Preparing for Install

Liferay DXP doesn’t require much to deploy. You need a Java Development Kit (JDK) and a database. Several configuration topics (e.g., search engine integration, document repository configuration, security management, clustering, and more) can be addressed after deploying Liferay DXP.

Start preparing for Liferay DXP install by installing a supported Java Development Kit.

JDK Requirements

Liferay DXP deployment requires a JDK. The Support page lists the supported JDKs from various vendors. You must use one of these JDK versions:

  • JDK 8
  • JDK 11

JDK 11 is backwards compatible with JDK 8 applications. Applications and customizations developed on JDK 8 run on JDK 8 or JDK 11 runtimes. This makes JDK 8 best for developing on Liferay DXP 7.2.

JVM Requirements

Liferay DXP requires that the application server JVM use the GMT time zone and UTF-8 file encoding. Include these JVM arguments to set the required values.

-Dfile.encoding=UTF8 -Duser.timezone=GMT

On JDK 11, it’s recommended to add this JVM argument to display four-digit years.


The recommended maximum heap size is 2GB. Setting the minimum heap size to the maximum heap size value minimizes garbage collections.

-Xms2560m -Xmx2560m

If you’re using JDK 11, you may see Illegal Access warnings like these:

WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by com.liferay.petra.reflect.ReflectionUtil (file:/Users/malei/dev/project/bundles/master-bundles/tomcat-9.0.10/lib/ext/com.liferay.petra.reflect.jar) to field java.lang.reflect.Field.modifiers
WARNING: Please consider reporting this to the maintainers of com.liferay.petra.reflect.ReflectionUtil
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release

This is a known issue: LPS-87421. As a workaround, you can eliminate these warnings by adding these properties after your application server JVM options:

 --add-opens=java.base/ \
 --add-opens=java.base/java.lang.reflect=ALL-UNNAMED \
 --add-opens=java.base/java.lang=ALL-UNNAMED \
 --add-opens=java.base/ \
 --add-opens=java.base/java.nio=ALL-UNNAMED \
 --add-opens=java.base/java.text=ALL-UNNAMED \
 --add-opens=java.base/java.util=ALL-UNNAMED \
 --add-opens=java.base/ \
 --add-opens=java.desktop/java.awt.font=ALL-UNNAMED \
 --add-opens=java.rmi/sun.rmi.transport=ALL-UNNAMED \

If you’re using JDK 11 on Linux or UNIX and are activating Liferay DXP using an LCS 5.0.0 client, you may see an error like this:

ERROR [LCS Worker 2][BaseScheduledTask:92] java.lang.reflect.InaccessibleObjectException: Unable to make public long accessible: module does not
 "opens" to unnamed module @1a3325e5
java.lang.reflect.InaccessibleObjectException: Unable to make public long accessible: module does not "opens" to unnamed module @1a3325e5
at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(
at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(
at java.base/java.lang.reflect.Method.checkCanSetAccessible(
at java.base/java.lang.reflect.Method.setAccessible(

To workaround this issue, add this property after your application server JVM options:

It’s time to prepare your database.

Preparing a Database

The recommended way to set up your Liferay DXP database is also the simplest. Liferay DXP takes care of just about everything. Here are the steps:

  1. Create a blank database encoded with the character set UTF-8. Liferay DXP is a multilingual application and needs UTF-8 encoding to display all of its supported character sets.

  2. Create a database user for accessing this database. Grant this database user all rights, including the rights to create and drop tables, to the blank Liferay DXP database.

Liferay DXP uses this database user’s credentials to connect to the database either directly or through its application server. After you’ve configured the database connection, Liferay DXP creates its tables in the database automatically, complete with indexes.

This is the recommended way to set up Liferay DXP. It enables Liferay DXP to maintain its database automatically during upgrades or when various Liferay DXP plugins that create database tables of their own are installed. This method is by far the best way to set up your database.

You can connect Liferay DXP with your database using Liferay DXP’s built-in data source (recommended) or using a data source you create on your app server.

Using the Built-in Data Source

You can configure the built-in data source from the Basic Configuration page (available when Liferay DXP starts up the first time) or by specifying it using portal properties.

Here’s how set it using portal properties:

  1. Create a file if you haven’t created one already.

  2. Copy a set of jdbc.* properties from one of the JDBC templates into your file.

  3. Modify the jdbc.* property values to specify your database and database user credentials.

  4. Put the file into your LIFERAY_HOME once you’ve established it based on your installation.

Liferay DXP connects to the data source on startup.

As an alternative to the built-in data source, you can use your application server’s data source.

Using a Data Source on Your Application Server

Here’s how to use your application server’s data source:

  1. Create your data source based on the instructions in the Installing Liferay DXP on [Application Server] article (for your application server) and your application server’s documentation.

  2. Create a file, if you haven’t created one already.

  3. Add the property set to the data source’s JNDI name. Here’s an example:
  4. Put the file into your LIFERAY_HOME, once you’ve established your LIFERAY_HOME based on your installation.

Liferay DXP connects to your data source on startup.

Allowing the database user you’re using to initialize the Liferay DXP database to continue with all database rights is recommended. If you’re fine with that user having the recommended permissions, skip the next section on limiting database access.

Limiting Database Access

Even though it’s recommended for Liferay DXP to use the same database user to create and maintain its database automatically, your organizations might insist on revoking database initialization and maintenance permissions from that user once the database is initialized. If permissions for Select, Insert, Update and Delete operations are the only ones you allow for that user, you must initialize and maintain the database manually (even though it’s not recommended). Here is the manual procedure:

  1. Create a new, blank, database for Liferay DXP.

  2. Grant full rights for the Liferay DXP database user to do anything to the database.

  3. Install Liferay DXP and start it so that it automatically populates the database.

  4. Once the database has been populated with the Liferay DXP tables, remove all permissions from that user except permissions to perform Select, Insert, Update and Delete operations.

There are some caveats to running Liferay DXP like this. Many plugins create new tables when they’re deployed. Additionally, you must run the database upgrade function to upgrade Liferay DXP. If the Liferay DXP database user doesn’t have adequate rights to create/modify/drop tables in the database, you must grant those rights to that user before you deploy one of these plugins or start upgrading Liferay DXP. Once the tables are created or the upgrade completes, you can remove those rights until the next deploy or upgrade. Additionally, your own developers might create plugins that must create their own tables. These are just like Liferay DXP plugins that do the same thing, and they can only be installed if Liferay DXP can create database tables. Installing these plugins requires granting the Liferay DXP database user rights to create tables in the database before you attempt to install the plugins.

Liferay DXP has many more configurable features; but they can wait until after deployment. The Configuring Liferay DXP section explains them.

Now it’s time to install Liferay DXP.

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