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Mixed "Direct Attach" and "Fabric Attach" SAN on VC FlexFabric ports

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Mixed "Direct Attach" and "Fabric Attach" SAN on VC FlexFabric ports

Stojce had a SAN attach question for VC FlexFabric:




Dear team,


Is it possible single blade in the enclosure to connect both to Direct Attached 3PAR and also to other storage that is Fabric Attached (through FC switch) , using FlexFabric Interconnects?




Input from Chris:

The last I read it is supported, different SANs defined for each. Say X1 & 2 on both VCs would be SAN one and two direct attach, X3 & 4 on VC1 & 2, San A & B, Fabric attach. Two dual ports FCoE HBA on each profile for full height blades. I don’t know if it would be good to cross the HBA connection or keep them one HBA for direct and the other for Fabric. A single HBA connected to one Direct and one fabric would not provide high availability, especially during a FW upgrade.


I think it is one of the cookbooks where I saw this.


From Dave:

Direct Attached is only supported to be connected to a 3PAR storage device DIRECT CONNECTED( No SAN Switch).

Fabric Attached is connecting through a SAN switch before connecting to a storage device.


That being said no, both uplinks cannot be used for both in one connection.


They could be shared, one to Direct and the other to Fabric.


Reply from Alex:

Yes, this would work. If you have a pair of FlexFabric adapters, first two FCoE connection can go to a DirectAttach SAN, second pair can go to any other FabricAttach SAN. You can’t have one connection mapping to two different SANs.


And input from Dan:

I can definitely confirm this works.


I setup a PoC environment recently where X1 and X2 were Direct Attached to a v400, X3 went to the Customer’s existing Brocade SAN and X4 went to a pair of Brocade’s we dropped in when we decided to turn it into a Matrix PoC (we didn’t want SPM and BNA controlling their existing switches so we brought in our own to show the automation)


So 3 different pairs of Fabrics and using both Fabric and Direct attached on FlexFabric modules.

Everything went very smooth.


The only thing to watch for is right now you have to select at least 1 uplink port in order to then change the mode to Direct Attached.  Your eyes want to work top down when creating SAN Fabrics in VC and here you go kind of backwards (bottom up).

This caused us to do Fabric B wrong (Fabric attached) and then have to re-do it 3 minutes later when we noticed.

Not a huge deal, just something to be aware of.






Other comments or questions?