bgpd: imported evpn rt5 routes copy igpmetric

when doing BGP over an IGP platform, the expectation is that
the path calculation for a given prefix takes into account the
igpmetric given by IGP.
This is true with prefixes obtained in a given BGP instance where
peering occurs. For instance, ipv4 unicast entries or l2vpn evpn
entries work this way. The igpmetric is obtained through nexthop
tracking, like below:

south-vm# show bgp nexthop
Current BGP nexthop cache:
 1.1.1.1 valid [IGP metric 10], #paths 1, peer 1.1.1.1
 2.2.2.2 valid [IGP metric 20], #paths 1, peer 2.2.2.2

The igp metric is taken into account when doing best path
selection, and only the entry with lowest igp wins.

[..]
*>i[5]:[0]:[32]:[5.5.5.5]
                    1.1.1.1                  0    100      0 ?
                    RT:65400:268435556 ET:8 Rmac:2e:22:6c:67:bb:73
* i                 2.2.2.2                  0    100      0 ?
                    RT:65400:268435556 ET:8 Rmac:f2:d3:68:4e:f4:ed

however, for imported EVPN RT5 entries, the igpmetric was not
copied from the parent path info. Fix it. In this way, the
imported route entries use the igpmetric of the parent pi.

Signed-off-by: Philippe Guibert <philippe.guibert@6wind.com>
(cherry picked from commit 56c70d87149ebdf9f399a882b3ecd1cec4e84b76)

diff --git a/bgpd/bgp_evpn.c b/bgpd/bgp_evpn.c
index c6a134114c7e25463c545eb5052516f9b7353408..8d8e3ffd2ee36f08ea4eaa7e8611f901305885ef 100644 (file)
--- a/bgpd/bgp_evpn.c
+++ b/bgpd/bgp_evpn.c
@@ -2340,6 +2340,7 @@ bgp_create_evpn_bgp_path_info(struct bgp_path_info *parent_pi,
                memcpy(&pi->extra->label, &parent_pi->extra->label,
                       sizeof(pi->extra->label));
                pi->extra->num_labels = parent_pi->extra->num_labels;
+               pi->extra->igpmetric = parent_pi->extra->igpmetric;
        }
        bgp_path_info_add(dest, pi);