A small example about the “private-vlan synchronize” command in MST configuration mode (vlan 100 = primary VLAN, vlan 101 = secondary (isolated) VLAN):
n5k-1(config-mst)# show Pending MST Configuration Name [test] Revision 0 Instances configured 3 Instance Vlans mapped -------- --------------------------------------------------------------------- 0 1000-4094 1 1-100 2 101-999 ------------------------------------------------------------------------------- These secondary vlans are not mapped to the same instance as their primary: -> 101 n5k-1(config-mst)# private-vlan synchronize n5k-1(config-mst)# show Pending MST Configuration Name [test] Revision 0 Instances configured 3 Instance Vlans mapped -------- --------------------------------------------------------------------- 0 1000-4094 1 1-101 2 102-999 -------------------------------------------------------------------------------
As you see, it modified the MST instance configuration so that the secondary VLAN (101) was moved to the same MST instance as the primary VLAN.