VMs lose connectivity on a NSX prepared host

Products

• VMware NSX

Issue/Introduction

VMs connected to a NSX managed network whether it is overlay or VLAN-back segment lose connectivity after performing DVS upgrade. 

The problem host showing up healthy from NSX UI under "System", "Fabric", "Hosts" even during the outages. 

In vCenter logs, you may find:

hostd:

2026-01-23T11:44:42.907Z In(166) Hostd[<hostd-process-id>]: [Originator@6876 sub=Vimsvc.ha-eventmgr opID=<opID> sid=<sid> user=vpxuser:<no user>] Event 256221 : Reconfigured ports in the vSphere Distributed Switch  in <datacenter-name>.
2026-01-23T12:00:45.274Z Er(163) Hostd[<hostd-process-id>]: [Originator@6876 sub=Hostsvc.NetworkProvider] Component [com.vmware.common.opaqueDvs.status.component.vswitch] status [down] on DVS
2026-01-23T12:00:45.274Z In(166) Hostd[<hostd-process-id>]: [Originator@6876 sub=Hostsvc.NetworkProvider] Setting NSXT status on DVS [<DVS-ID>] to [down]
2026-01-23T12:00:45.336Z In(166) Hostd[<hostd-process-id>]: [Originator@6876 sub=Vimsvc.ha-eventmgr opID=<opID> user=vpxuser:<no user>] Event 256240 : Reconfigured ports in the vSphere Distributed Switch  in <datacenter-name>.

Running below command you will see similar output for opaqueDVS status and vswitch.disabled flag:

• net-dvs -l | grep -E "com.vmware.common.alias|com.vmware.common.opaqueDvs.status.component.vswitch|com.vmware.vswitch.disabled"
  • com.vmware.common.alias = <DVS name> ,        propType = CONFIG
  • com.vmware.common.opaqueDvs.status.component.vswitch = down ,    propType = CONFIG
  • com.vmware.vswitch.disabled = true ,    propType = CONFIG

Below command will confirm the existence of incorrectly set parameters in the DVS:

• net-dvs -l | grep -E "nsx.kcp.enable|nsx.spf.enabled|nsx.vdl2.enabled|nsx.vdsSecurity.enabled"
• The output contains any of the following:
  • com.vmware.nsx.kcp.enable = true ,      propType = CONFIG
  • com.vmware.nsx.spf.enabled = true ,      propType = CONFIG
  • com.vmware.nsx.vdl2.enabled = true ,      propType = CONFIG
  • com.vmware.nsx.vdsSecurity.enabled = true ,      propType = CONFIG

 

Environment

VMware NSX

Cause

DVS upgrade triggers a brief DVS reboot, however, some NSX parameters that were incorrectly retrieved from vCenter prevents the DVS from starting up. 

Resolution

Workaround:

Execute the below commands to restore connectivity (order of command execution matters):

• net-dvs -s com.vmware.common.opaqueDvs.status.component.vswitch=up -p hostPropList <dvsName>
• net-dvs -u com.vmware.nsx.kcp.enable -p hostPropList <dvsName>
• net-dvs -u com.vmware.nsx.spf.enabled -p hostPropList <dvsName>
• net-dvs -u com.vmware.nsx.vdl2.enabled -p hostPropList <dvsName>
• net-dvs -u com.vmware.vswitch.disabled -p hostPropList <dvsName>
• net-dvs -u com.vmware.host.feature.container -p hostPropList <dvsName>
• net-dvs -u com.vmware.nsx.ens.loadbal -p hostPropList <dvsName>
• net-dvs -u com.vmware.nsx.ens.overlayl2flow -p hostPropList <dvsName>
• net-dvs -u com.vmware.nsx.vdsSecurity.enabled -p hostPropList <dvsName>
• net-dvs -s com.vmware.vswitch.disabled=false -p hostPropList <dvsName>

Running the above commands alone will not prevent this issue from recurring. Please open a Broadcom Support Request and reference this KB. 

Additional Information

If you are contacting Broadcom support about this issue, please provide the following:

• NSX Manager log bundles
• Impacted ESXi host logs
• Text of any error messages seen in NSX GUI or command lines pertinent to the investigation
• Handling Log Bundles for offline review with Broadcom support

Collect Support Bundles for Troubleshooting NSX-T
Uploading files to cases on the Broadcom Support Portal
Creating and managing Broadcom support cases