Solving Linux Time Drift

Time drift is a major issue with Linux systems running under virtualisation platforms. To fix this issue follow instructions.

Time drift is a major issue with Linux systems running under virtualisation platforms. Using ntpdate to update your clock regularly and then hwclock to sync it is the general method. However, this can cause sudden time changes by a few seconds which causes services such as Dovecot to restart.

To fix this issue you can change the clock source in your grub.conf. With CentOS or Redhat based Linux Operating Systems:

• Edit the files at /etc/grub.conf & /boot/grub/grub.conf
• Change the kernel lines by adding clock=pit to the end of them:
• For example:
  kernel /vmlinuz-2.6.18-164.el5 ro root=/dev/VolGroup00/LogVol00 clock=pit
• Restart your VPS

Generally CentOS will then keep time. However, if you have issues please see the article below (generally for Ubuntu) section 2 (install NTPD service) with configuration.

With Ubuntu

• See: https://www.vpsblocks.com.au/support/Knowledgebase/Article/View/304/0/ubuntu-time-drift

If you are not sure how to do this, we can do this for you at a scheduled time, just contact us at support@vpsblocks.com.au

Note that all new templates have these changes integrated into them.