Zabbix server, agents, and potentially proxy binaries have to be updated. The exact process will depend on how you installed them in the first place. Compiled from the source? Perform the same steps as during the installation. Installed from packages? Use the distribution package management tools to perform the upgrade. This process should be fairly simple, and we discussed the details back in Chapter 1, Getting Started with Zabbix.

After starting the upgraded Zabbix server, in some rare cases you might see a log entry like this:

10852:20151231:094918.820 starting automatic database upgrade 

For a minor version upgrade, that could be a change to the database indexes to improve performance, but we'll discuss that in more detail when we get to the major version upgrades.