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Disjoint Layer 2 networks with same upstream Vlans

I have an issue,


There are 3 different networks attached to a UCS via 3 different switches.

1st network is the Main LAN network

2nd Network is the Backup LAN network

3rd Network is the DMZ network

I have configured all the present vlans configured on the UCS to go up the Main LAN network. and i used the 'VLAN groups' feature to isolate the Main LAN traffic to 2 uplinks on each Fabric-interconnect. 

The other two networks are both on vlan 1. Is there any workaround to enable traffic to work towards them on separated uplinks?



VIP Green

I assume you are aware of the

I assume you are aware of the following caveat:


Default VLAN 1 Cannot Be Configured Explicitly on an Uplink Ethernet Port or Port Channel

Cisco UCS Manager implicitly assigns default VLAN 1 to all uplink ports and port channels. Even if you do

not configure any other VLANs, Cisco UCS uses default VLAN 1 to handle data traffic for all uplink ports

and port channels.

p 309 of


Overlapping VLANs Are Not Supported

Cisco UCS does not support overlapping VLANs in disjoint L2 networks. You must ensure that each VLAN

only connects to one upstream disjoint L2 Domain.

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