2 Requirements

Hardware

Memory

Zabbix requires both physical and disk memory. 128 MB of physical memory and 256 MB of free disk space could be a good starting point. However, the amount of required disk memory obviously depends on the number of hosts and parameters that are being monitored. If you're planning to keep a long history of monitored parameters, you should be thinking of at least a couple of gigabytes to have enough space to store the history in the database. Each Zabbix daemon process requires several connections to a database server. Amount of memory allocated for the connection depends on configuration of the database engine.

CPU

Zabbix and especially Zabbix database may require significant CPU resources depending on number of monitored parameters and chosen database engine.

Other hardware

A serial communication port and a serial GSM modem are required for using SMS notification support in Zabbix. USB-to-serial converter will also work.

Examples of hardware configuration

The table provides several examples of hardware configurations:

Supported platforms

Due to security requirements and mission-critical nature of monitoring server, UNIX is the only operating system that can consistently deliver the necessary performance, fault tolerance and resilience. Zabbix operates on market leading versions.

Zabbix is tested on the following platforms:

• Linux
• IBM AIX
• FreeBSD
• NetBSD
• OpenBSD
• HP-UX
• Mac OS X
• Solaris
• Windows: all desktop and server versions since XP (Zabbix agent only)

Software

Zabbix is built around a modern Apache web server, leading database engines, and PHP scripting language.

Database management system

Frontend

The following software is required to run Zabbix frontend:

Web browser on client side

Cookies and Java Script must be enabled.

Latest versions of Google Chrome, Mozilla Firefox, Microsoft Internet Explorer and Opera are supported. Other browsers (Apple Safari, Konqueror) may work with Zabbix as well.

Server

Mandatory requirements are needed always. Optional requirements are needed for the support of the specific function.

Java gateway

If you obtained Zabbix from the source repository or an archive, then the necessary dependencies are already included in the source tree.

If you obtained Zabbix from your distribution's package, then the necessary dependencies are already provided by the packaging system.

In both cases above, the software is ready to be used and no additional downloads are necessary.

If, however, you wish to provide your versions of these dependencies (for instance, if you are preparing a package for some Linux distribution), below is the list of library versions that Java gateway is known to work with. Zabbix may work with other versions of these libraries, too.

The following table lists JAR files that are currently bundled with Java gateway in the original code:

Java gateway compiles and runs with Java 1.6 and above. It is recommended that those who provide a precompiled version of the gateway for others use Java 1.6 for compilation, so that it runs on all versions of Java up to the latest one.

Database size

Zabbix configuration data require a fixed amount of disk space and do not grow much.

Zabbix database size mainly depends on these variables, which define the amount of stored historical data:

• Number of processed values per second

This is the average number of new values Zabbix server receives every second. For example, if we have 3000 items for monitoring with refresh rate of 60 seconds, the number of values per second is calculated as 3000/60 = 50.

It means that 50 new values are added to Zabbix database every second.

• Housekeeper settings for history

Zabbix keeps values for a fixed period of time, normally several weeks or months. Each new value requires a certain amount of disk space for data and index.

So, if we would like to keep 30 days of history and we receive 50 values per second, total number of values will be around (30*24*3600)* 50 = 129.600.000, or about 130M of values.

Depending on the database engine used, type of received values (floats, integers, strings, log files, etc), the disk space for keeping a single value may vary from 40 bytes to hundreds of bytes. Normally it is around 90 bytes per value for numeric items². In our case, it means that 130M of values will require 130M * 90 bytes = 10.9GB of disk space.

• Housekeeper setting for trends

Zabbix keeps a 1-hour max/min/avg/count set of values for each item in the table trends. The data is used for trending and long period graphs. The one hour period can not be customised.

Zabbix database, depending on database type, requires about 90 bytes per each total. Suppose we would like to keep trend data for 5 years. Values for 3000 items will require 3000*24*365* 90 = 2.2GB per year, or 11GB for 5 years.

• Housekeeper settings for events

Each Zabbix event requires approximately 250 bytes of disk space¹. It is hard to estimate the number of events generated by Zabbix daily. In the worst case scenario, we may assume that Zabbix generates one event per second.

For each recovered event an event_recovery record is created. Normally most of events will be recovered so we can assume one event_recovery record per event. That means additional 80 bytes per event.

Optionally events can have tags, each tag record requiring approximately 100 bytes of disk space¹. The number of tags per event (#tags) depends on configuration. So each will need an additional #tags * 100 bytes of disk space.

It means that if we want to keep 3 years of events, this would require 3*365*24*3600* (250+80+#tags*100) = ~30GB+#tags*100B disk space².

The table contains formulas that can be used to calculate the disk space required for Zabbix system:

So, the total required disk space can be calculated as:
Configuration + History + Trends + Events
The disk space will NOT be used immediately after Zabbix installation. Database size will grow then it will stop growing at some point, which depends on housekeeper settings.

Default port numbers

The following table lists default port numbers that Zabbix components listen on:

Time synchronisation

It is very important to have precise system date on server with Zabbix running. ntpd is the most popular daemon that synchronizes the host's time with the time of other machines. It's strongly recommended to maintain synchronised system date on all systems Zabbix components are running on.

If the time is not synchronised Zabbix will convert timestamps of the gathered data into Zabbix server time by taking client/server timestamps after establishing data connection and adjusting the received item value timestamps by the client-server time difference. To keep it simple and avoid possible complications the connection latency is ignored. Because of that the connection latency is added to the timestamps of data acquired from active connections (active agent, active proxy, sender) and subtracted from the timestamps of data acquired from passive connections (passive proxy). All other checks are done in server time and their timestamps are not adjusted.

Time synchronization

It is very important to have precise system time on server with Zabbix running. ntpd is the most popular daemon that synchronizes the host's time with the time of other machines. It's strongly recommended to maintain synchronized system time on all systems Zabbix components are running on.