timezone

Make sure your Linux servers' date and time are correct and synchronized

Nowadays, most people assume that all modern computers and operating systems have network time synchronization set up properly and switched on by default. However, this is not the case with many Linux servers—especially if you didn't install Linux and configure it yourself (as would be the case with most cloud-based OS images like those used to generate new servers on Linode).

After setting up a new server on Linode or some other Linux VPS or dedicated server provider, you should always do the following to make sure the server's timezone and date and time synchronization are configured and working correctly:

Drupal 6.x and PHP 5.3.x - Date Timezone warnings

This morning, I was presented with quite the conundrum: one of my servers suddently started having about 4x the normal MySQL traffic it would have in a morning, and I had no indication as to why this was happening; traffic to the sites on the server was steady (no spikes), and I couldn't find any problems with any of the sites.

munin mysql traffic spike

However, after inspecting the Apache (httpd) error logs for the Drupal 6 sites, I found a ton of PHP warnings on almost all the sites. Something like the following: