The information for configuration of DNS_Ping should be at this location.

https://docs.redhat.com/en/documentation/red_hat_data_grid/8.5/html/embedding_data_grid_in_java_applications/cluster-transport#discovery-dns-ping_cluster-transport

specifically the information about how you should create your headless service.  

This whole section in https://docs.redhat.com/en/documentation/red_hat_data_grid/7.3/html-single/red_hat_data_grid_for_openshift/index#os_cluster_discovery_dns

Should be ported Over.  

Everything in the 7.3 section seems right, except we no longer use the toleration, "
service.alpha.kubernetes.io/tolerate-unready-endpoints: 'true'
 
We now use spec.publishNotReadyAddresses: true.  Here's an example of how to set up the spec for your headless service needed for dg to join the pods
 
 

spec: 
  type: ClusterIP 
  clusterIP: None 
  publishNotReadyAddresses: true