Starting Looker Web Application looker ERROR! You are running Java Version (OpenJDK 64-Bit Server VM) which is unsupported. Please ensure that you are running Oracle Java 8 update 161+ or higher.

Last tested: Apr 26, 2019
 

As the install docs say, you needed to use Oracle Java. This stackoverflow article might help you move over.

UPDATE: We support OpenJDK 8 181+, however our Startup Scripts have a check that looks for 'java version' as opposed to 'openjdk version', so if you switch to Open JDK,  update the line in your startup script from this:

JAVA_VER=$(java -version 2>&1 | sed 's/java version "\(.*\)\.\(.*\)\..*"/\1\2/; 1q')

to this:

JAVA_VER=$(java -version 2>&1 | sed 's/openjdk version "\(.*\)\.\(.*\)\..*"/\1\2/; 1q')