The RabbitMQ environment variables

RabbitMQ environment variables is one of the configuration ways of RabbitMQ. Every operating system has its own set of environment variables for each user. Although operating systems has the ability to have environment variables, the way in which environment variables are changed is slightly different across operating systems.

In Unix-based operating systems, we can change the environment variables rather easily using the rabbitmq-env.conf file. In the environment configuration file, we can add the environment parameters as follows:

CONFIG_FILE=/etc/rabbitmq/testfile

After changing the rabbitmq-env.conf file, we have to restart the RabbitMQ server to reload the environment variables.

In Windows, we should use the environment variables of the System Properties for modifying the environment variables of RabbitMQ. We can access to the Environment Variables by navigating to Settings | Control Panel | System Properties | Advanced | Environment Variables, where we use pipes to show transitions. You can see this in the following screenshot:

Windows Environment Parameters

We are now accessing the environment variables of different operating systems. Although, RabbitMQ gives us lots of different environment variables, we will cover the most important ones.

Common environment variables

RabbitMQ gives us lots of great environment variables to control all of the parts of its engine. We don't have enough time to discuss all of the environment variables; however, we will talk about the most important ones. Furthermore, some variables have different default values for Unix and Windows operating systems; we'll consider these variables in the following parts of the topic. Anyway, let's dive into the important variables:

• RABBITMQ_BASE: This variable basically locates the directory of RabbitMQ. This directory has the database and log files.
• RABBITMQ_CONFIG_FILE: Although the configuration file of RabbitMQ has a default location, you can change its location using this environment variable.
• RABBITMQ_LOGS: RabbitMQ supports different levels of logs. Whenever RabbitMQ is creating a log file, it has a default location; however, you can change its location using this environment variable.
• RABBITMQ_NODE_IP_ADDRESS: RabbitMQ binds to all network interfaces as a default property. As RabbitMQ gives us a full control over network interfaces, we can easily change its binding network using this variable, such as 127.0.0.1.
• RABBITMQ_NODE_PORT: RabbitMQ has a default port, 5672; however, we have sometimes collision on ports, so we should change the ports that RabbitMQ binds. We can change RabbitMQ's binding port using this variable.
• RABBITMQ_PLUGINS_DIR: RabbitMQ has many very useful plugins that will be enabled through RabbitMQ. RabbitMQ has a default location for these Erlang coded plugins; however, you can change its location.

The RabbitMQ Environment Variables:

Cells marked with* will be explained in the Unix and Windows section

Unix-specific default location

The following table describes the Unix-specific default locations of the given environment variables. Most of the locations are related to the installed location.

Default locations of environment variables for Unix:

Windows-specific default location

In contrast to Unix, Windows default values of the RabbitMQ environment variables are related to the other environment variables of RabbitMQ. The following table shows the Windows default locations.

Default locations of environment variables for Windows:

RabbitMQ environment variables are highly dependent on operating system environment variables. As an example, Computer Name in Unix and Hostname in Windows set the environment variable RABBITMQ_SERVICENAME and RABBITMQ_NODENAME. Anyway, the following table describes the dependent environment variables: