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NotANumber
Contributor
Contributor

How to Add Multiple Port Groups to Single VM Kernel Adapter

I am a total noob when it comes to vmware networking and need assistance please.

I need to configure some new esxi hosts recently added to an existing cluster. I need to add the required ports groups to the single vmkernel adapter in use. Every time I try to add any port group/network it just adds it as new vm adapter and I have tried several different ways following various articles but now I just find myself going down a rabbit hole. All other hosts in the cluster networking goes through the single vm adapter and not sure how this is done.

I have attached an image from a configured host where its networking is only on the single vm adapter, this is what I trying to configure for the new hosts.

NotANumber_0-1610441073065.png

 

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7 Replies
scott28tt
VMware Employee
VMware Employee

@NotANumber 

To be clear, that's not a "single vmkernel adapter" - it's a port group on a vSphere Distributed Switch that is being used by the vmkernel on one existing host (rather than by VMs).

The logic and terminology is the opposite of the way you describe it - vmkernel ports are associated with the port group (in your case dvp_int_mgmt_XXX), either in a 1:1 or Many:1 fashion.

And it sounds like you have new hosts that you would also like their vmkernel ports to be associated with the same port group.

I haven't done this for a long time, but you should be able to do this on those hosts either when creating a new vmkernel port on them or there is an option to migrate your existing vmkernel ports.

 


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Lalegre
Virtuoso
Virtuoso

Hey @NotANumber,

As @scott28tt clearly said previously you are confusing terms. What you are doing that is not working for you is creating new portgroups that if you do not create a VMkernel and associate to it in an ESXi it will be just an empty portgroup.

On your scenario where you are adding new ESXi to the cluster, you need first to add it to the VDS if you did not do it yet, after that you need to do the next:

  1. Select the newly added host on the Host and Cluster view and go to the Networking tab.
  2. Once there select the VMkernel Adapter option -> Add new Networking. Inside there you need to click on VMkernel Network Adapter.
  3. On the next screen you need to select the Existing network option where you can select the Distributed Portgroup that you are currently using for your existing ESXis.

Next steps are to fill the IP information, security, netmask, etc. What you will have as a result is a new VMkernel assigned to a Portgroup on one host. If you want to do it in more than one then you will need to follow the same 3 steps but clicking on another host.

Hope I explained it good to you. If you still have doubts follow the next procedure with images, it is slightly different as it is using vSphere Web Client and not the HTML5 one: https://subscription.packtpub.com/book/virtualization_and_cloud/9781849684026/8/ch08lvl1sec92/creati...

Let us know how it goes!

 

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NotANumber
Contributor
Contributor

Thanks for the help, I'm starting to understand it better now. The hosts are added to DvSwitch fine using the management port group but when I add new networking it adds it fine but is using new vmkernel and another IP address which we are short on. Same if try migrating, I am using another new IP. Does this make sense or am still being a noob, sorry in advanced. I have always done it as new adapter in the past so never been an issue.

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Lalegre
Virtuoso
Virtuoso

Oh okay I am seeing now what is you want to achieve and let me tell you that is not possible. You cannot share the same IP with two VMkernels as they are uniquely per host.

This has a really easy explanation, each host initiates the connection for Management, vMotion, vSAN, etc with their unique IP, in case they have a duplicated IP with another host you will have a conflict, same as what would happen with a Windows with duplicated IP.

So I recommend you think about migrating to a new VLAN with a bigger network range.

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NotANumber
Contributor
Contributor

Thanks, the issue is the current hosts in the cluster port groups are all using a single vm adapter and a single IP. See below, sorry again if I got this wrong. The new host can only have a single vm adapter with the all port groups using that vm adapter.

NotANumber_1-1610534982775.png

 

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Lalegre
Virtuoso
Virtuoso

Hey @NotANumber,

You are getting confused again, please see the next quick graphic for better understanding:

Lalegre_0-1610539127674.png

Sorry for not being so detailed, I did it really quick. What I am trying to show you there is a simple construction of a cluster that share the same portgroups not only for VMKernel but also to connect virtual machine as in essence is just a Distributed Portgroup not a "vm adapter or vmkernel adapter". On both of them you can connect a VM or a VMKernel as you need to.

A VMkernel or a vNIC (VM Adapter) is always connected to ONE portgroup, the difference between them is that the VMKernel is used for VMware traffic such as vMotion, MGMT, vSAN, etc and the vNIC is used to the Virtual Machines that you are deploying on top of your hosts.

So going back to the problem you have there is no possibility that your current hosts are all using the same VMKernel as there is one per host and they cannot have the same IP as you would have conflict and disconnections everywhere. But yes, they share the Distributed Portgroup that have the VLAN281 for MGMT (as I can see in the picture). Why is that? Becuase as the name says this is a group of ports which means multiple VMKernels or VMs can be connected to the same one without any issues.

To finalize, what you need to do for any new host is to create a new VMkernel on the portgroup that you are using for MGMT on the other hosts with a unique IP per host.

Hope I was clear with the explanation however if you still have doubts I can go more in deep.

 

NotANumber
Contributor
Contributor

Thanks Again. I'll speak to our network team and get them to sort me some additional IP's.