Elastic Load Balance User Guide Date 2020-07-30 Elastic Load Balance User Guide Contents Contents 1 Service Overview..................................................................................................................... 1 1.1 What Is Elastic Load Balance?............................................................................................................................................ 1 1.2 Product Advantages................................................................................................................................................................2 1.3 Application Scenarios............................................................................................................................................................. 3 1.4 How ELB Works....................................................................................................................................................................... 5 1.5 Network Type........................................................................................................................................................................... 6 1.6 ELB and Other Services......................................................................................................................................................... 8 1.7 Product Concepts.....................................................................................................................................................................8 1.7.1 Basic Concepts...................................................................................................................................................................... 8 1.7.2 Region and AZ.................................................................................................................................................................... 10 2 Load Balancer.........................................................................................................................12 2.1 Network Type......................................................................................................................................................................... 12 2.2 Preparing for Creation.........................................................................................................................................................13 2.3 Creating a Load Balancer................................................................................................................................................... 15 2.4 Changing Load Balancer Settings................................................................................................................................... 17 2.5 Binding or Unbinding an EIP.............................................................................................................................................18 2.6 Deleting a Load Balancer................................................................................................................................................... 18 3 Listener.................................................................................................................................... 20 3.1 Overview.................................................................................................................................................................................. 20 3.2 Protocols and Ports.............................................................................................................................................................. 21 3.3 Adding a Listener.................................................................................................................................................................. 22 3.4 Load Balancing Algorithms............................................................................................................................................... 27 3.5 Sticky Session......................................................................................................................................................................... 28 3.6 Access Control........................................................................................................................................................................ 29 3.7 Modifying or Deleting a Listener.................................................................................................................................... 31 3.8 Advanced Settings for HTTP or HTTPS Listeners....................................................................................................... 31 3.8.1 Forwarding Policy.............................................................................................................................................................. 31 3.8.2 Mutual Authentication.................................................................................................................................................... 35 3.8.3 HTTP/2.................................................................................................................................................................................. 40 3.8.4 HTTP Redirection to HTTPS........................................................................................................................................... 41 3.8.5 SNI.......................................................................................................................................................................................... 43 4 Backend Server.......................................................................................................................44 2020-07-30 ii Elastic Load Balance User Guide Contents 4.1 Overview.................................................................................................................................................................................. 44 4.2 Configuring Security Group Rules................................................................................................................................... 45 4.3 Adding Backend Servers to or Removing Backend Servers.................................................................................... 47 5 Health Check.......................................................................................................................... 53 5.1 Configuring a Health Check.............................................................................................................................................. 53 5.2 Disabling the Health Check Function............................................................................................................................ 55 6 Certificate................................................................................................................................56 6.1 Certificate and Private Key Format.................................................................................................................................56 6.2 Converting Certificate Formats........................................................................................................................................ 57 6.3 Creating a Certificate...........................................................................................................................................................58 7 Access Logging....................................................................................................................... 61 8 Monitoring.............................................................................................................................. 66 8.1 Monitoring Metrics............................................................................................................................................................... 66 8.2 Setting an Alarm Rule......................................................................................................................................................... 71 8.2.1 Adding an Alarm Rule......................................................................................................................................................71 8.2.2 Modifying an Alarm Rule............................................................................................................................................... 71 8.3 Viewing Metrics..................................................................................................................................................................... 72 9 Auditing................................................................................................................................... 73 9.1 Key Operations Recorded by CTS.................................................................................................................................... 73 9.2 Viewing Traces....................................................................................................................................................................... 74 10 FAQs....................................................................................................................................... 76 10.1 Questions Summary.......................................................................................................................................................... 76 10.2 ELB Usage............................................................................................................................................................................