Are vlan's needed

[Bobby P]

We have a single UCS-Mini-5108 with 3 B-200 blades.  We will be running vMware 6.5 on the blades.  We've setup a few vlans in UCS Manager but do we need them.  I'd rather setup vNics ( around 30 to 39) and equally assign the vNics to each Blade and in vMware create virtual switches with vlan assignments

We have vlan's configured on the switches that the ethernet uplinks on the FI's are connected to.  It seem unnecessary to have on the UCS.

[mojafri]

Hi Bobby,

Could you please elaborate more? So are you planing to just run everything on a default vlan i.e. vlan-1 which you can't delete? 

If you say your uplinks have vlans, then you definitely need vlans on UCS as well, else how you gonna trunk them? Just having vlans on vswitch won't help as you have to tag those on vnic level as well, and for that you need vlan on UCS.

Regards,

MJ 

[Bobby P]

We have on both FI's Eth 1/1 and 1/2 connected to 10Gig ports on Catalyst 9300 switches.  The ports are set as trunk ports.  On the Catalyst we have 4 vlans and SVI's for those vlans.  We will need to tag traffic from virtual switches created in vmware but don't see a need for any vlan other than the default vlan in UCS manager.

If we created vlans in UCS Manager how is that information presented to vmware?  One of our tech's has configured vlans in the UCS manager but when installing vmware all we see are the nics.  There is no information indicating what vlan that nic is associated with.

I'd rather create vnics, assign those nics to each blade, and let the vswitches do the vlan tagging once their setup.

[mojafri]

If you are not providing vlans in vnic on UCS == not allowing vlans on a trunk link. Your vmware will see vnics with the mac addr you assigned from UCS as well as “observed IP ranges” and “observed VLANs’” based on observed traffic, i.e. no probing.

Connectivity overview:  esix(vmnic)<--trunk-link--->vnic(ucs)--FIs(ucs)<--trunk-link--->Uplink switch

Example

 

Please rate if you find it helpful.

Regards,

MJ

[Bobby P]

When you say observed IP ranges that then it would be all the IP / vlans on the switches that are passed down to the UCS and presented to the vmware servers. 

If vlan were used on the vnic what would that mean in vmware.  Would that mean traffic for the VM would be tagged?   If as an example we had a vlan id 10 setup in UCS.  In that vlan each server had 3 vnics.  In Vmware there will be VM's that need that vlan ID .  If a vswitch is created using the vnics that have a vlan id well the vm's using that vswitch have their traffic tagged with the vlan id?