From: Dufour, Andre (Andre.Dufour@PAETEC.com)
Date: Fri Mar 13 2009 - 23:05:49 ARST
Hello Johan,
HSRP cannot determine outbound traffic. It is meant to provide 1st hop-redundancy for end-users. Both routers, via their routing tables, iBGP in this case, will determine what router the traffic leaves on, regardless of which router is the HSRP active one. You should be using Local Preference within your AS to determine outbound. It would be optimal to tweak HSRP to match as best as you can, the a primary iBGP router but it is not necessary in most cases.
The path that outbound traffic leaves does not determine what path the data will take inbound; you should use as-path to help influence that. Routing must be ensures, on a per-hop-basis, in both directions. Local AS for outbound and AS-Path for inbound generally works.
Let us know if that helps.
Feel free to add more details regarding the traffic that you see.
Regards,
Andre
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of Victor
Sent: Friday, March 13, 2009 6:19 PM
To: Cisco certification; Cisco certification
Subject: Netflow V5 issue
Hi Guys,
I've some mission cirtical sites that have the following config: 2 routers with iBGP between them and also HSRP, eBGP with provider, they work one active and the other one standby. All those routers have Netflow V5 configured and I can observe that the secondary ones have traffic INBOUND but not OUTBOUND, nevertheless I can see flows on both (primary and secondary), at least BGP and a little amount of admin traffic with <sh ip cache flow> command. My question is: is that a normal behaviour?? Should I observe traffic inbound and outbound even if this router is in standby mode?
Thanks and Regards.... Johan Victor.
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