Liferay Portal allows you to run more than one portal instance on a single server. The Portal Instances page of the control panel lets you manage these instances. Data for each portal instance are kept separate from every other portal instance. All portal data, however, is kept in the same database.
Each portal instance requires its own domain name. Liferay will direct users to the proper portal instance based on this domain name. So before you configure an instance, configure its domain name in your network first. When you’re ready to add an instance, click the Add button here.
You’ll be prompted for four fields and a check box:
Web ID: A general convention is to use the domain name for this. It’s a user-generated ID for the instance.
Virtual Host: Put the domain name you configured in your network here. When users are directed to your Liferay server via this domain name, Liferay will then be able to send them to the proper portal instance.
Mail Domain: Enter the domain name for the mail host for this instance. Liferay will use this to send email notifications from the portal.
Max Users: Enter the maximum numbers of user accounts you would like your portal instance to support.
Active: Use this check box to choose whether to create an active or an inactive portal instance.
When you are finished filling out the form, click Save. Now navigate to the portal using your new domain name. You will see you are brought to what looks like a clean install of Liferay. This is your new portal instance which can now be configured any way you like.