Plixer’s Scrutinizer is the gold standard. The free version is limited to and keeps data for 5 hours of raw detail (aggregated views go back 30 days). For most SMBs and labs, 10k fps is huge.
It runs best on a dedicated VM (Windows or Linux). The interface is powerful but has a 2010-era learning curve. 2. ntopng (Community Edition) Best for: Real-time visibility and edge monitoring. free netflow monitor
The community edition caps at 1 million active flows . That’s fine for branch offices or labs, but not a core data center. 3. ELK Stack (Elasticsearch, Logstash, Kibana) + ElastiFlow Best for: DIY warriors who want unlimited scalability. Plixer’s Scrutinizer is the gold standard
ElastiFlow is an open-source template that turns Elasticsearch into a NetFlow collector. You bring the servers, it brings the network analytics. It runs best on a dedicated VM (Windows or Linux)
The security investigation tools. You can drill from “High UDP traffic” straight into a flow grid, apply a filter for “Deny” actions, and pivot to a geo-map. No other free tool matches its threat-hunting workflow.