Connectivity Guide

VLT interconnect
A VLT interconnect (VLTi) synchronizes states between VLT peers. OS10 automatically adds VLTi ports to VLANs spanned across VLT
peers and does not add VLTi ports to VLANs congured on only one peer.
• VLAN ID 4094 is reserved as an internal control VLAN for the VLT domain, and it is not user congurable.
• The VLTi synchronizes L2 and L3 control-plane information across the two nodes. The VLTi is used for data trac only when there is a
link failure that requires VLTi to reach the nal destination.
• Trac with an unknown destination MAC address, multicast, or broadcast trac can cause ooding across the VLTi.
• MAC, ARP, IPv6 neighbors that are learned over VLANs on VLT peer nodes synchronize using VLTi.
• LLDP, ow control, port monitoring, and jumbo frame features are supported on a VLTi.
Congure VLT
Verify that both VLT peer devices are running the same OS version. For VRRP operation, congure VRRP groups and L3 routing on each
VLT peer.
Congure the following settings on each VLT peer device separately.
1 (Optional) To prevent loops in VLT domain, enable the STP globally using the spanning-tree mode {rstp | rapid-pvst}
command.
2 Create a VLT domain by conguring the same domain ID on each peer using the vlt-domain command.
3 (Optional) To override the default VLT primary election mechanism based on the system MAC addresses of the VLT nodes, congure
a VLT node priority for each of the VLT nodes using the primary-priority command. Enter a lower priority value for the desired
primary VLT peer and a higher priority value for the desired secondary VLT peer.
4 Congure the VLTi interfaces on each peer using the discovery-interface command. After you congure both sides of the
VLTi, the primary and secondary roles in the VLT domain are automatically assigned if primary priority is not congured.
5 (Optional) Manually recongure the default VLT MAC address. Congure the VLT MAC address in both VLT peers.
6 (Optional) Congure a time interval to delay bringing up VLT ports after reload or when VLTi come up after failure.
7 Congure the VLT backup link the heartbeat use with the backup destination {ip-address | ipv6 ipv6–address }
[vrf management] [interval interval-time] command.
8 Congure VLT port-channels between VLT peers and an attached device using the vlt-port-channel command. Assign the
same VLT port-channel ID from 1 to 1024 to interfaces on dierent peers that you bundle together. The peer interfaces appear as a
single VLT LAG to downstream devices.
9 Connect peer devices in a VLT domain to an attached access device or server.
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Virtual Link Trunking