02-13-2020 12:54 PM - edited 02-13-2020 12:59 PM
I currently have a Nexus 7000 (n7000-s2-dk9.6.2.16.bin) that is trying to communicate with an ASR 1001-x (v03.16.07b.S). Both IPv4 and IPv6 are configured on the two routers. OSPFv2 handshakes without issues whereas OSPFv3 gets stuck on the Nexus in the EXSTART state (constantly cycles back to INIT, etc).
ASR1001-x
interface TenGigabitEthernet0/0/0.116
encapsulation dot1Q 116
ip address xxx.xxx.88.211 255.255.255.240
standby version 2
standby 116 ip xxx.xxx.88.209
standby 116 authentication md5 key-string xxxxxxxxxx
ipv6 address FE80::116:102 link-local
ipv6 address xxxx:xxxx:130:1::102/64
ipv6 enable
ospfv3 101 priority 25
ospfv3 101 ipv6 area 0
router ospf 101
log-adjacency-changes detail
network xxx.xx.88.208 0.0.0.15 area 0
network xxx.xxx.103.24 0.0.0.7 area 0
network xxx.xxx.103.251 0.0.0.0 area 0
router ospfv3 101
address-family ipv6 unicast
log-adjacency-changes detail
exit-address-family
NEXUS7000
interface Vlan116
vrf member tower_net
ip address xxx.xxx.88.219/28
ipv6 address xxxx:xxxx:130:1::1eaf:101/64
ipv6 link-local fe80::116:199
ip ospf cost 10
ip router ospf 101 area 0.0.0.0
ospfv3 cost 10
no ospfv3 passive-interface
ipv6 router ospfv3 101 area 0.0.0.0
no shutdown
router ospf 101
vrf tower_net
network xxx.xxx.88.208/28 area 0.0.0.0
network xxx.xxx.100.0/24 area 0.0.0.0
network xxx.xxx.103.252/32 area 0.0.0.0
log-adjacency-changes detail
router ospfv3 101
vrf tower_net
log-adjacency-changes detail
address-family ipv6 unicast
Looking at the states for both OSPFv2 and OSPFv3 on the nexus, we get:
core-sv7-nexus1# sho ip ospf neighbors vrf tower_net
OSPF Process ID 101 VRF tower_net
Total number of neighbors: 3
Neighbor ID Pri State Up Time Address Interface
xxx.xxx.20.10 1 FULL/DROTHER 22w0d xxx.xxx.88.218 Vlan116
xxx.xxx.103.250 1 FULL/BDR 34w1d xxx.xxx.88.210 Vlan116
xxx.xxx.103.251 1 FULL/DROTHER 33w0d xxx.xxx.88.211 Vlan116
core-sv7-nexus1# sho ospfv3 vrf tower_net nei
OSPFv3 Process ID 101 VRF tower_net
Total number of neighbors: 3
Neighbor ID Pri State Up Time Interface ID Interface
xxx.xxx.103.248 1 TWOWAY/DROTHER 00:02:28 7 Vlan116
Neighbor address fe80::116:901
xxx.xxx.103.250 25 EXSTART/BDR 00:02:37 27 Vlan116
Neighbor address fe80::116:101
xxx.xxx.103.251 25 EXSTART/DR 00:02:28 24 Vlan116
Neighbor address fe80::116:102
Have verified with both IPv4 and IPv6 that my MTUs are not mismatched (tried using ignore-mtu as well with no change). Looking at the logs on a particular handshake (its the same for all of them, just focusing on one for clarity) I get the following repeating over and over when talking to the non-BD/BDRs:
2020 Feb 7 17:30:09 core-sv7-nexus1 %OSPFV3-5-NBRSTATE: ospfv3-101 [25249] Process 101, Nbr xxx.xxx.103.250 on Vlan116 from EXSTART to INIT, ONEWAYRCVD
2020 Feb 7 17:31:16 core-sv7-nexus1 %OSPFV3-5-NBRSTATE: ospfv3-101 [25249] Process 101, Nbr xxx.xxx.103.250 on Vlan116 from INIT to EXSTART, ADJOK
2020 Feb 7 17:33:19 core-sv7-nexus1 %OSPFV3-5-NBRSTATE: ospfv3-101 [25249] Process 101, Nbr xxx.xxx.103.250 on Vlan116 from EXSTART to INIT, ONEWAYRCVD
and talking to the DR/BDR I get the following (repeating over and over):
2020 Feb 7 17:30:09 core-nexus1 %OSPFV3-5-NBRSTATE: ospfv3-101 [25249] Process 101, Nbr xxx.xxx.103.248 on Vlan116 from TWOWAY to TWOWAY, ADJOK
2020 Feb 7 17:30:12 core-nexus1 %OSPFV3-5-NBRSTATE: ospfv3-101 [25249] Process 101, Nbr xxx.xxx.103.248 on Vlan116 from TWOWAY to EXSTART, ADJOK
2020 Feb 7 17:31:18 core-nexus1 %OSPFV3-5-NBRSTATE: ospfv3-101 [25249] Process 101, Nbr xxx.xxx.103.248 on Vlan116 from EXSTART to TWOWAY, ADJOK
After a couple days, I'm completely lost. At this point figured I'd ask around to see if anyone else knows or has seen this with OSPFv3...
12-19-2020 05:08 AM
were u able to find a fix?
12-19-2020 06:45 AM
Hello,
are you having this problem ? Have a look at the link below for troubleshooting...
12-19-2020 10:59 AM - edited 12-19-2020 11:00 AM
Hello
First thought with exstart is MTU however is you have tried to negate that,So have you try changing the nework type to point-to-point?
Also can you post the output of debug?
debug ip ospfv6 adj
12-21-2020 08:19 PM
I did configure ip ospf mtu-ignore ,but no luck.
MTU is 1500 on both sides.
2020 Dec 21 19:21:23 %OSPF-5-NBRSTATE: ospf- [1746] Process , Nbr 10.x.x.x on Ethernet1/3 from INIT to EXSTART, ADJOK
2020 Dec 21 19:23:27 %OSPF-5-NBRSTATE: ospf- [1746] Process , Nbr 10.x.x.x on Ethernet1/3 from EXSTART to INIT, ONEWAYRCVD
2020 Dec 21 19:24:24 %OSPF-5-NBRSTATE: ospf-[1746] Process , Nbr 10.x.x.x on Ethernet1/3 from INIT to EXSTART, ADJOK
thinking to roll cable from rx to tx
12-22-2020 12:06 AM
- Check if these info's can also be useful :
M.
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