One big flat Virtual switch vs multiple Virtual switches

[sansaran]

experts,

   what is the advantage of having one big flat Virtual switch Vs multiple Virtual switches for all type of virtual machine traffic ( Management, Vmotion,Vm Network). Any improvement in performance.

what is the advantage of having Management network and Vm network on two different Vlans.  improvement in performace or security ?

Our current configuration has one virtual switch with all of eight Physical nics are assigned to it.

  Vswitch 0 <--- vmnic0,1,2,3,4,5,6,7

      |

        Management network (Vlan 100) <---- Vmnic0 ( active),Vmnic7 (standby)

        |

        Vmotion      (Vlan 150)               <----- Vmnic7 (active),Vmnic 0 (standby)

        |

        Vm Network    (vlan 100)           <------ Vmnic1,2,3,4,5,6 ( all active)

We will be setting up new Vmware environment( 5.0) and i would like to configure two Virtual switchs as follows

  Vswitch 0 <--- Assigning two physical Nics ( Vmnic 0, Vmnic 7)     

       |

        Management Network ( Vlan 100) <----- Vmnic0(active), Vmnic7(standby)

        |

        Vmotion                     (Vlan 150) <------ Vmnic7(active), Vmnic0(standby)

And Allowing  only Vlan traffic 100 and 150 to Vmnic0 and Vmnic7

Vswitch 1 <---- Assigning remaining Physical Nics ( Vmnic1,2,3,4,5,6)

     |

    VM Network    (vlan 101)      <-------- Vmnic1,2,3,4,5,6  ( All active)

Allow only Vlan traffic 101 onto above Nics

I am thinking of proposing above configuration.  if i go with above setup, will i get any performace improvement? or any other advantages. Please explain?

[Sreejesh_D]

its an ideal configuration. VLAN will help in reducing broadcast traffic as each broadcast will be sent on to the relevant VLAN only. Also VLAN will enhance the security since Virtual Machine traffic is seperated from the critical VMkernel network (Host management and vmotion).

[rickardnobel]

sansaran wrote:

I am thinking of proposing above configuration.  if i go with above setup, will i get any performace improvement? or any other advantages.

I do not think there should be any performance differences in the two setup options you have. The only advantage of creating two vSwitches would be to simplify configuration, less risk for errors if configuration lots of hosts and easier to quickly verify that the config is correct.

A small advantage with creating one large vSwitch is that you could (if you wish) experiment with using multi-NIC-vmotion in ESXi, and assign more VMNICs for vMotion and it would be easy to give the VMNIC "back" to the VMs later if wanted.