On doc page here : https://access.redhat.com/documentation/en-us/red_hat_jboss_web_server/5.3/html-single/installation_guide/index#installing_from_rpm The package names are incorrect here:

For Red Hat Enterprise Linux 8:

• jws-5-for-rhel-8-server-rpms
• jb-coreservices-1-for-rhel-8-server-rpms

Must be:

For Red Hat Enterprise Linux 8:

• jws-5-for-rhel-8-x86_64-rpms
• jb-coreservices-1-for-rhel-8-x86_64-rpms