Hi, I have sorted the issue out. VLT switches didn't like the design with Integrated Routing and Bridging feature. When reconfigured Cisco router, and vlt peers to use static LAG everything is working fine. Best Regards, Mateusz
Hi, I am trying to set up VLT domain which will connect downstream to several N-series Switches and upstream to Cisco Router and I am experiencing unusual behavior. S4048-ON are running 9.10(0.1) software So VLT itself work but OSPF adjacency with Cisco router will not form when 2 VLT peers are up. As soon as I power off the second peer the ospf adjacency is forming instantly. Also when 2 peers are alive one of them is very unresponsive (drops packets, and if not the latency is around 500ms), again, when I power off one peer device (doesn't matter which one) everything works just fine. Is there something wrong in my config or is it a software bug ? PS Edge switches are connected to Te1/1 - 1/3. Router is connected to Te1/45 and VLTi is configured on Te1/47 and Te1/48... on both VLT peers Configs for reference: 1st VLT peer:  T1-CSW#sh runCurrent Configuration ...! Version 9.10(0.1)!boot system stack-unit 1 primary system: A:boot system stack-unit 1 secondary system: B:boot system stack-unit 1 default system: A:!hostname T1-CSW!protocol lldp!redundancy auto-synchronize full![edit]lacp system-priority 1!protocol spanning-tree rstp no disable bridge-priority 0!!vlt domain 100 peer-link port-channel 100 back-up destination 10.10.254.2 primary-priority 10!stack-unit 1 provision S4048-ON!interface TenGigabitEthernet 1/1 no ip address! port-channel-protocol LACP port-channel 1 mode active no shutdown!interface TenGigabitEthernet 1/2 no ip address! port-channel-protocol LACP port-channel 2 mode active no shutdown!interface TenGigabitEthernet 1/3 no ip address! port-channel-protocol LACP port-channel 3 mode active no shutdown![edit]!interface TenGigabitEthernet 1/45 no ip address switchport no shutdown!interface TenGigabitEthernet 1/46 no ip address shutdown!interface TenGigabitEthernet 1/47 no ip address no shutdown!interface TenGigabitEthernet 1/48 no ip address no shutdown![edit]!interface Port-channel 1 no ip address switchport vlt-peer-lag port-channel 1 no shutdown!interface Port-channel 2 no ip address switchport vlt-peer-lag port-channel 2 no shutdown!interface Port-channel 3 no ip address switchport vlt-peer-lag port-channel 3 no shutdown!interface Port-channel 100 no ip address channel-member TenGigabitEthernet 1/47-1/48 no shutdown!interface Vlan 1!untagged Port-channel 100!interface Vlan 2 ip address 192.0.0.1/16 tagged Port-channel 1-3 no shutdown!interface Vlan 3 ip address 172.0.0.1/16 tagged Port-channel 1-3 no shutdown!interface Vlan 4 ip address 10.0.1.1/24 tagged Port-channel 1 no shutdown!interface Vlan 5 no ip address tagged Port-channel 1 no shutdown!interface Vlan 8 ip address 10.10.8.1/23 tagged TenGigabitEthernet 1/17 tagged Port-channel 1-3 no shutdown!interface Vlan 40 ip address 10.10.40.1/22 tagged Port-channel 1-3 no shutdown!interface Vlan 98 ip address 10.10.90.2/24 no shutdown!interface Vlan 240 ip address 10.10.240.1/22 tagged Port-channel 1-3 no shutdown!interface Vlan 997 no ip address tagged Port-channel 1-3 no shutdown!interface Vlan 999 ip address 10.255.10.10/24 tagged TenGigabitEthernet 1/45 tagged Port-channel 45 no shutdown!interface Vlan 1001 ip address 10.10.254.1/24 no shutdown!router ospf 1 router-id 10.255.10.10 network 10.10.8.0/23 area 0 network 10.255.10.0/24 area 0 passive-interface default no passive-interface Vlan 999![edit]!end -----------------------------------------------------------  2nd VLT Peer:  T2-CSW#sh runCurrent Configuration ...! Version 9.10(0.1)!boot system stack-unit 1 primary system: A:boot system stack-unit 1 secondary system: B:boot system stack-unit 1 default system: A:!logging monitor informational!hostname T2-CSW!protocol