There are commercial products that you can leave running all the time to generate data from your packets on the fly, such as ExtraHop (http://extrahop.com http:

There are commercial products that you can leave running all the time to generate data from your packets on the fly, such as ExtraHop (http://extrahop.com http://extrahop.com). There are also continuous PCAP tools, but they need massive amounts of storage and in larger environments the lookback you get is limited.