JBCS Apache yum repository name for RHEL8 "jb-coreservices-1-for-rhel-8-x86_64-rpms" is not written in the JBCS Apache Installation Guide.

JBCS Apache modules for RHEL8 such as mod_jk and mod_cluster are distributed by "jb-coreservices-1-for-rhel-8-x86_64-rpms" channel, not RHEL's rhel-8-for-x86_64-appstream-rpms. Customers have to explicitly enable the JBCS repository to install JBCS Apache modules in addition to RHEL's repository.

I think it would be better to add like the following to 2.2.1. Using mod_jk,mod_cluster, mod_rt, and mod_bmx with RHEL 8

2.2.1. Using mod_jk,mod_cluster, mod_rt, and mod_bmx with RHEL 8

This section cover proper procedure to install and configure the JBCS modules; mod_jk, mod_cluster, mod_rt, and mod_bmx on the RHEL 8 OS.

+Subscribe to the Apache HTTP Server CDN repository for RHEL8
+# subscription-manager repos --enable="jb-coreservices-1-for-rhel-8-x86_64-rpms"

Installing httpd
To install httpd run the following command with root access:
$ yum install httpd
...