lldp!redundancy auto-synchronize full![edit]lacp system-priority 1!protocol spanning-tree rstp no disable bridge-priority 4096!vlt domain 100 peer-link port-channel 100 back-up destination 10.10.254.1 primary-priority 20!stack-unit 1 provision S4048-ON!interface TenGigabitEthernet 1/1 no ip address! port-channel-protocol LACP port-channel 1 mode active no shutdown!interface TenGigabitEthernet 1/2 no ip address! port-channel-protocol LACP port-channel 2 mode active no shutdown!interface TenGigabitEthernet 1/3 no ip address! port-channel-protocol LACP port-channel 3 mode active no shutdown![edit]!interface TenGigabitEthernet 1/45 no ip address switchport no shutdown!interface TenGigabitEthernet 1/46 no ip address no shutdown!interface TenGigabitEthernet 1/47 no ip address no shutdown!interface TenGigabitEthernet 1/48 no ip address no shutdown![edit]!interface Port-channel 1 no ip address switchport vlt-peer-lag port-channel 1 no shutdown!interface Port-channel 2 no ip address switchport vlt-peer-lag port-channel 2 no shutdown!interface Port-channel 3 no ip address switchport vlt-peer-lag port-channel 3 no shutdown!interface Port-channel 10 no ip address no shutdown!interface Port-channel 100 no ip address channel-member TenGigabitEthernet 1/47-1/48 no shutdown!interface Vlan 1!untagged Port-channel 100!interface Vlan 2 ip address 192.0.0.2/16 tagged Port-channel 1-3 no shutdown!interface Vlan 3 ip address 172.0.0.2/16 tagged Port-channel 1-3 no shutdown!interface Vlan 4 ip address 10.0.1.2/24 tagged Port-channel 1 no shutdown!interface Vlan 5 no ip address tagged Port-channel 1 no shutdown!interface Vlan 8 ip address 10.10.8.2/23 tagged TenGigabitEthernet 1/17 tagged Port-channel 1-3 no shutdown!interface Vlan 40 ip address 10.10.40.2/22 tagged Port-channel 1-3 no shutdown!interface Vlan 98 ip address 10.10.90.1/24 no shutdown!interface Vlan 240 ip address 10.10.240.2/22 tagged Port-channel 1-3 no shutdown!interface Vlan 997 no ip address tagged TenGigabitEthernet 1/45 tagged Port-channel 1-3 no shutdown!interface Vlan 999 ip address 10.255.10.11/24 tagged TenGigabitEthernet 1/45 no shutdown!interface Vlan 1001 ip address 10.10.254.2/24 no shutdown!router ospf 1 router-id 10.255.10.11 network 10.10.8.0/23 area 0 network 10.255.10.0/24 area 0 passive-interface default no passive-interface Vlan 999!ip ssh server enableip ssh server version 2!line console 0 logging synchronous level 2 limit 20line vty 0line vty 1line vty 2line vty 3line vty 4line vty 5line vty 6line vty 7line vty 8line vty 9!reload-type boot-type normal-reload config-scr-download enable!endT2-CSW#  --------------------------------------------------------------  Cisco Router: Router#sh runBuilding configuration... Current configuration : 2042 bytes!version 12.4service timestamps debug datetime msecservice timestamps log datetime msecno service password-encryption!hostname Router!boot-start-markerboot-end-marker!!no aaa new-model!resource policy!ip subnet-zeroip cef!voice-card 0 no dspfarm!bridge irb!!!interface Loopback0 ip address 8.8.8.8 255.255.255.255!interface GigabitEthernet0/0 mtu 1500 no ip address duplex auto speed auto media-type rj45 negotiation auto!interface GigabitEthernet0/0.999 encapsulation dot1Q 999 no snmp trap link-status bridge-group 255 bridge-group 255 spanning-disabled!interface GigabitEthernet0/1 mtu 1500 no ip address duplex auto speed auto media-type rj45 negotiation auto!interface GigabitEthernet0/1.999 encapsulation dot1Q 999 no snmp trap link-status bridge-group 255 bridge-group 255 spanning-disabled!interface BVI255 ip address 10.255.10.2 255.255.255.0 ip ospf 1 area 0!router ospf 1 router-id 10.255.10.2 log-adjacency-changes redistribute connected subnets network 10.0.0.0 0.0.0.255 area 0!ip classless![edit]!control-plane!bridge 253 route ipbridge 255 route ip![edit]!end 
S4048-ON VLT issue (connecting to Cisco OSPF Router using IRB)