[Routing Issue] There are two same net range routing on routing table.

[이재용]

Thank you for your reply.
Unfortunately, There is no krt_metric in my configure.

protocol kernel 
{
persist; scan time 20; merge paths on; ipv4 {import none; export all;
};
}

i'm using "merge paths on" option for ecmp. 
is this option can be problem?

-----Original Message-----From:  "Alexander Zubkov" <green at qrator.net>To:     "이재용" <jaeyong.lee at nhn.com>; Cc:     "BIRD Users" <bird-users at network.cz>; Sent:  2024-06-03 (월) 14:17:50 (UTC+09:00)Subject: Re: [Routing Issue] There are two same net range routing on routing table.Hi,
Do you alter krt_metric in you kernel protocol export filter? That could cause such problem. There was recently a question about it in this mailing list.

Regards, 
Alexander

On Mon, Jun 3, 2024, 03:40 이재용 <jaeyong.lee at nhn.com mailto:jaeyong.lee at nhn.com> wrote:
Hello,

We use BIRD for communication with servers with higher-level switches.

But recently we came across the following case:
server run as a ecmp routing.
10.171.0.0/24 http://10.171.0.0/24 proto bird
    nexthop via 10.171.0.25 dev p0 weight 1
    nexthop via 10.171.1.25 dev p1 weight 1
For a change higher-level switches, we adjusted our ibgp LP value to flow traffic as a one path.  As we expected, servers routing are changed as one path routing 
10.171.0.0/24 http://10.171.0.0/24 proto bird
but, one server has a two same net range routing. like this sample
case1) 
10.171.0.0/24 http://10.171.0.0/24 proto bird10.171.0.0/24 http://10.171.0.0/24 proto bird metric 32
    nexthop via 10.171.0.25 dev ${interface1} 
    nexthop via 10.171.1.25 dev ${interface2} 
case2 )
10.171.0.0/24 http://10.171.0.0/24 proto bird metric 3210.171.0.0/24 http://10.171.0.0/24 proto bird
    nexthop via 10.171.0.25 dev ${interface1} 
    nexthop via 10.171.1.25 dev ${interface2} 
in case1, there was any problem , but in case 2 it had. (flow packet as two paths)in my thought, pervious routing not deleted. So, two same range is now avaliable.if there are someone who have same problem, would you advise for this problem? 






-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://trubka.network.cz/pipermail/bird-users/attachments/20240609/14b1af76/attachment.htm>