DVS Status Shows as "Down" When we select Adding/Managing Hosts on Distributed Virtual Switch (DVS)

Products

• VMware vCenter Server
• VMware vSphere ESXi
• VMware NSX

Issue/Introduction

• You may observe the Distributed Virtual Switch (DVS) status showing as "Down" when attempting to add or manage an ESXi host on the DVS. This issue can prevent proper network configuration and host connectivity through the DVS.

 

Unable to vMotion the VM's.

Below is the error message during VM migration  

• "Currently connected network interface" 'Network adapter #' uses network 'DVSwitch[<UUID>] NSX port group [<name>]', which is not accessible.

Environment

VMWare NSX
VMware vSphere ESXi 7.x
VMware vCenter Server 7.0.x
VMware vSphere ESXi 8.x
VMware vCenter Server 8.0.x
VMware vSphere ESXi 9.x
VMware vCenter Server 9.0.x

Cause

This issue occurs when the NSX agent (nsxa) goes down on the ESXi host.

A review of the nsxsyslog indicates disconnection-related events, showing that the NSX Manager became temporarily unreachable. In such scenarios, vCenter loses connectivity with the NSX Manager, which can lead to the Compute Manager appearing as "Disconnected" from NSX.

When this condition occurs, NSX-prepared ESXi hosts will report the VDS status as "Down" and experience related issues, such as vMotion failures. This is typically caused by a network reachability issue affecting the NSX Manager VM (for example, gateway connectivity loss), contributing to a temporary loss of communication. Once network connectivity is restored and the NSX Manager is reachable from vCenter again, normal system behavior resumes.

Resolution

To resolve and troubleshoot this issue, perform the following checks:

1. Verify NSX Manager VM Connectivity: Ensure that the NSX Manager VM is powered on and accessible over the network. Check for any underlying physical network or routing issues that might be blocking traffic to and from the NSX Manager.

2. Check the NSX Manager Gateway: Verify the default gateway configuration for the NSX Manager VM and ensure the gateway is reachable.

3. Verify Compute Manager Status: Log in to the NSX Manager UI and check the status of the Compute Manager (vCenter Server). Ensure its registration status is "Up" and connected successfully.

References

For more detailed information, please refer to the following Broadcom Knowledge Base articles:

• VDS status is Down on multiple ESXis

• DVS status shows as Down when we select adding/managing hosts