rdma.service was included in the rdma package (latest: rdma-7.3_4.7_rc2-6.el7_3.noarch.rpm) provided up to RHEL7.3, but since then the package has been replaced by rdma-core, in which does not provide rdma.service.

Therefore, it would be inappropriate to provide instructions for restarting rdma.service after modifying /etc/rdma/modules/rdma.conf in RHEL8.

In fact, if we modify /etc/rdma/modules/*.conf, we need to restart rdma-load-modules@*.service, or if the service has already been started, we need to add or remove the module individually by modprobe command, or reboot the system. 

Am I right?

Reported by: rhn-support-hkanda

https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/configuring_infiniband_and_rdma_networks/configuring-the-core-rdma-subsystem_configuring-infiniband-and-rdma-networks#annotations:cff49a33-219a-4266-9dda-b3ce3486f6bc