Best software for collecting logs and NetFlow in an ISP network?

Hi everyone,

I’m looking for recommendations on software solutions for collecting and analyzing logs and NetFlow data in an ISP network. What are you using in your setups?

My main goals are:
• Efficient log collection and storage
• Real-time and historical traffic analysis
• Scalability for an ISP environment
• Preferably open-source, but commercial solutions are also of interest

Splunk
See: http://forum.mikrotik.com/t/tool-using-splunk-to-analyse-mikrotik-logs-4-0-graphing-everything/153043/1

ELK, https://www.elastic.co/guide/en/integrations/current/netflow.html