[j-nsp] Using the FXP for flow sources

[Tyler Christiansen]

This is platform-dependent.  Some platforms (definitely EX, probably SRX)
use the RE for processing flow data--so you can use fxp0.  Other platforms
(MX) use the PFE, which is why fxp0 is not a valid interface.

I did some testing on this a few months ago to confirm that EX switches (at
least 3200, 3300, 4200, 4500, and 4550) use RE and MX uses PFE.  I think I
tested our SRX550, too, and saw that it used RE.  I honestly don't recall
the results of the SRX test, though.

You can find out pretty easily--if you enable it and you can see flow
traffic using tcpdump on the SRX (or monitor traffic), it's handled by the
RE.  If you _don't_ see flow data (but you know it's actually being sent),
it's handled by the PFE.

--tc


On Thu, Aug 21, 2014 at 10:09 AM, Scott Granados <scott at granados-llc.net>
wrote:

> Hi,
>         So I’m still a bit confused on what can or can’t be used in the
> flow monitoring processes.  In this case I have an SRX 3600 with a routing
> instance.  I found a config example that illustrates how to enable flow
> sampling in this type of environment.  It specifically mentions that you
> use a source IP with in the global routing table and not the instance.  In
> my case the only interface I have in the global instance is fxp0.0
> (management).  I have read in the case of the MX you can’t use the
> management interface asa flow source.  I haven’t been able to find anything
> regarding the SRX.  Is FXP0 a valid source for flow monitoring or do I need
> to create another interface, maybe a loopback, with in the global
> instance?  Also, is there a good document that details better the
> limitations of flow monitoring on the SRX.  I’ve found some bits and pieces
> but nothing centralized.  Any pointers would be most appreciated.
>
> Thanks
> Scott
>
>
> _______________________________________________
> juniper-nsp mailing list juniper-nsp at puck.nether.net
> https://puck.nether.net/mailman/listinfo/juniper-nsp
>



-- 

*Tyler Christiansen | Technical Operations*
tyler <http://adap.tv/>@adap.tv <http://adap.tv/> | www.adap.tv
*m :* 864.346.4095