Subject: Re: [PATCH net-next] ipv6: do not merge differe type and protocol routes

From: Hangbin Liu <[email-masked]>
Date: Thu, 31 Aug 2023 07:51:29 +0800

On Wed, Aug 30, 2023 at 08:49:18AM -0600, David Ahern wrote:
> On 8/30/23 12:15 AM, Hangbin Liu wrote:
> > Different with IPv4, IPv6 will auto merge the same metric routes into
> > multipath routes. But the different type and protocol routes are also
> > merged, which will lost user's configure info. e.g.
> > 
> > + ip route add local 2001:db8:103::/64 via 2001:db8:101::10 dev dummy1 table 100
> > + ip route append unicast 2001:db8:103::/64 via 2001:db8:101::10 dev dummy2 table 100
> > + ip -6 route show table 100
> > local 2001:db8:103::/64 metric 1024 pref medium
> >         nexthop via 2001:db8:101::10 dev dummy1 weight 1
> >         nexthop via 2001:db8:101::10 dev dummy2 weight 1
> > 
> > + ip route add 2001:db8:104::/64 via 2001:db8:101::10 dev dummy1 proto kernel table 200
> > + ip route append 2001:db8:104::/64 via 2001:db8:101::10 dev dummy2 proto bgp table 200
> > + ip -6 route show table 200
> > 2001:db8:104::/64 proto kernel metric 1024 pref medium
> >         nexthop via 2001:db8:101::10 dev dummy1 weight 1
> >         nexthop via 2001:db8:101::10 dev dummy2 weight 1
> > 
> > So let's skip counting the different type and protocol routes as siblings.
> > After update, the different type/protocol routes will not be merged.
> > 
> > + ip -6 route show table 100
> > local 2001:db8:103::/64 via 2001:db8:101::10 dev dummy1 metric 1024 pref medium
> > 2001:db8:103::/64 via 2001:db8:101::10 dev dummy2 metric 1024 pref medium
> > 
> > + ip -6 route show table 200
> > 2001:db8:104::/64 via 2001:db8:101::10 dev dummy1 proto kernel metric 1024 pref medium
> > 2001:db8:104::/64 via 2001:db8:101::10 dev dummy2 proto bgp metric 1024 pref medium
> > 
> > Reported-by: Thomas Haller <[email-masked]>
> > Closes: https://bugzilla.redhat.com/show_bug.cgi?id=2161994
> > Signed-off-by: Hangbin Liu <[email-masked]>
> > ---
> > All fib test passed:
> > Tests passed: 203
> > Tests failed:   0
> 
> Please add the above tests for this case to the fib tests script.

OK, I will add them and re-post after net-next open.

Thanks
Hangbin