Fwd: ECMP BGP issue of more than 16 paths

4 Oct 2016

      Hi,

   I have an issue with bird routing daemon where I have EBGP between S1
and S2 with 62 paths. I am able to learn all the BGP routes with 62 paths
in bird. But the kernel only showing 16 paths.

I configured “merge paths 255” under protocol kernel, but still it shows
only 16 paths. Can somebody help me with this?

120.100.104.96/28  via 100.1.2.0 on br1003 [AG1-CR1-link0 17:06:48] * (100)
[i]

                   via 100.1.62.0 on br1063 [AG1-CR1-link61 17:07:14] (100)
[i]

                   via 100.1.59.0 on br1060 [AG1-CR1-link58 17:07:14] (100)
[i]

                   via 100.1.57.0 on br1058 [AG1-CR1-link56 17:07:14] (100)
[i]

                   via 100.1.56.0 on br1057 [AG1-CR1-link55 17:07:12] (100)
[i]

                   via 100.1.55.0 on br1056 [AG1-CR1-link54 17:07:12] (100)
[i]

                   via 100.1.54.0 on br1055 [AG1-CR1-link53 17:07:12] (100)
[i]

                   via 100.1.53.0 on br1054 [AG1-CR1-link52 17:07:12] (100)
[i]

                   via 100.1.52.0 on br1053 [AG1-CR1-link51 17:07:10] (100)
[i]

                   via 100.1.50.0 on br1051 [AG1-CR1-link49 17:07:10] (100)
[i]

                   via 100.1.47.0 on br1048 [AG1-CR1-link46 17:07:10] (100)
[i]

                   via 100.1.46.0 on br1047 [AG1-CR1-link45 17:07:10] (100)
[i]

                   via 100.1.45.0 on br1046 [AG1-CR1-link44 17:07:08] (100)
[i]

                   via 100.1.44.0 on br1045 [AG1-CR1-link43 17:07:08] (100)
[i]

                   via 100.1.42.0 on br1043 [AG1-CR1-link41 17:07:08] (100)
[i]

                   via 100.1.41.0 on br1042 [AG1-CR1-link40 17:07:08] (100)
[i]

                   via 100.1.37.0 on br1038 [AG1-CR1-link36 17:07:04] (100)
[i]

                   via 100.1.35.0 on br1036 [AG1-CR1-link34 17:07:04] (100)
[i]

                   via 100.1.34.0 on br1035 [AG1-CR1-link33 17:07:04] (100)
[i]

                   via 100.1.32.0 on br1033 [AG1-CR1-link31 17:07:04] (100)
[i]

                   via 100.1.31.0 on br1032 [AG1-CR1-link30 17:07:01] (100)
[i]

                   via 100.1.30.0 on br1031 [AG1-CR1-link29 17:07:01] (100)
[i]

                   via 100.1.29.0 on br1030 [AG1-CR1-link28 17:07:01] (100)
[i]

                   via 100.1.27.0 on br1028 [AG1-CR1-link25 17:07:01] (100)
[i]

                   via 100.1.26.0 on br1027 [AG1-CR1-link24 17:06:57] (100)
[i]

                   via 100.1.25.0 on br1026 [AG1-CR1-link23 17:06:57] (100)
[i]

                   via 100.1.21.0 on br1022 [AG1-CR1-link19 17:06:57] (100)
[i]

                   via 100.1.19.0 on br1020 [AG1-CR1-link17 17:06:57] (100)
[i]

                   via 100.1.18.0 on br1019 [AG1-CR1-link16 17:06:54] (100)
[i]

                   via 100.1.17.0 on br1018 [AG1-CR1-link15 17:06:54] (100)
[i]

                   via 100.1.15.0 on br1016 [AG1-CR1-link13 17:06:54] (100)
[i]

                   via 100.1.13.0 on br1014 [AG1-CR1-link11 17:06:54] (100)
[i]

                   via 100.1.12.0 on br1013 [AG1-CR1-link10 17:06:51] (100)
[i]

                   via 100.1.9.0 on br1010 [AG1-CR1-link7 17:06:51] (100)
[i]

                   via 100.1.7.0 on br1008 [AG1-CR1-link5 17:06:51] (100)
[i]

