Concept Guide

Layer-2 Trac in VLT Domains
In a VLT domain, the MAC address of any host connected to the VLT peers is synchronized between the VLT nodes. In the following
example, VLAN 10 is spanned across three VLT domains.
Figure 127. Layer-2 Trac in VLT Domains
If Host 1 from a VLT domain sends a frame to Host 2 in another VLT domain, the frame can use any link shown to reach Host 2. MAC
synchronization between VLT peers handles the trac ow even if it is hashed and forwarded through the other member of the port-
channel.
Viewing the MAC Synchronization Between VLT Peers
You can use the following commands to verify the MAC synchronization between VLT peers:
VLT-10-PEER-1#show mac-address-table count
MAC Entries for all vlans :
Dynamic Address Count : 1007
Static Address (User-defined) Count : 1
Sticky Address Count : 0
Total Synced Mac from Peer(N): 503
Total MAC Addresses in Use: 1008
VLT-10-PEER-1#show vlt counter mac
Total MAC VLT counters
----------------------
L2 Total MAC-Address Count: 1007
VLT-10-PEER-1#show mac-address-table
Codes: *N - VLT Peer Synced MAC
VlanId Mac Address Type Interface State
10 00:00:4c:54:8b:f6 Dynamic Po 11 Active
10 00:01:e8:95:ec:97 Dynamic Po 33 Active
10 00:01:e8:b3:ba:47 Dynamic Po 33 Active
30 a0:00:a1:00:00:01 Dynamic Po 11 Active
30 a0:00:a1:00:00:02 Dynamic Po 11 Active
30 a0:00:a1:00:00:03 Dynamic Po 11 Active
30 a0:00:a1:00:00:04 Dynamic (N) Po 11 Active
30 a0:00:a1:00:00:05 Dynamic (N) Po 11 Active
30 a0:00:a1:00:00:06 Dynamic (N) Po 11 Active
Virtual Link Trunking (VLT)
947