ISIS routes not being advertised into OSPF

[Anonymous]

Hi,

Must be missing some configuration but can’t see it.

In summary I’m trying to redistribute ISIS routes into OSPF with this command:

router ospf
   redistribute isis
   redistribute isis enable
exit
ip ospf apply redistribute isis

There is basically one P2P link between a VSP and S8 that has a full adjacency and is sharing the OSPF routing table. I can ping anything from the VSP on the S8 network, so thats all working well.

The IP addresses I can ping from the S8 to the VSP are only the OSPF networks I have configured on the VSP, basically I can not ping anything that’s in the ISIS routing table that includes the CLIP’s and Mgmt CLIP.

Here is the view of the ISIS routing table on the VSP:

Por-DC1-Core1:1#% show ip route protocol isis
************************************************************************************
                Command Execution Time: Thu Dec 03 23:07:49 2020 GMT
************************************************************************************
=====================================================================================================
                                       IP Route - GlobalRouter
=====================================================================================================
                                                     NH                      INTER
DST             MASK            NEXT                 VRF/ISID         COST   FACE     PROT AGE TYPE PRF
-----------------------------------------------------------------------------------------------------
172.22.0.212    255.255.255.255 Por-DC1-Core2        GlobalRouter     10     4051     ISIS 0   IBS  7
172.22.0.221    255.255.255.255 Por-DC2-Core1        GlobalRouter     10     4051     ISIS 0   IBS  7
172.22.0.222    255.255.255.255 Por-DC2-Core2        GlobalRouter     20     4051     ISIS 0   IBS  7
172.22.1.212    255.255.255.252 Por-DC2-Core1        GlobalRouter     10     4051     ISIS 0   IBS  7
172.22.1.220    255.255.255.252 Por-DC1-Core2        GlobalRouter     10     4051     ISIS 0   IBS  7
172.22.1.244    255.255.255.252 Por-DC1-Core2        GlobalRouter     10     4051     ISIS 0   IBS  7
192.168.200.212 255.255.255.255 Por-DC1-Core2        GlobalRouter     10     4051     ISIS 0   IBS  7
192.168.200.221 255.255.255.255 Por-DC2-Core1        GlobalRouter     10     4051     ISIS 0   IBS  7
192.168.200.222 255.255.255.255 Por-DC2-Core2        GlobalRouter     20     4051     ISIS 0   IBS  7

The VLAN being used to connect the VSP and S8 is 3901, on the S8 you can see I’m only learning OSPF interfaces that I have configured on the VSP’s, none of the ISIS routes are being learnt?

PorLANCore01(su)->show ip route ospf |find vlan.0.3901
O      172.22.1.208/30     [110/20]     via       172.22.1.201     vlan.0.3901              55m26s
O      172.22.1.212/30     [110/30]     via       172.22.1.201     vlan.0.3901              55m26s
O      172.22.1.216/30     [110/20]     via       172.22.1.201     vlan.0.3901              55m26s
O      172.22.1.220/30     [110/30]     via       172.22.1.201     vlan.0.3901              55m26s

Here is a bit more of a snapshot of the VSP config

interface GigabitEthernet 1/16
   encapsulation dot1q
exit

router isis
   spbm 1
   spbm 1 nick-name d.02.11
   spbm 1 b-vid 4051-4052 primary 4051
   spbm 1 multicast enable
   spbm 1 ip enable
   spbm 1 smlt-virtual-bmac 00:00:84:04:01:01
   spbm 1 smlt-peer-system-id 020d.0020.0221
exit

mlt 501 enable name "NNI-QSFP-DC1"
mlt 501 member 1/18
mlt 501 encapsulation dot1q
mlt 503 enable name "NNI-DC1-DC2"
mlt 503 member 1/17
mlt 503 encapsulation dot1q

ip prefix-list "suppressIST" 172.22.1.240/30 id 1 ge 29 le 29
ip prefix-list "suppressIST" 172.22.1.244/30 id 1 ge 29 le 29

