Server Monitoring with Zabbix

You can find several startup script examples within the zabbix-1.8.1/misc/init.d directory. Copy the one for your installation to /etc/init.d, and make any necessary changes. For Ubuntu, I used the scripts located in the debian directory. In both the server and agent configuration files, I needed to change the location of the binary from /home/zabbix/bin to /usr/local/sbin.

The zabbix-1.8.1/frontends/php directory contains the Web-based front end to Zabbix. Copy this directory structure somewhere below Apache's DocumentRoot, and load that URL in your Web browser. You will be greeted with the Zabbix Introduction screen (Figure 1). This wizard-like page steps through your configuration and presents you with a License Agreement. The next screen details any configuration changes that need to be made before continuing, such as PHP memory and execution time settings.

Figure 1. Zabbix Introduction Screen

Once past the configuration screen, the main login screen loads. The default account is Admin with the password zabbix. Of course, once you're logged in, change the default password. The front-end layout consists of two rows of options (Figure 2). Click Administration, then Users. Make sure the pull-down menu located on the right side of the screen has Users selected instead of User Groups. Next, click on the admin user. A configuration page for the Admin user is shown (Figure 3). First, change the password. Also, add an e-mail address (click Add next to the Media line), as we're going to configure alerts to be sent via e-mail later in this article.

Figure 2. Front-End Options

Figure 3. Admin User Configuration Page

Three files need to be copied to a new client: the zabbix_agentd client binary to /usr/sbin, the zabbix_agentd.conf configuration file to /etc/zabbix and an init script. Edit the zabbix_agentd.conf configuration file, and change the line that reads Server= to equal the Zabbix server name, and change the Hostname= line to equal the client hostname. Once completed, start up the zabbix agent with the init script.

Back on the Zabbix server Web page, click Configuration→Hosts within the Web front end. Make sure Hosts is selected in the pull-down menu on the right-hand side of your screen, and then click the Create Host button. The Hosts configuration screen appears (Figure 4). You can give your host any name you choose, but I recommend staying with the short hostname (hostname -s) instead of a fully qualified domain if you can. Add it into the Linux servers group, and populate the DNS name with the fully qualified DNS name. I could choose to monitor this host with its IP address, but I'll trust that DNS always will be up to date. The only other change to this page is to click Add under the Linked templates area. Click the radio button next to Template_Linux and choose Select at the bottom of this pop-up window. Back at the Host screen, click Save. All the monitoring Items and Triggers included in the Template_Linux will be added to the client.

Figure 4. Host Configuration Screen

The Zabbix monitoring structure starts with Items (checks or collects data), then Triggers (monitors data in Items) and finally, Actions (e-mail, SMS or run scripts).

Items can be considered the “data collectors”. Some items are built in to the agent binary, and others will be custom scripts. After installing Zabbix, you will have a range of templates that contain these Items for common operating systems checks, such as Linux, Solaris, MAC OS X and Windows systems.

Let's look at the template we used with our first client. Using the Global search box at the upper right-hand side, search for “Template_Linux”. The search results should return a page that has links to the Items, Triggers or Graphs for this template (Figure 5). Select the Items link. All these Items will be monitored on any host that has the Template_Linux template applied to it, such as the first host configured above.

Figure 5. Template_Linux

Click the Item called Free disk space on /. Here are all the details for this Item (Figure 6). Most fields are self-explanatory, but here are few important ones:

Figure 6. Free disk space on / Item

You also can tell Zabbix what type of data is going to be returned: text, characters or numbers and a multiplier for that value. Also, you can specify for how long you want fine-grained graphs (history) and trends. The Applications section is where you can group similar checks. For example, if you were adding another filesystem item, you would add it to the Filesystem application.