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SrikantRajeev

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VMware NSX

Would like to understand how VMware NSX works.
The documents available in internet are not self explanatory.
Its mentioned that VMware NSX provides L2 switching & Routing functionality.
Would like to understand in simple language how it works & what are required for this to make it work.
Avatar of Andrew Hancock (VMware vExpert PRO / EE Fellow/British Beekeeper)
Andrew Hancock (VMware vExpert PRO / EE Fellow/British Beekeeper)
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Have you looked at the documents hosted at VMware here:-

http://www.vmware.com/uk/products/nsx/gettingstarted.html

Including the Getting Started Video

http://featurewalkthrough.vmware.com/#!/nsx

There is an EE Article here as well

https://www.experts-exchange.com/Security/Misc/A_17396-Network-Security-For-NSX.html
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SrikantRajeev

ASKER

How the licensing works for this ?
Any Idea about licensing.
I have few Esxi hosts which we are planning to have NSX on those.
These Esxi hosts are further connected to L2 Nexus 5K which are further connected to the Nexus 7K switches which acts as L3.

All the VLAN's are configured in the Nexus 7K L3 switch & extended into the Esxi host via the L2 Nexus 5K.

With the same setup I am planning to have the NSX on my Exsi hosts.
In this scenario would like to know where will be my L3 will be . Will Nexus 7K will be my L3 in which all the VLANs will be configured
Or should i make my Nexus 5K as my L3.
What is the recommended & the standard practice with respect to NSX
I cannot see any reason why NSX would not replace your existing L2 Nexus 5K, and your L3 Nexus 7K, will continue as is.

BUT, I would check out the documentation, and arrange a trial, to checkout, it's for you!
Thanks.
But would like to clarify again whether the Nexus 5K connecting to the Exsi host should be L2 or L3.
What is the standard design of using NSX.

Is it Exsi with NSX -> L2 5K [Distribution] -> L3 7K [Core]

OR

Is it Exsi with NSX -> L3 5K [Distribution] -> L3 7K [Core]
yeah i have read it.
But i am not able to understand from the document how exactly the inter vlan traffic will work.

For ex there is a VM in VLAN 10 & another VM in VLAN 20.
The L3 information for these VLANs will be defined in the L3 Nexus 7K
So when VM in VLAN 10 wants to communicate with VM in VLAN 20 how NSX does the inter VLAN routing without passing through the L3 Nexus 7K.

If any new VLAN needs to be created for any new VLAN is it required to be configured in Nexus 7K L3 or should it be configured inside the NSX.
This is how we would do it...

Define the VM VLANs in NSX, you want to keep East/West traffic in NSX, and only North/Source traffic to WAN and Internet, via Edge and Transport vLANs.
So u mean to say the VM VLAN needs to be defined in the NSX & not in the L3 Nexus 7K.

If the above is right , for the VLAN's which are already defined in L3 Nexus 7K & for the VMs which have are part of the VLAN how the NSX works in this scenario.
We would define the VLANs in L3 Nexus 7k, if required, otherwise keep all the traffic in NSX between hosts, otherwise traffic will be leaving the host, to go to the Nexus 7K and back!

Once all the VLANs are configured in NSX and Nexus 7k, all will beforwarded to every vSphere host in both clusters.
So for ex for a VM which needs to be part of VLAN 10 will be configured in the NSX.
It will not be configured in the L3 Nexus 7K.

Also as asked before all the EXSI hosts will be connected to Nexus 5K. The Nexus 5K will be L2 switch which will be connected to the Nexus 7K which is the L3 via vPC

My question is should the Nexus 5K be L2 or it should be configured as L3,
So for ex for a VM which needs to be part of VLAN 10 will be configured in the NSX.

Correct.

It will not be configured in the L3 Nexus 7K.

Depends if you need the VLANs in the Nexus 7k. Configure the VLANs in both.

What function does the Nexus 5K perform? Edge ?
Nexus 5K as aggregation switch.
The Nexus 5K will be the switch where all my Esxi hosts will be connected. The Nexus 5K will be further connected to the Nexus 7K L3 switch.
So wanted to know should Nexus 5K be config as L2 switch or L3 switch.
OK thanks.
but in the below blog which you have shared earlier the Nexus FI 62xx is configured as L2.
So in my design instead of Nexus F1 62xx I am using Nexus 5K

How this will be different if I use Nexus 5K instead of Nexus FI 62xx

http://blogs.vmware.com/networkvirtualization/files/2014/02/VMware-NSX-on-Cisco-N7KUCS-Design-Guide.pdf
Where do you want all your routing for intervlans to occur ?

inside NSX, then leave it all in NSX, and use the 5k to do L2.
I want to keep the routing inside the NSX.
So in this case all the L3 IP Address for each VLAN will be configured inside the NSX . Am I right
Yes that's correct, all traffic, and inter vlan routing inside NSX - Correct.
Ok Thanks.
I have 1  final question.
So if i have 5K as L2 switch in between the Nexus 7K L3 & the exsi host which has the NSX how will the routing information is exchanged between the ESXi host & the Nexus 7K L#.
I am attaching the diagram for your reference. Please find it in the attachment.
There are existing VLAN's already configured in the Nexus 7K.
Now i am planning to have NSX on my Esxi host.
From the above discussion I understood that for the VM which will be part of the NSX their corresponding VLAN's will be configured inside the NSX.

Question:
1. With the above scenario my Nexus 5K should it be configured for L2 or L3.
2. If it is L2 how the routing happens between NSX & Nexus 7K core.

Please help me in clarifying this.
All those VLANs will still need to be defined in 5k and 7k, but the routing will be done in NSX.
So what will be the D.G IP Address for the VMs inside the VMware NSX.
Will the VM's D.G will be of the Virtual DLR or will it be the Nexus 7K.

For ex - if the new VM needs to be created for this requirement for ex VLAN 10 , where exactly the VLAN IP will be created.
What will be the D.G of the VM's inside NSX.
ASKER CERTIFIED SOLUTION
Avatar of Andrew Hancock (VMware vExpert PRO / EE Fellow/British Beekeeper)
Andrew Hancock (VMware vExpert PRO / EE Fellow/British Beekeeper)
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Thanks