Managed offerings in the public cloud are an alternative to operating a load balancer locally. These already cover many typical requirements in terms of high availability, scalability and security. Although such services often do not offer the full range of functions such as F5 Big-IP or Citrix Netscaler, they are impressively easy to set up and operate. In the Azure cloud, Microsoft offers the Azure Application Gateway as a layer 7 load balancer.
Load balancers are a central component for the operation of web applications – both for VM and container-based applications. However, their classic design presents IT managers with a number of challenges, particularly in terms of operation and the required expertise. If the application is to meet requirements in terms of high availability and scalability, for example, a number of prerequisites must be met: Depending on the criticality, several data centers as well as management and monitoring tools are required.
A layer 7 load balancer that works at HTTP level is typically used for hosting web applications. However, this technology is also subject to the challenges described above. In Azure, however, Microsoft wants to simplify this with the Azure Application Gateway (AAG) – more on this in a moment. To avoid confusion, here are all the load balancers in Azure:
– Azure Loadbalancer: a layer-4 service that works on a TCP/UDP basis.
