TOR-BMS: Broadcast traffic is getting replicated for Invalid EVPN next hop and discarded

[chhandak]

Broadcast route is always getting programmed with EVPN next hop. So even if there is no MX to flood traffic still it is programmed in composite next hop.

In turn vrouter is replicating the traffic for EVPN next hop and eventually getting discarded. So drop stats count is increasing.

root@nodei9:~# dropstats | grep Disca
IF TX Discard 0
IF RX Discard 0
Discards 327343108
root@nodei9:~# dropstats | grep Disca
IF TX Discard 0
IF RX Discard 0
Discards 327523369 >>>>>>>>>>>Count increasing

root@nodei9:~# tcpdump -ni bond0 udp port 4789 -c 3
tcpdump: WARNING: bond0: no IPv4 address assigned
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on bond0, link-type EN10MB (Ethernet), capture size 65535 bytes
02:30:16.744468 IP 34.34.34.34.23898 > 192.168.22.4.4789: VXLAN, flags [I] (0x08), vni 4760
IP 130.1.1.5 > 130.1.1.6: ip-proto-255 22
02:30:16.744470 IP 34.34.34.34.23898 > 192.168.22.4.4789: VXLAN, flags [I] (0x08), vni 4760
IP 130.1.1.5 > 130.1.1.6: ip-proto-255 22
02:30:16.744471 IP 34.34.34.34.23898 > 192.168.22.4.4789: VXLAN, flags [I] (0x08), vni 4760
IP 130.1.1.5 > 130.1.1.6: ip-proto-255 22

root@nodei9:~# vxlan --get 4760
VXLAN Table

 VNID NextHop
----------------
   4760 18293
root@nodei9:~#
root@nodei9:~#
root@nodei9:~# nh --get 18293
Id:18293 Type:Vrf_Translate Fmly: AF_INET Flags:Valid, Vxlan, Unicast Flood, Rid:0 Ref_cnt:2 Vrf:52
              Vrf:52

root@nodei9:~# rt --dump 52 --family bridge
Kernel L2 Bridge table 0/52

Flags: L=Label Valid, Df=DHCP flood

Index DestMac Flags Label/VNID Nexthop
301580 0:0:5e:0:1:0 Df - 3
526228 0:17:1:1:1:2 - 1
533228 0:37:1:1:1:2 - 1
629352 0:37:1:1:1:1 L 4760 16
635120 0:25:90:e4:8:e4 Df - 3
837980 0:17:1:1:1:1 - 1
965652 2:c5:db:98:f0:8a LDf 17 14
983128 ff:ff:ff:ff:ff:ff LDf 4760 18300

root@nodei9:~# nh --get 18300
Id:18300 Type:Composite Fmly:AF_BRIDGE Flags:Valid, Multicast, L2, Rid:0 Ref_cnt:4 Vrf:52
              Sub NH(label): 18297(0) 18299(0) 18295(0)

root@nodei9:~# nh --get 18297
Id:18297 Type:Composite Fmly: AF_INET Flags:Valid, Tor, Rid:0 Ref_cnt:2 Vrf:52
              Sub NH(label): 16(4760)

root@nodei9:~# nh --get 16
Id:16 Type:Tunnel Fmly: AF_INET Flags:Valid, Vxlan, Rid:0 Ref_cnt:1728 Vrf:0
              Oif:0 Len:14 Flags Valid, Vxlan, Data:50 c5 8d a0 f1 40 00 25 90 e4 08 e4 08 00
              Vrf:0 Sip:192.168.22.4 Dip:34.34.34.34

root@nodei9:~# nh --get 18299 >>>>>>>>>>>>>>>>EVPN is present as next hop
Id:18299 Type:Composite Fmly: AF_INET Flags:Valid, Evpn, Rid:0 Ref_cnt:2 Vrf:52
              Sub NH(label): >>>>>>>>>>>>>>>>>>>>>>>> No Sub next hop

root@nodei9:~# vrfstats --get 52
Vrf: 52
Discards 464618966, Resolves 0, Receives 0, L2 Receives 0, Vrf Translates 464622796, Unknown Unicast Floods 0
Ecmp Composites 0, L2 Mcast Composites 464260202, Fabric Composites 464260202, Encap Composites 0, Evpn Composites 464260202
Udp Tunnels 0, Udp Mpls Tunnels 0, Gre Mpls Tunnels 0, Vxlan Tunnels 0
L2 Encaps 0, Encaps 0
GROs 0, Diags 0
Arp Virtual Proxys 0, Arp Virtual Stitchs 0, Arp Virtual Floods 0, Arp Physical Stitchs 0, Arp Tor Proxys 0, Arp Physical Floods 0

root@nodei9:~# vrfstats --get 52
Vrf: 52
Discards 464822695, Resolves 0, Receives 0, L2 Receives 0, Vrf Translates 464826525, Unknown Unicast Floods 0
Ecmp Composites 0, L2 Mcast Composites 464463931, Fabric Composites 464463931, Encap Composites 0, Evpn Composites 464463931>>>>>>>>>>>>>>>>>EVPN composite next hop is increasing
Udp Tunnels 0, Udp Mpls Tunnels 0, Gre Mpls Tunnels 0, Vxlan Tunnels 0
L2 Encaps 0, Encaps 0
GROs 0, Diags 0
Arp Virtual Proxys 0, Arp Virtual Stitchs 0, Arp Virtual Floods 0, Arp Physical Stitchs 0, Arp Tor Proxys 0, Arp Physical Floods 0

[OpenContrail Admin (ci-admin-f)]

bug update...