Cisco Support Community
Community Member

Connection fabric interconnects to different switches

We have a seperate physical network for our DMZ and a seperate physical network for some other isolated hosts.  Most of these machines in the two environments are virtual machines residing on 2U rack server machines running ESXi.  We are getting some UCS to replace these rack servers.  We'll have one set of fabric interconnects (6296's) and a couple chassis's with blades for ESXi.  My question is can I take uplink ehternet ports and connect them to the two different network environments.  For example, could I take ports 37 and 38 on both interconnects and connect them to the switches in our DMZ network and port 39 and 40 on both interconnects and connect them to swithces on the other network.  Would I be able to setup the ESXi server to connect to vlan's in both of the seperate networks as long as the trunks have the vlans on them?

Cisco Employee

Re: Connection fabric interconnects to different switches

You're talking about Disjoint Layer 2 Uplinks  - and Yes, UCS is  perfectly adapted to support this.  You will use the Uplink Manager  to assign certain VLANs to certain uplinks (DMZ VLANS to only DMZ  uplinks etc). 

Each vNIC you present to your service profiles/hosts  can only be pinned to one uplink set - so if you have a single or set of  DMZ VLANs, they would need to be assigned to a single vNIC within your  service profile.  You can still have non-DMZ VLANs accessed by the same  host, as long as they're assigned to a separate vNIC. 

Ex.  ESX-Service-Profile

vNIC0 - Managment VLANs

vNIC1 - VMotion VLANs


vNIC3 - Prod VLANs

Each  vNIC defined in the service profile can have multiple tagged VLANs  assigned, but just adhere to the requirement that if you have disjoint  L2 networks upstream, all those VLANs must be assigned to the same vNIC.

Have a read through this guide we put together:



CreatePlease to create content