vnic disconnected after user removed it from guest OS

Products

• VMware vSphere ESXi

Issue/Introduction

vnic disconnected without having operations from ESXi or vCenter Server.

Using ESX 7.0 u1, you might see log below. (Log pattern could be slightly different based on ESXi version)

YYYY-MM-DDT09:18:19.283Z| vcpu-1| A000: ConfigDB: Setting Ethernet1.pciSlotNumber = "-1"
YYYY-MM-DDT09:18:19.285Z| vcpu-0| I005: Destroying virtual dev for scsi0:0 vscsi=8198
YYYY-MM-DDT09:18:19.286Z| vcpu-0| I005: VMMon_VSCSIStopVports: No such target on adapter
YYYY-MM-DDT09:18:19.291Z| vcpu-0| I005: Closing all the disks of the VM.
YYYY-MM-DDT09:18:19.291Z| vcpu-0| I005: Closing disk 'scsi0:0'
YYYY-MM-DDT09:18:19.295Z| vcpu-0| I005: DISKLIB-VMFS  : "/vmfs/volumes/#####/#####/#####-000002-delta.vmdk" : closed.
YYYY-MM-DDT09:18:19.297Z| vcpu-0| I005: DISKLIB-VMFS  : "/vmfs/volumes/#####/#####/#####-flat.vmdk" : closed.
YYYY-MM-DDT09:18:19.297Z| vcpu-0| A000: ConfigDB: Setting Ethernet1.present = "FALSE"
YYYY-MM-DDT09:18:19.303Z| vcpu-0| I005: Checkpoint_Unstun: vm stopped for 19819 us
YYYY-MM-DDT09:18:19.303Z| vcpu-0| I005: SCSI: switching scsi0 to push completion mode

Environment

VMware ESXi

Cause

This could happen when guest OS user initiate removing vnic device from guest OS. vnic is treated as a removable device from guest OS and it'll loose connection.

Resolution

If you find Ethernet#.present = "FALSE" in vmx file by vnic removal, power off the VM, set it to True, and then power on the VM again.

Also, disabling hot-remove for the VM could be effective to prevent this behavior.

Disabling the HotAdd/HotPlug capability in virtual machines