Description Behavior at Peer Up Behavior During Run Time Action to Takeinformation, refer to the ReleaseNotes for this release.VLT LAG ID is not configured onone VLT peerA syslog error message isgenerated. The peer with theVLT configured remains active.A syslog error message isgenerated. The peer with theVLT configured remains active.Verify the VLT LAG ID isconfigured correctly on both VLTpeers.VLT LAG ID mismatch The VLT port channel is broughtdown.A syslog error message isgenerated.The VLT port channel is broughtdown.A syslog error message isgenerated.Perform a mismatch check afterthe VLT peer is established.Reconfiguring Stacked Switches as VLTTo convert switches that have been stacked to VLT peers, use the following procedure.1 Remove the current configuration from the switches. You will need to split the configuration up for each switch.2 Copy the files to the flash memory of the appropriate switch.3 Copy the files on the flash drive to the startup-config.4 Reset the stacking ports to user ports for both switches.5 Reload the stack and confirm the new configurations have been applied.6 On the Secondary switch (stack-unit 2), enter the command stack-unit 2 renumber 1.7 Confirm the reload query.8 After reloading, confirm that VLT is enabled.9 Confirm that the management ports are interconnected or connected to a switch that can transfer Heartbeat information.Specifying VLT Nodes in a PVLANYou can configure VLT peer nodes in a private VLAN (PVLAN). VLT enables redundancy without the implementation of Spanning TreeProtocol (STP), and provides a loop-free network with optimal bandwidth utilization.Because the VLT LAG interfaces are terminated on two different nodes, PVLAN configuration of VLT VLANs and VLT LAGs aresymmetrical and identical on both the VLT peers. PVLANs provide Layer 2 isolation between ports within the same VLAN. A PVLANpartitions a traditional VLAN into sub-domains identified by a primary and secondary VLAN pair. With VLT being a Layer 2 redundancymechanism, support for configuration of VLT nodes in a PVLAN enables Layer 2 security functionalities. To achieve maximum VLT resiliency,you should configure the PVLAN IDs and mappings to be identical on both the VLT peer nodes.The association of PVLAN with the VLT LAG must also be identical. After the VLT LAG is configured to be a member of either the primaryor secondary PVLAN (which is associated with the primary), ICL becomes an automatic member of that PVLAN on both switches. Thisassociation helps the PVLAN data flow received on one VLT peer for a VLT LAG to be transmitted on that VLT LAG from the peer.You can associate either a VLT VLAN or a VLT LAG to a PVLAN. First configure the VLT interconnect (VLTi) or a VLT LAG by using thepeer-link port-channel id-number command or the VLT VLAN by using the peer-link port-channel id-numberpeer-down-vlan vlan interface number command and the switchport command. After you specify the VLTi link and VLTLAGs, you can associate the same port channel or LAG bundle that is a part of a VLT to a PVLAN by using the interface interfaceand switchport mode private-vlan commands.When a VLTi port in trunk mode is a member of symmetric VLT PVLANs, the PVLAN packets are forwarded only if the PVLAN settings ofboth the VLT nodes are identical. You can configure the VLTi in trunk mode to be a member of non-VLT PVLANs if the VLTi is configuredon both the peers. MAC address synchronization is performed for VLT PVLANs across peers in a VLT domain.Virtual Link Trunking (VLT) 967
