Network connectivity lost on ESXi after host upgrade or reinstall

Products

• VMware vSphere ESXi

Issue/Introduction

• ESXi has been upgraded from major rev to major rev (Ex. 7.x to 8.x) OR ESXi has been reinstalled on the host
• No other updates have occurred
• The ESXi host is a standalone server, not part of a converged system such as UCS.

Cause

vmnic alias to PCI location has changed after the upgrade, causing the vSwitch to uplink mappings to no longer reflect the correct network layout.

Resolution

Poweroff the ESXi host, wait for 15-30 seconds, and then power the host on. 

If the issue persists vmnic aliasing can be updated following:  How VMware ESXi determines the order in which names are assigned to devices