Configuration of Azure Application GW Load-Balancing

Required

1 virtual networks
1 Scale Set
2 subnets
HTTP server running on both VMs

TCP/IP addressing table

Subnet name	IPv4 range
BLUEVNET Virtual Machines subnet range	172.16.100.0/24
BLUEVNET Application Gateway subnet range	172.16.200.0/24

Node	IPv4 Address
WEB-SERVER 0	LAN 172.16.100.4/24 WAN 52.235.20.35
WEB-SERVER 1	LAN 172.16.100.5/24 WAN 20.220.68.16
APPGW	LAN 172.16.200.10/24 WAN 52.229.110.179

Create the APP. GW. from the portal.azure.com
1. Search for Application Gateways and select Create
2. On the Basics page configure the following info , and hit Next ;
  - Subscription
  - Ressource group
  - Virtual Network
  - Subnet
3. On the Frontend page configure the following info, and hit Next
  - Frontend IP address type
  - Public IP address
  - Select Yes on Use a private IP address
  - Input the application gateway static Virtual Network IP address
4. On the Backend page click Add backend pool and configure the following info and hit Next
  - Name
  - Add VMSS Select your VMSS target
5. Click on the Add routing rule plus sign and configure the following info and hit Next
  - On the Listener page configure the following info
    - Name
    - Listener Name
    - Frontend IP
    - Protocol
    - Port
    - Listener Type
    - Error page url
    - Single Site
    - No URL path-based routing
  - On the Backend targets page configure the following info
    - Backend type pool
    - Backend target click on Add New under Backend Setting
      - Name your backend settings and leave defaults click Add
Review and create

You can now access both web servers from the Application Gateway Public URL. Try turning off one of them and see ! By default it uses round-robin when both are running.