Description of problem:

'Adding a New Cluster' section in the operations guide for 3.10, 3.11 and in 3.9 doc, needs to be updated to have gluster related firewall ports to be opened up in order to create the additional cluster.

https://access.redhat.com/documentation/en-us/red_hat_openshift_container_storage/3.11/html-single/operations_guide/index#idm140486997277856

doc links: 

OCS 3.11 - https://access.redhat.com/documentation/en-us/red_hat_openshift_container_storage/3.11/html-single/operations_guide/index#idm140486997277856

OCS 3.10 - https://access.redhat.com/documentation/en-us/red_hat_openshift_container_storage/3.10/html/operations_guide/chap-documentation-red_hat_gluster_storage_container_native_with_openshift_platform-managing_clusters#idm140027224798800

CNS 3.9 - https://access.redhat.com/documentation/en-us/container-native_storage-deprecated/3.9/html-single/container-native_storage_for_openshift_container_platform/#idm140266793713808 

p.s., I'm raising a single doc bug for the same, let me know if this has to be cloned for each of the releases separately.

Version-Release number of selected component (if applicable):
3.9, 3.10 & 3.11