backplane network in AOS 5.5


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Hi

A change in AOS 5.5 is backplane network. after added the backplane network which will load the storage traffic and the original network (eth0) will become to management network.
I installed AOS 5.5 in my lab and find that the CVM have a strange change for the backplane nic(eth2) in the port group as the following pictures,but the network is normal and all the backplane NICs in CVMs are connected.

Is it by design or I have missed something?





7 replies

Userlevel 4
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chenzh4

We have a new feature "NETWORK SEGMENTATION " introduced in AOS 5.5, and this new "eth2/backplane" adapter is created for this feature.

Please refer below document for more info.

https://portal.nutanix.com/#/page/docs/details?targetId=Web-Console-Guide-Prism-v55:wc-network-segmentation-wc-c.html
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Yes, I enabled the network segment according to the manual you provided.

What I want to know or my question is why the PORG GROUP of eth2 for CVM become EMPTY after enabled the network segments as the picture I attached?
When porggroup become empty but the network is connected in the vlan,it is very strange.
Is it by design or I missed somthing?

Thanks.
Userlevel 4
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chenzh4

Haven't seen that before. Can you verify this in webclient?
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In web client.
there is no information in host network configuration, but in VM hardware configuration, the eth2 belong to backplane portgroup. but in powercli, we cannot see the vm in the backplane portgroup. SO strange!


Userlevel 2
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chenzh4 I was able to replicate this issue in the lab. If you check the pictures closely before network segmentation was enabled you see "Backplane Network" as a VirtualMachine Port group. After you have enabled network segmentation you see the "Backplane Network" as VMKernel port group. We cannot connect a vmkernel port to a VirtualMachine port group so what has happened when you enabled network segmentation is, the "Backplane Network" of type Virtual Machine port group was deleted by the CVM and a new port group was created with the same name "Backplane Network" of type as VMKernel port group. But the CVM's vmx file was not updated with the correct portgroup.


I re-created this issue on AOS 5.1.2 cluster by following the steps below,

1.Create a virtual machine port group with name "Backplane Network"
2.Add a new network adapter to the CVM and connect the network adapter to "Backplane Network" port group and power on the CVM.
3. After CVM is powered on, Click Edit settings and uncheck "Connected" box for the newly added network adapter
4. From the GUI deleted the "Backplane Network" port group
5. Now create a new port group of type "VMKernel" and name it as "Backplane Network" and give it an ip address
6. Now got to CVM and click Edit Settings and check the newly added network adapter it should show empty since there is no more a virtual machine network called "Backplane Network"

I will test it on AOS 5.5 cluster and update this thread.
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Chandruyes, you are right. The port group is changed from vm port group to vkernel portgroup(the port group name is same). so the CVM cannot placed eth2 on it. but the network is connected between CVMs in the backplane subnet eventhough there is no portgroup belong to them.It is interesting.
Userlevel 2
Badge +12
@chenzh4 Found the issue, when we upgrade the AOS from any version to 5.5 a new Virtual Machine port group named "Backplane Network" is created and the CVM is given a new nic (eth2) in this port group, even though you haven't enabled network segmentation. When you enable Network segmentation, the code goes and removes the Virtual Machine port group "Backplane Network" and creates a new VMKernel port group with the same name "Backplane Network". Since the virtual machine port group was deleted your CVM shows empty in the network box for the new nic if you run esxcfg-vswitch -l you will see the "Backplane Network" has 2 connected ports one is the vmkernel and other is the CVM's eth2 though it is not reflected in the GUI. I have logged an engineering ticket but after bit of testing the functionality still remains except it confuses the admins.

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