Bug 2104153

Summary: [ODF] What should be the minimum size of the subnet in a multus deployment for all storage traffic, public and cluster
Product: [Red Hat Storage] Red Hat OpenShift Data Foundation Reporter: Direct Docs Feedback <ddf-bot>
Component: documentationAssignee: Anjana Suparna Sriram <asriram>
Status: NEW --- QA Contact: Neha Berry <nberry>
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Priority: medium    
Version: 4.10CC: arolivei, muagarwa, odf-bz-bot, shan
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Description Direct Docs Feedback 2022-07-05 16:36:12 UTC 
What should be the minimum size of the subnet in a multus deployment for all storage traffic, public and cluster on the same interface?  While working with an edge use case in a 3-node compact cluster setup, we may keep in mind that some customers/partners, may not be able to provide a full /24 range in remote edge locations. 

Reported by: rhn-support-arolivei

https://access.redhat.com/documentation/en-us/red_hat_openshift_data_foundation/4.10/html/planning_your_deployment/infrastructure-requirements_rhodf#annotations:1c03870c-f6c6-4915-9d67-7dba2beef8b3
Comment 5 Sébastien Han 2022-07-21 12:53:19 UTC 
If public and cluster network are separated, we need two different subnets.
Each storage node needs two IPs one in each subnet.
Also, we need to include the holder/node components from csi, so 2 IPs per node (they don't need access to the cluster network).

From that, even allocating /24 which gives us around 252 IPs should be sufficient for most of the clusters.
Hope this helps.