                   via 100.1.5.0 on br1006 [AG1-CR1-link3 17:06:51] (100)
[i]

                   via 100.1.3.0 on br1004 [AG1-CR1-link1 17:04:43] (100)
[i]

                   via 100.1.63.0 on br1064 [AG1-CR1-link62 17:05:54] (100)
[i]

                   via 100.1.61.0 on br1062 [AG1-CR1-link60 17:05:54] (100)
[i]

                   via 100.1.60.0 on br1061 [AG1-CR1-link59 17:05:54] (100)
[i]

                   via 100.1.58.0 on br1059 [AG1-CR1-link57 17:05:49] (100)
[i]

                   via 100.1.51.0 on br1052 [AG1-CR1-link50 17:05:49] (100)
[i]

                   via 100.1.49.0 on br1050 [AG1-CR1-link48 17:05:49] (100)
[i]

                   via 100.1.48.0 on br1049 [AG1-CR1-link47 17:05:49] (100)
[i]

                   via 100.1.43.0 on br1044 [AG1-CR1-link42 17:05:43] (100)
[i]

                   via 100.1.40.0 on br1041 [AG1-CR1-link39 17:05:43] (100)
[i]

                   via 100.1.39.0 on br1040 [AG1-CR1-link38 17:05:43] (100)
[i]

                   via 100.1.38.0 on br1039 [AG1-CR1-link37 17:05:43] (100)
[i]

                   via 100.1.36.0 on br1037 [AG1-CR1-link35 17:05:39] (100)
[i]

                   via 100.1.33.0 on br1034 [AG1-CR1-link32 17:05:39] (100)
[i]

                   via 100.1.28.0 on br1029 [AG1-CR1-link27 17:05:39] (100)
[i]

                   via 100.1.24.0 on br1025 [AG1-CR1-link22 17:05:39] (100)
[i]

                   via 100.1.23.0 on br1024 [AG1-CR1-link21 17:05:36] (100)
[i]

                   via 100.1.22.0 on br1023 [AG1-CR1-link20 17:05:36] (100)
[i]

                   via 100.1.20.0 on br1021 [AG1-CR1-link18 17:05:36] (100)
[i]

                   via 100.1.16.0 on br1017 [AG1-CR1-link14 17:05:36] (100)
[i]

                   via 100.1.14.0 on br1015 [AG1-CR1-link12 17:05:35] (100)
[i]

                   via 100.1.11.0 on br1012 [AG1-CR1-link9 17:05:35] (100)
[i]

                   via 100.1.10.0 on br1011 [AG1-CR1-link8 17:05:35] (100)
[i]

                   via 100.1.8.0 on br1009 [AG1-CR1-link6 17:05:35] (100)
[i]

                   via 100.1.6.0 on br1007 [AG1-CR1-link4 17:05:35] (100)
[i]

                   via 100.1.4.0 on br1005 [AG1-CR1-link2 17:05:35] (100)
[i]

# ip route list 120.100.104.96/28

120.100.104.96/28  proto bird

        nexthop via 100.1.2.0  dev br1003 weight 1

        nexthop via 100.1.3.0  dev br1004 weight 1

        nexthop via 100.1.4.0  dev br1005 weight 1

        nexthop via 100.1.5.0  dev br1006 weight 1

        nexthop via 100.1.6.0  dev br1007 weight 1

        nexthop via 100.1.7.0  dev br1008 weight 1

       nexthop via 100.1.8.0  dev br1009 weight 1

        nexthop via 100.1.9.0  dev br1010 weight 1

        nexthop via 100.1.10.0  dev br1011 weight 1

        nexthop via 100.1.11.0  dev br1012 weight 1

        nexthop via 100.1.12.0  dev br1013 weight 1

        nexthop via 100.1.13.0  dev br1014 weight 1

        nexthop via 100.1.14.0  dev br1015 weight 1

        nexthop via 100.1.15.0  dev br1016 weight 1

        nexthop via 100.1.16.0  dev br1017 weight 1

        nexthop via 100.1.17.0  dev br1018 weight 1

router id 100.0.2.1;

log syslog all;

protocol kernel {

        scan time 60;

        import all;

        merge paths 255;

        export all;   # Actually insert routes into the kernel routing table

}

Thanks,

Madhu