Bug 2088565

Describe the issue
==================

In chapter dealing with installation of ODF storage system in external mode, we
are just referencing to "Deploying OpenShift Data foundation in external
mode" guide without highlighting peculiarities of MetroDR environment.

Describe the task you were trying to accomplish
===============================================

Install storage system for MetroDR with ACM environment.

Suggestions for improvement
===========================

In chapter dealing with installation of ODF storage system in external mode,
we need to explain/highlight at least the following peculiarities of MetroDR
with ACM which could be missed:

- list of options (or group of options) of
  ceph-external-cluster-details-exporter.py script which should be specified in
  MetroDR environment (I assume that one needs to specify at least
  --rbd-data-pool-name option, --cephfs-* options and --rgw-endpoint)

- if some option won't work with metro dr, we should highlight it as not
  supported (I'm not aware of such option, but let's recheck that when fixing
  this)

- note whether I need monitoring-endpoint for proper function of MetroDR setup

- note that one needs to run the exporter script twice, since each ODF storage
  system needs to get reference to rgw endopoint in the same zone

Listing this would stress what is expected and supported configuration,
prevent misconfiguration and make deployment of MetroDR systems easier.

We don't need to go into details, but we need to address assumptions which
stems from the MetroDR use case.

Document URL
============

https://access.redhat.com/documentation/en-us/red_hat_openshift_data_foundation/4.10/html/configuring_openshift_data_foundation_for_metro-dr_with_advanced_cluster_management/installing-odf-operator-on-managed-clusters_rhodf

Chapter/Section Number and Title
================================

Chapter 5. Installing OpenShift Data Foundation on managed clusters

Product Version
===============

ODF 4.10

Environment Details
===================

MetroDR with ACM: connecting ODF storage system on 2 OCP cluster with one
external ceph stretched in zones of these 2 OCP clusters.

Any other versions of this document that also needs this update
===============================================================

This text was introduced in 4.10, and should be fixed at least in 4.11.

Additional information
======================

The assumptions should be acknowledged by ODF developers. I could be wrong
(which is another reason to state these details directly in the docs).

Additional information about RGW and zones in MetroDR environment
=================================================================

Assuming I have:

- 2 RGW endpoints, one in each zone of a stretched cluster
- OCP1 is in the zone where 1st half of stretched ceph, RGW is running there in
  ceph-2 machine
- OCP2 is in the zone where 2nd half of stretched ceph, RGW is running there
  ceph-5 machine

Which would look like this from ceph point of view:

```
[root@ceph-0 ~]# ceph -s | grep rgw                                              
    rgw: 2 daemons active (2 hosts, 1 zones)                                    
[ceph: root@ceph-0 /]# ceph orch ps --daemon_type=rgw                            
NAME                        HOST                                   PORTS   STATUS        REFRESHED  AGE  MEM USE  MEM LIM  VERSION           IMAGE ID      CONTAINER ID
rgw.objectgw.ceph-2.upbjyy  ceph-2.mbukatov-ceph01.qe.example.com  *:8080  running (2d)     9m ago   2d    68.7M        -  16.2.7-112.el8cp  cf1c8f1da91f  18d05e3f4d1d
rgw.objectgw.ceph-5.qswtya  ceph-5.mbukatov-ceph01.qe.example.com  *:8080  running (2d)     9m ago   2d    68.4M        -  16.2.7-112.el8cp  cf1c8f1da91f  9645cba03f00
```

I need to export the json 2 times, for each OCP/ODF/zone, for example:

```
# python3 ceph-external-cluster-details-exporter.py --rbd-data-pool-name rbdpool --cephfs-filesystem-name fs_foo --cephfs-metadata-pool-name cephfs.fs_foo.meta --cephfs-data-pool-name cephfs.fs_foo.data --rgw-endpoint ceph-2.mbukatov-ceph01.qe.example.com:8080 > ocp1.json
# python3 ceph-external-cluster-details-exporter.py --rbd-data-pool-name rbdpool --cephfs-filesystem-name fs_foo --cephfs-metadata-pool-name cephfs.fs_foo.meta --cephfs-data-pool-name cephfs.fs_foo.data --rgw-endpoint ceph-5.mbukatov-ceph01.qe.example.com:8080 > ocp2.json
```