When zone and cluster aggregation is selected when prom. as datasource is used topology and overview pages doesn't show data as those metrics are not available 

1. Enable multiClusterDeployment and addZone in processor config of flowcollector
2. In Netflow Traffic page, Select DataSource as Prometheus
3.

overview and topology panels are not available with info:

Can't build query: this request could not be performed with Prometheus metrics, as they are missing some of the required labels. Try using different filters and/or aggregations. For example, try removing these dependencies from your query: SrcK8S_Zone, DstK8S_Zone. Alternatively, you may also install and enable Loki

Can't build query: this request could not be performed with Prometheus metrics, as they are missing some of the required labels. Try using different filters and/or aggregations. For example, try removing these dependencies from your query: K8S_Clustername. Alternatively, you may also install and enable Loki

metrics should be available for zone and cluster as these are not of high cardinality