Management connectivity is lost when bringing a new system online

Products

• VMware vCenter Server

Issue/Introduction

• When configuring new hosts to add to this cluster, mgmt. connectivity is lost when the host is added to the DVS.
• The current mgmt. portgroup is configured to use a LAG. 
• There is an extra NIC available for use on the ESX host.

 

Cause

• When adding the host to VC, the LAG is not yet created on the host, therefore when the host is added to mgmt. portgroup on DVS, the host becomes unreachable. 
• When host is added to mgmt. portgroup which ONLY uses a LAG, communication is lost as there is no LAG interface configured. 

Resolution

• Do not add the new ESX host to DVS when adding the host to vCenter for the first time.
• Add new ESX host to vCenter but do not modify networking.
• Once the host is in VC inventory, configure the LAG. 
  • Please reference the following KB for steps configuring the LAG and adding the host to the VDS: Configuring a LAG on a vSphere Distributed Switch Port Group when using LACP