey, USA 08889), and/or its affiliates (which may be known outside the United States as Merck Frosst, Merck Sharp & Dohme or MSD and in Japan, as Banyu - direct contact information for affiliates is available at http://www.merck.com/contact/contacts.html) that may be confidential, proprietary copyrighted and/or legally privileged. It is intended solely for the use of the individual or entity named on this message. If you are not the intended recipient, and have received this message in error, please notify us immediately by reply e-mail and then delete it from your system. -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list
