Creating an NSX logical switch fails with the error: Unable to allocate an available resource

Products

• VMware NSX

Issue/Introduction

• Cannot create an NSX logical switch.
• Creating an NSX logical switch fails.
• You see the error:
  
  Unable to allocate an available resource
  
  
• You have installed the network virtualization components and configured VXLAN on the appropriate clusters.

Environment

VMware NSX for vSphere 6.x

Cause

This issue occurs if Segment ID Pool and Multicast Address Range are not assigned to the NSX Manager.

Resolution

To resolve this issue, you must specify a segment ID pool for each NSX Manager to isolate your network traffic. If an NSX controller is not deployed in your environment, you must add a multicast address range to help in spreading traffic across your network and avoid overloading a single multicast address.

 

To provide Segment ID range and to enable multicast addressing:

1. Log in to the vSphere Web Client.
2. Click on Networking & Security and click Installation.
3. Click the Logical Network Preparation tab and click Segment ID.
4. Click the Edit icon.
5. Type a range for segment IDs. For example, 5000-5200.
   
   The segment ID range determines the maximum number of logical switches that can be created in your infrastructure.
   
   
6. If you do not have a deployed NSX controller in your environment. Select the enable multicast addressing option and enter an address range. For example, 239.1.1.10-239.1.1.20

For more information, see the NSX for vSphere Installation and Upgrade Guide.