Environment Variable

Environment Variables:

Environment variables store the values of the frequently used parameters, that are provided to a software program at runtime. Setting and using such placeholders instead of specifying the required values in the application code each time they are needed, makes your application more portable and flexible. It brings even more convenience if these values may differ from one host to another.

Each BitssCloud-managed software stack is provided with a number of default variables, which display all the significant container information to help developers with application hosting.

BitssCloud PaaS also gives you the possibility to declare your own custom environment variables (user-defined parameters) by means of adding the needed values to a special configuration file and in such a way, keeping them out of the code. Inside this file, you can set placeholders for your folder names, usernames, passwords, hosts, IP addresses, etc instead of hardcoding their values to every file they are required in.

• Default Environment Variables:

Within variables, BitssCloud provides the data on the created stack. Most of them are just informational (marked within tables below) and do not have any actual effect on the container. For example, using the TOMCAT_VERSION variable you can compare versions of the running Tomcat server and the one required by your application (to ensure compatibility), but changing its value won’t upgrade your container.

• There is a number of options available for all software stack templates:

Variable	Value Example	Description
CLONE_ON_SCALE	FALSE	Defines if new nodes upon horizontal scaling should be clones of a layering master (true) or created from scratch (false)
DOCKER_EXPOSED_PORT	7979,8009,8743,21,22,25,443,80,8080	Lists ports from the EXPOSE directive of the image’s docker file, which will be opened via container firewall during environment creation (informational)
BitssCloud_PORTS	3306/tcp, 33061/udp, 33062	Specifies custom ports, which will be opened via container firewall during environment creation
PATH	/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin	A default shell variable, with a list of paths to directories with executable programs (informational)
STACK_PATH	/opt/tomcat	Stack home directory (informational)
STACK_USER	tomcat	Name of the default user for the stack (informational)
STACK_VERSION	9.0.5	A version of the current template (informational)
MASTER_IP	192.168.4.210	The internal IP address of a master node within a layer (informational)
MASTER_ID	162713	Unique node identifier of a master node within a layer (informational)
MASTER_HOST	node162713	A short hostname for a master node within a layer (informational)