vlan members remove 1 1/1-1/18 portmember

vlan create 3401 name "OSP P2P DC1-CR1 to DC1-CR2" type port-mstprstp 0
vlan i-sid 3401 123401
interface Vlan 3401
   ip address 172.22.1.209 255.255.255.252 2
   ip ospf enable
exit
vlan create 3403 name "OSP P2P DC-CR1 to DC2-CR1" type port-mstprstp 0
vlan i-sid 3403 123403
interface Vlan 3403
   ip address 172.22.1.217 255.255.255.252 3
   ip ospf enable
exit
vlan create 3901 name "OSPF P2P Legacy to CR1" type port-mstprstp 0
vlan members 3901 1/16 portmember
vlan i-sid 3901 123901
interface Vlan 3901
   ip address 172.22.1.201 255.255.255.252 1
   ip ospf enable
exit
vlan create 4051 type spbm-bvlan
vlan create 4052 type spbm-bvlan
vlan create 4053 type port-mstprstp 0
vlan i-sid 4053 124053
interface Vlan 4053
   ip address 172.22.1.241 255.255.255.252 0
exit
mgmt clip vrf GlobalRouter
   ip address 192.168.200.211/32
   enable
exit
virtual-ist  peer-ip 172.22.1.242 vlan 4053
interface mlt 501
   isis
   isis spbm 1
   isis enable
exit
interface mlt 503
   isis
   isis spbm 1
   isis enable
exit
interface GigabitEthernet 1/16
   default-vlan-id 0
   no shutdown
exit
interface GigabitEthernet 1/17
   default-vlan-id 0
   no shutdown
   no spanning-tree mstp  force-port-state enable
   no spanning-tree mstp msti 62 force-port-state enable
exit
interface GigabitEthernet 1/18
   default-vlan-id 0
   no shutdown
   no spanning-tree mstp  force-port-state enable
   no spanning-tree mstp msti 62 force-port-state enable
exit
route-map "suppressIST" 1
   no permit
   enable
   match network "suppressIST"
   set metric-type type2
   set nssa-pbit enable
exit
route-map "suppressIST" 2
   permit
   enable
   match protocol local
exit
ip route 0.0.0.0 0.0.0.0 172.22.1.202 weight 1
interface loopback 1
   ip address 1 172.22.0.111/255.255.255.255
exit
router isis
   sys-name "Por-DC1-Core1"
   is-type l1
   system-id 020d.0020.0211
   manual-area 49.0001
exit
router isis enable

cfm spbm mepid 811
cfm spbm enable

router ospf enable
router ospf
   router-id 172.22.0.211
exit
router ospf
   redistribute isis
   redistribute isis enable
exit
router isis
   redistribute direct
   redistribute direct route-map "suppressIST"
   redistribute direct enable
exit
end
ip ospf apply redistribute isis
isis apply redistribute direct

Appreciate any help in advance.

Many thanks

[Anonymous]

Hi Mig,

Thanks for posting.

These are both in area 0.0.0.0. The reason is the network is migrating from S8’s to VSP’s, so the area needs to stay the same for when the S8’s disappear and as subnets get moved across.

The outputs of those commands are too large to post here, maybe 100’s or 1000’s of entries.

Only one with a subset of data is as follows, the first adjacency is the one to the S8. The other two are to other VSP switches.

Por-DC1-Core1:1#% show ip ospf neighbor
************************************************************************************
                Command Execution Time: Thu Dec 03 23:30:41 2020 GMT
************************************************************************************

====================================================================================================
                         OSPF Neighbors - GlobalRouter
====================================================================================================
INTERFACE       NBRROUTERID     NBRIPADDR       PRIO    STATE    RTXQLEN PERM TTL
----------------------------------------------------------------------------------------------------
172.22.1.201    0.119.255.141   172.22.1.202    1    Full     0       Dyn   34
172.22.1.217    172.22.0.221    172.22.1.218    1    Full     0       Dyn   36
172.22.1.209    172.22.0.212    172.22.1.210    1    Full     0       Dyn   36

Show ip ecmp doesn’t seem to take.

Is there anything in the routing table that you specifically need to see, suffice to say there is a lot of routes being shared via OSPF between the S8 and VSP.

Appreciate you might need more context or detail, so let me know if you need anything else.

Cheers,

Martin

[Miguel-Angel_RO]

Martin,

Shouldn’t you enable asbr on the VSP and assign the area corresponding to the S8?

router ospf

as-boundary-router enable

area 0.0.0.1

exit

As debug commands, please share:

show ip route

show ip route alternative

show ip route proto ospf

show ip ospf ase

show ip ecmp

show ip ospf neighbor

Mig