<p>This article describes the components and instance deployment structure of Ping An Cloud ELB.</p> <p><span style="font-size:18px"><strong>Components</strong></span></p> <p>ELB service includes the following three parts:</p> <p>&bull;&nbsp;<strong>ELB Instances</strong></p> <p>ELB instances in running status can provide ELB services. An ELB instance provides the s service IP address as a unified interface for clients to access. You can configure each ELB instance with multiple listeners to provide multi-port listening services for the same service IP address. You can configure each listener with a specific server resource pool, or specify multiple listeners to the same server resource pool. Create an ELB instance first and add a minimum of one listener and one back-end service resource if you need to use ELB service.</p> <p>&bull;&nbsp;<strong>Listener</strong></p> <p>Listener is used to receive the clients requests and forward them to the host in the server resource pool, and perform a health check on the back-end host.</p> <p>&bull;&nbsp;<strong>Server resource pool</strong></p> <p>Server resource pool consists of a set of ECS instances or BMS instances to receive front-end requests. You can add one or more ECS instances or BMS instances to the server resource pool and configure weights and back-end service ports.</p> <p><strong>External ELB instance deployment structure</strong></p> <p><img src="https://obs-cn-shanghai.yun.pingan.com/pcp-portal/20201307183220-1b4d431a9c58.png" style="height:361px; width:784px" /></p> <p><strong>Internal ELB instance deployment structure</strong></p> <p><img src="https://obs-cn-shanghai.yun.pingan.com/pcp-portal/20201307183349-1ec346509778.png" style="height:346px; width:830px" /></p> <p><strong>Classic ELB instance deployment structure</strong></p> <p><img src="https://obs-cn-shanghai.yun.pingan.com/pcp-portal/20201307183431-158bedac9089.png" style="height:338px; width:830px" /></p>