[c-nsp] (BGP) BFD on XR in vrf on sub-interface of bundle-ether interface

[christoffer at netravnen.de]

c-nsp,

Anyone having tried running (BGP) BFD on XR in vrf on sub-interface of
bundle-ether interface with success? Have tried looking through
documentation at Cisco.com with no luck so far.

Currently trying to get a session up with an non-cisco device on the
other end. No avail. Luck is close to up.
Have tried reading the Cisco Documentation from 4.2 release concerning
the restrictions to BFD mentioned. But I cannot get around to be wiser
if the restrictions applies to the below mentioned situation or not. :???:



[Cisco XR <=> Cisco SW (L2) <=> Juniper SW (L2) <=> Arista SW (L3)]
[   \            /    \             /        \           /        ]
[   trunk    trunk    trunk      trunk     access    access       ]
[     \        /        \         /            \       /          ]
[     #Vlan tagged#     #Vlan tagged#          #untagged#         ]

BFD is tried configured between XR and Arista SW.

  * Cisco XR <=> Cisco SW (L2) : trunk interface (LAG group)
  * Cisco SW (L2) <=> Juniper SW (L2) : trunk interface
  * Juniper SW (L2) <=> Arista SW (L3) : access interface

  § same Vlan tag is carried on traffic between Cisco XR <=> Juniper SW.
    Juniper SW pops vlan tag before forwarding traffic to Arista SW.

Using "monitor traffic interface(...)matching "udp && (port 49152 ||
port 3784)" looking for traversing BFD packets on Juniper SW (L2)...
Returns an empty output. No packet(s) matched.



Configuration Example Snippet from XR:

bfd
 interface Bundle-Ether500.600
  no echo
 !
!
interface Bundle-Ether500.600
 vrf RED
 ipv4 mtu 1500
 ipv4 address 10.10.10.9 255.255.255.252
 encapsulation dot1q 600
!
router bgp 65000
 vrf RED
  neighbor 10.10.10.10
   remote-as 65001
   bfd fast-detect
   bfd multiplier 3
   bfd minimum-interval 3000
  !
 !
!
interface Bundle-Ether500
 mtu 9000
 bundle minimum-active links 1
!
interface Te0/0/0/0
 bundle id 500 mode active
!
interface Te0/0/1/3
 bundle id 500 mode active
!


RP/0/RSP1/CPU0:XR#sh conf run int Bundle-Ether500.600
I/f: Bundle-Ether500.600, Location: 0/RSP1/CPU0
Dest: 10.10.10.10
Src: 10.10.10.9
 State: DOWN for 0d:1h:0m:0s, number of times UP: 0
 Session type: SW/V4/SH/BL
Received parameters:
 Version: 0, desired tx interval: 0 ms, required rx interval: 0 ms
 Required echo rx interval: 0 ms, multiplier: 0, diag: None
 My discr: 0, your discr: 0, H/D/F/P/C/A: 0/0/0/0/0/0
Transmitted parameters:
 Version: 0, desired tx interval: 0 ms, required rx interval: 0 ms
 Required echo rx interval: 0 ms, multiplier: 0, diag: None
 My discr: 0, your discr: 0, H/D/F/P/C/A: 0/0/0/0/0/0
Timer Values:
 Local negotiated async tx interval: 0 ms
 Remote negotiated async tx interval: 0 s
 Desired echo tx interval: 0 s, local negotiated echo tx interval: 0 ms
 Echo detection time: 0 ms, async detection time: 0 ms
Label:
 Internal label: 289033/0x46909
Local Stats:
 Intervals between async packets:
   Tx: Number of intervals=0, min=0 s, max=0 s, avg=0 s
       Last packet transmitted 0 s ago
   Rx: Number of intervals=0, min=0 s, max=0 s, avg=0 s
       Last packet received 0 s ago
 Intervals between echo packets:
   Tx: Number of intervals=0, min=0 s, max=0 s, avg=0 s
       Last packet transmitted 0 s ago
   Rx: Number of intervals=0, min=0 s, max=0 s, avg=0 s
       Last packet received 0 s ago
 Latency of echo packets (time between tx and rx):
   Number of packets: 0, min=0 ms, max=0 ms, avg=0 ms
MP download state: BFD_MP_DOWNLOAD_NO_LC
State change time: Jun 28 14:14:14.147
Session owner information:
                            Desired               Adjusted
  Client               Interval   Multiplier Interval   Multiplier
  -------------------- --------------------- ---------------------
  bgp-default          3 s        3          3 s        3


RP/0/RSP1/CPU0:XR#sh ver | i Cisco IOS XR Software
Cisco IOS XR Software, Version 5.3.4[Default]


RP/0/RSP1/CPU0:XR#show bfd counters packet
	---empty_output---