GlassFish 3.1.2+ does not allow remote administration out-of-the-box. To activate remote administration you will have to set an admin password before performing the actual enabling:
asadmin change-admin-password --domain_name [DOMAIN_NAME] asadmin enable-secure-admin --port [PORT_NAME]
NEW workshop: Building HTML 5 Applications With Angular 2
Full week in December 2016: from Java EE 7 Bootstrap, Effective, Architectures over Testing to Microservices
On demand workshops: Java EE 7: Bootstrap, Effective, Testing and Microservices available for streaming.