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Date: Mon, 26 May 2008 00:58:48 GMT
From: Barrett Lyon <blyon@blyon.com>
To: freebsd-gnats-submit@FreeBSD.org
Subject: ECMP does not remove/disable next-hop for downed GRE interface
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>Number:         123992
>Category:       kern
>Synopsis:       [ecmp] ECMP does not remove/disable next-hop for downed GRE interface
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    qingli
>State:          closed
>Quarter:        
>Keywords:       
>Date-Required:  
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon May 26 01:10:02 UTC 2008
>Closed-Date:    Fri Dec 04 18:25:57 UTC 2009
>Last-Modified:  Fri Dec 04 18:25:57 UTC 2009
>Originator:     Barrett Lyon
>Release:        8.0-CURRENT
>Organization:
>Environment:
FreeBSD home.blyon.com 8.0-CURRENT FreeBSD 8.0-CURRENT #3: Sun May 25 02:18:13 PDT 2008     blyon@home.blyon.com:/usr/obj/usr/src/sys/GENERIC  i386


>Description:
Using RADIX_MPATH support in the kernel provides the desired ECMP support.

I have two GRE tunnels setup with two routes defined for the same destination.  When using ifconfig to down one of the tunnels, the route/next-hop for the downed tunnel stays active.

I would assume that once the GRE tunnel is down, the network on that interface is no longer available, thus the next-hop on that network should also no longer be an active next-hop.

This appears to work with if_em.


>How-To-Repeat:
Create two GRE tunnels, create two routes for the same destination address which route over the two GRE interfaces.

Verify that ECMP is working over the two interfaces, then down/disable one GRE interface with ifconfig and traffic goes to a bit bucket.
>Fix:
none

>Release-Note:
>Audit-Trail:
Responsible-Changed-From-To: freebsd-bugs->qingli 
Responsible-Changed-By: linimon 
Responsible-Changed-When: Wed May 28 02:47:23 UTC 2008 
Responsible-Changed-Why:  
Over to committer. 

http://www.freebsd.org/cgi/query-pr.cgi?pr=123992 
State-Changed-From-To: open->closed 
State-Changed-By: qingli 
State-Changed-When: Fri Dec 4 18:24:30 UTC 2009 
State-Changed-Why:  
This limitation should be resolved by the flow-table implementation that is 
part of Release 8.0. 


http://www.freebsd.org/cgi/query-pr.cgi?pr=123992 
>Unformatted:
