Azure 2 load balancers in Active/Passive mode

Question

On Azure how can I have 2 load balancers in Active/Passive mode, so that if one goes down the other one can become active?

Answer 1

If you have two public-facing load balancers, you could use Traffic Manager to do failover with two endpoints. That is to add your load balancer public frontend IP address as the endpoint and configure the routing method (based on geographic location, priority, weighted, performance, multivalue, subnet) using Traffic Manager. Then if one endpoint goes down, Traffic Manager will direct the traffic to another endpoint.

Traffic Manager works at the DNS level, consider the DNS resolution might fail sometimes. You could read recommendations for Traffic Manager.

Traffic Manager is a possible failure point. Review the Traffic Manager SLA, and determine whether using Traffic Manager alone meets your business requirements for high availability. If not, consider adding another traffic management solution as a failback. If the Azure Traffic Manager service fails, change your CNAME records in DNS to point to the other traffic management service.

For more references, you could read this SO thread.