5 Replies Latest reply on Apr 14, 2013 9:08 PM by superfly99

    To loopback or not to loopback (with NTA)

    donc1972

      Hello all!  Quick question, and to be honest, I should just try it in the lab, but I'm feeling extra lazy today.  I have NTA deployed on my 100 of 200 plus MPLS routers which is working like a champ, I'm getting flow details and it is helping us out.   But as I develop a "config standard" to get this rolled out to the rest of the enterprise, I am considering changing the source to the loopback and not the Mu1 or xyz egress/ingress point for the sites.  Is there a best practice?  I am guessing if I go with Lo0 (or whatever loop we have set..) it will pick up on all of the interfaces.  How do you do it in your environment?  Am I missing a step?  I am getting the flows, and I do get the "unknown" interfaces found, which I promptly add, but is there a more efficient way to roll it out? 

       

      Cisco Example:

       

      ip flow-export source interface Mulilink1

      ip flow-export version 5

      ip flow-export destination X.X.X.X 2055

       

      Juniper Example:

       

      [edit interfaces ge-0/2/0 unit 402 family inet]

      +       /* Configure sampling to collect packets for J-Flow */

      +       sampling {

      + input;

      + output;

      +       }

      [edit interfaces ge-0/2/0 unit 407 family inet]

      +       /* Configure sampling to collect packets for J-Flow */

      +       sampling {

      + input;

      + output;

      +       }

      [edit interfaces ge-0/2/0 unit 416 family inet]

      +       /* Configure sampling to collect packets for J-Flow */

      +       sampling {

      + input;

      + output;

      +       }

      [edit interfaces ge-0/2/0 unit 426 family inet]

      +       /* Configure sampling to collect packets for J-Flow */

      +       sampling {

      + input;

      + output;

      +       }

      [edit interfaces ge-0/2/0 unit 430 family inet]

      +       /* Configure sampling to collect packets for J-Flow */

      +       sampling {

      + input;

      + output;

      +       }

      [edit interfaces ge-0/2/0 unit 432 family inet]

      +       /* Configure sampling to collect packets for J-Flow */

      +       sampling {

      + input;

      + output;

      +       }

      [edit interfaces ge-0/2/0 unit 624 family inet]

      +       /* Configure sampling to collect packets for J-Flow */

      +       sampling {

      + input;

      + output;

      +       }

      [edit]

      +  forwarding-options {

      +      sampling {  

      +          input {

      + /* Collect 1 packet out of every 100 sent */

      + rate 100;

      +          }

      +          family inet {

      + output {

      + flow-server x.x.x.x. {

      + port 9995;

      + autonomous-system-type origin;

      + version 5;

      + }

      + }

      +          }

      +      }

      +  }