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Usage Restrictions and Precautions
1. Load balancing does not support cross-region deployment , that is to say, the back-end ECS of a load balancing instance must be an ECS instance belonging to the same region.
2. In the Layer 4 (TCP protocol) service, the ECS added to the backend cloud server pool is not currently supported as both a Real Server and a client to send requests to the load balancing instance where it is located. Because the returned data packets are only forwarded inside the cloud server without load balancing, it is impossible to access the VIP through the ECS configured in the load balancing.
3. Before providing external services through load balancing, first ensure that all application services on the load balancing backend ECS have been completed and correctly configured, and that the service can be accessed correctly through the service address of the ECS.
4. Load balancing does not provide data synchronization services between ECSs. If the application service deployed on the load balancing backend ECS is stateless, data can be stored through an independent ECS or RDS service; if it is deployed on the load balancing backend The application services on ECS are stateful, so it is necessary to ensure that the data on these ECSs is synchronized .
5. When the service address (IP) of the load balancing instance has been resolved to a normal domain name for external services, please do not delete the load balancing instance at will. Deleting a load balancing instance will release the service address (IP) of the load balancing instance together, resulting in interruption of services already provided to the outside world. If you create a new load balancing instance, the system will reassign a service address (IP).
6. The load balancing does not limit the public IP of the load balancing through ECS ping. However, for some of the newly purchased ECS nodes in Qingdao, Beijing and Hangzhou, the private network IPs that cannot be pinged through ECS for load balancing. This limitation does not affect the communication between the load balancer and ECS.