Not if you properly use a kernel tool to sync time with the host. I use a beefy laptop with multiple nic's which allows me to run a couple of vm's on top of it. Traveling sipx and firewall for demo.
In my case my firewall is dhcp and options are all there. The firewall is also an ntp server. As a demo unit with only a few phones on it, it never has issues. Its all in the secret sauce... ============================ Tony Graziano, Manager Telephone: 434.984.8430 Fax: 434.984.8431 Email: [email protected] LAN/Telephony/Security and Control Systems Helpdesk: Telephone: 434.984.8426 Fax: 434.984.8427 Helpdesk Contract Customers: http://www.myitdepartment.net/gethelp/ ----- Original Message ----- From: [email protected] <[email protected]> To: sipx-users <[email protected]> Sent: Thu Sep 02 16:04:19 2010 Subject: Re: [sipx-users] NTP server - or lack of On Thu, Sep 2, 2010 at 2:10 PM, Worley, Dale R (Dale) <[email protected]> wrote: > ________________________________________ > From: [email protected] > [[email protected]] On Behalf Of Todd Hodgen > [[email protected]] > > I’m wanting to run a sipXecs system without internet access, or access to > an external NTP server for Demonstration purposes. Does anyone know a > way to work around the need for an NTP server, and keep the time from > flashing on end devices. Without an NTP server, the boot process for > Polycom phones is delayed as they look for NTP source, and when they come > up, the clock flashes on them annoyingly. > _________________________________________ > > Set up an NTP server on some computer within the LAN, probably sipX. > Configure it to "synchronize to the local clock" if it cannot access an > authoritative server. This involves something like the following lines in > /etc/ntpd.conf: > > # Undisciplined Local Clock. This is a fake driver intended for backup > # and when no outside source of synchronized time is available. > server 127.127.1.0 # local clock > fudge 127.127.1.0 stratum 10 > > Use this NTP server as you otherwise would -- everything will sync to it. > > One problem with "local clock" use is that the frequency of local clocks > is not very accurate, although their frequency tends to be very > consistent. So your time will drift away from real time by as much as a > minute a day. The way to get around that is to have the NTP server > calculate the rate of drift and compensate for it. Add this to ntpd.conf: > > driftfile /var/lib/ntp/drift > > Then connect the system to the Internet and tell NTP about an > authoritative server. In that configuration, NTP will calcuate and save > the difference between the local clock frequency and real time, and save > the value in the "drift file". Then when you boot the system disconnected > from the Internet, NTP will tweak the local clock to run very close to > true frequency. Of course, you can't set the time from your watch better > than a minute from real time, but at least the computer's clock won't > drift off. > > Dale > _______________________________________________ > sipx-users mailing list > [email protected] > List Archive: http://list.sipfoundry.org/archive/sipx-users/ > Time sync or accurate time I should say, will get even uglier if your running this in VM's Matt P. _______________________________________________ sipx-users mailing list [email protected] List Archive: http://list.sipfoundry.org/archive/sipx-users/ _______________________________________________ sipx-users mailing list [email protected] List Archive: http://list.sipfoundry.org/archive/sipx-users/
