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Configuring a NTP Client on a Virtual Machine
<html><p style=“margin:0em; padding:0em;”>Again, you need to edit /etc/ntp.conf using the editor of your choice to tailor things to your needs.</p></html>
sudo vim /etc/ntp.conf<html><p style=“margin:0em; padding:0em;”>The ntp.conf file on our client is as follows:</p></html>
# /etc/ntp.conf # Disable the panic threshold to allow irregular clock offsets tinker panic 0 # Local clock oscillation file driftfile /var/lib/ntp/ntp.drift # Allow statistics to be logged. statsdir /var/log/ntpstats/ # Logging configuration statistics loopstats peerstats clockstats filegen loopstats file loopstats type day enable filegen peerstats file peerstats type day enable filegen clockstats file clockstats type day enable # Access control configuration restrict default kod nomodify notrap nopeer noquery # Deny everybody by default restrict 127.0.0.1 # Allow unrestricted access to self # NTP servers to syncronise with server vmserver03.student.lab
<html><p style=“margin:0em; padding:0em;”> The main difference between our client and our server ntp.conf files is that the client file does not have a restrict directive that allows it to serve time to other systems. It also does not look to itself as a server.<br /> We need to do some additional configuration before we restart the NTP service to apply the changes on our virtual macines.</p></html>
Special Settings for Virtual Machines
<html><p style=“margin:0em; padding:0em;”>Because the NTP clients for the purposes of this portfolio will be used on Xen Virtual Machines, a few special configuration enhancements need to be made. The first, is the line tinker panic 0 from our client version of the ntp.conf. This allows the NTP client to update from the NTP server, regardless of differences in current system time – there are instances where the VM will begin adjusting it's clock automatically due to various system errors. The other requirement is to create a step-tinkers file and place it in /etc/ntp directory. (You may need to create this directory as it is not created by default as part of the installation process for NTP.)</p></html>
sudo sh -c "mkdir /etc/ntp && vim /etc/ntp/step-tinkers"
# /etc/ntp/step-tinkers
vmserver03.student.lab
<html><p style=“margin:0em; padding:0em;”>Restart the NTP service to implement the changes.</p></html>
sudo /etc/init.d/ntp restart
