In an environment with multiple availability zones, the NSX Advanced Load Balancer Controller nodes run in the first availability zone. If a failure occurs in the first availability zone, the NSX Advanced Load Balancer Controller nodes are failed over to the second availability zone.

NSX Advanced Load Balancer Controller

NSX Advanced Load Balancer Controller cluster requires two out of three nodes to be up, for the control plane to continue regular function. It is recommended that all three nodes of the NSX Advanced Load Balancer Controller cluster are deployed on ESXi hosts residing in the first availability zone.

Note:

  • vSphere HA will recover the NSX Advanced Load Balancer control plane upon a fault domain failure event.

  • vSphere DRS will re-balance the NSX Advanced Load Balancer Controller placement onto the ESXi hosts in the first availability zone.

  • NSX Advanced Load Balancer Controller deployment should follow the requirements of a single availability zone design.

Table 1. Design Decisions on Deployment of NSX Advanced Load Balancer Controllers in Multiple Availability Zones

Decision ID

Design Decision

Design Justification

Design Implication

AVI-VI-VC-001

When using two availability zones, add the NSX Advanced Load Balancer Controller cluster nodes to the first availability zone VM group.

Ensures that, by default, the NSX Advanced Load Balancer Controller cluster nodes are powered on in the primary availability zone hosts group.

After the implementation of the second availability zone for the management domain, you must update the VM group for the primary availability zone virtual machines to include the NSX Advanced Load Balancer Controller cluster nodes.

NSX Advanced Load Balancer Service Engine

Applications requiring load balancing, might intend to use High-Availability between the two stretched locations. In such a situation care must be taken to place NSX Advanced Load Balancer SEs between the two physical locations and to carefully place load-balanced applications on these NSX Advanced Load Balancer SEs.

Table 2. Design Decisions for placing applications on NSX Advanced Load Balancer Service Engines in a Multi Availability Zone environment

Decision ID

Design Decision

Design Justification

Design Implication

AVI-VI-VC-002

Create a VM groups for the NSX Advanced Load Balancer SE VMs.

Ensures that the NSX Advanced Load Balancer SE VMs can be managed as a group and added to VM/ Host rules.

User must add each NSX Advanced Load Balancer SE VM to the primary availability zone.

AVI-VI-VC-003

Create a should-run VM-Host affinity rule to run all NSX Advanced Load Balancer SEs on the group of hosts in the first availability zone.

Ensures that all NSX Advanced Load Balancer SE VMs are in the first availability zone.

During normal operation, there would not be any NSX Advanced Load Balancer SEs running in the second availability zone. Therefore all apps would be active in the first availability zone.