[c-nsp] SR-TE

Sat Sep 19 00:24:29 EDT 2020

Yes, works!  Thanks Phil and dip for your input.

"autoroute include all" seemed to be the missing ingredient for cli manual srte steering... I'm not sure if it has any downsides at this point, but for what I have, it's working.

Finally got the auto-generated te-tunnel interface to show up in the route table...

also, learned that the auto-created srte interface name is...

srte_c_1_ep_10.20.0.22

which means...

srte color 1 endpoint 10.20.0.22

and now I see traffic hitting that lfib entry

also there's now an interesting additional lfib entry for my endpoint that points to the srte tunnel interface

here's the ce to ce traffic now showing triple mpls tagged via the srte tunnel

ce1#traceroute 1.1.1.2
Type escape sequence to abort.
Tracing the route to 1.1.1.2
VRF info: (vrf in name/id, vrf out name/id)
  1 1.0.0.1 8 msec 2 msec 2 msec
  2 10.20.1.21 [MPLS: Labels 16023/16022/24001 Exp 0] 40 msec 38 msec 38 msec
  3 10.20.1.25 [MPLS: Labels 16022/24001 Exp 0] 41 msec 41 msec 38 msec
  4 10.20.1.9 39 msec 38 msec 42 msec
  5 1.1.1.2 89 msec *  88 msec

Here's my whole config for the Headend SRTE tunnel policy

conf
router ospf 1
 distribute link-state
!
segment-routing
 traffic-eng
  segment-list name my-srte-sidlist-2
   index 1 address ipv4 10.20.0.24
   index 2 address ipv4 10.20.0.23
   index 3 address ipv4 10.20.0.22  
!
  policy my-srte-policy
   binding-sid mpls 100
   color 1 end-point ipv4 10.20.0.22
   autoroute include all
   candidate-paths
    preference 1
     explicit segment-list my-srte-sidlist-2
commit

r10               r30
|                      |
|                      |
r20-----r21-----r22
|                      |
|                      |
r24-------------r23

10.20.0.x - loopback ip's
x = router number

ce r10 is 1.0.0.0/30
ce r30 is 1.1.1.0/30

RP/0/RP0/CPU0:r20#sh route | be Gate
Fri Sep 18 22:53:43.336 CDT
Gateway of last resort is not set

L    10.20.0.20/32 is directly connected, 11:39:19, Loopback0
O    10.20.0.21/32 [110/2] via 10.20.1.2, 11:38:22, GigabitEthernet0/0/0/0
O    10.20.0.22/32 [110/3] via 10.20.0.22, 00:01:38, srte_c_1_ep_10.20.0.22	<<<----------------------
O    10.20.0.23/32 [110/3] via 10.20.1.21, 11:28:18, GigabitEthernet0/0/0/1
O    10.20.0.24/32 [110/2] via 10.20.1.21, 11:28:24, GigabitEthernet0/0/0/1
C    10.20.1.0/30 is directly connected, 11:39:20, GigabitEthernet0/0/0/0
L    10.20.1.1/32 is directly connected, 11:39:20, GigabitEthernet0/0/0/0
O    10.20.1.4/30 [110/2] via 10.20.1.2, 09:36:54, GigabitEthernet0/0/0/0
O    10.20.1.8/30 [110/3] via 10.20.0.22, 00:01:38, srte_c_1_ep_10.20.0.22	<<<----------------------
                  [110/3] via 10.20.1.21, 00:01:38, GigabitEthernet0/0/0/1
C    10.20.1.20/30 is directly connected, 11:39:20, GigabitEthernet0/0/0/1
L    10.20.1.22/32 is directly connected, 11:39:20, GigabitEthernet0/0/0/1
O    10.20.1.24/30 [110/2] via 10.20.1.21, 11:28:23, GigabitEthernet0/0/0/1
L    127.0.0.0/8 [0/0] via 0.0.0.0, 11:39:20

RP/0/RP0/CPU0:r20#sh mpls for
Fri Sep 18 23:04:39.183 CDT
Local  Outgoing    Prefix             Outgoing     Next Hop        Bytes
Label  Label       or ID              Interface                    Switched
------ ----------- ------------------ ------------ --------------- ------------
100    Pop         No ID              srte_c_1_ep_ point2point     0
16021  Pop         SR Pfx (idx 21)    Gi0/0/0/0    10.20.1.2       0
16022  16022       SR Pfx (idx 22)    Gi0/0/0/0    10.20.1.2       1028
16023  16023       SR Pfx (idx 23)    Gi0/0/0/1    10.20.1.21      0
16024  Pop         SR Pfx (idx 24)    Gi0/0/0/1    10.20.1.21      0
24000  Pop         SR Adj (idx 0)     Gi0/0/0/0    10.20.1.2       0
24001  Aggregate   one: Per-VRF Aggr[V]   \
                                      one                          1744516
24002  Pop         SR Adj (idx 0)     Gi0/0/0/1    10.20.1.21      0
24004  16023       SR TE: 22 [TE-INT]  Gi0/0/0/1    10.20.1.21      3648	<<<----------------------
24011  Pop         10.20.0.22/32      srte_c_1_ep_ 10.20.0.22      3936	<<<----------------------

the L3VPN cef entry on the headend for the ce traffic is....

RP/0/RP0/CPU0:r20#sh cef vrf one 1.1.1.0/30
Fri Sep 18 23:05:33.909 CDT
1.1.1.0/30, version 5, internal 0x5000001 0x0 (ptr 0xdef99e4) [1], 0x0 (0xe0bcc68), 0xa08 (0xe8a2368)
 Updated Sep 18 11:25:40.565
 Prefix Len 30, traffic index 0, precedence n/a, priority 3
   via 10.20.0.22/32, 3 dependencies, recursive [flags 0x6000]
    path-idx 0 NHID 0x0 [0xd2cc890 0x0]
    recursion-via-/32
    next hop VRF - 'default', table - 0xe0000000
    next hop 10.20.0.22/32 via 24011/0/21
     next hop 10.20.0.22/32 srte_c_1_ep_ labels imposed {ImplNull 24001}	<<<----------------------

- aaron