4 Replies Latest reply on Dec 27, 2007 4:11 PM by floyd.may

    Netflow Collector Behind NAT


      We are trying to get the Netflow traffic analyzer setup.  The Netflow collector is on a NATed network.  We have several inter-office users on the same LAN as this collector.  Whenever we start the Solar Winds Netflow service, all local users are unable to accomplish any web browsing.  They are able to access cached pages, but nothing else. The moment we stop the service, things return to normal.

       Any ideas?

        • Re: Netflow Collector Behind NAT

          Can you explain your topology in more detail?  Specifically, where are the NetFlow Router(s), SQL database, DNS server(s), etc. in relation to your NAT?  A diagram would be most helpful.

           At first glance, I can't see how starting & stopping the NetFlow collector could possibly have any impact on other hosts' connectivity.  The only things that the NetFlow collector are doing on the network are:

          1. Receiving NetFlow packets.  These packets are already being sent, though, so starting the service would, in some cases, actually be lowering the total traffic across the network because there wouldn't be ICMP port unreachable messages.
          2. Doing DNS requests.
          3. Communicating with the SQL database.
          None of these should be affecting other hosts' connectivity.
          • Re: Netflow Collector Behind NAT

             What other apps or services are running on the netflow collector server?