Access Layer Migration Solutions

The access layer is composed of Nginx/OpenResty, hardware or software load balancer, microservice gateway Kong/Zuul, and DNS, providing an entry for external access to an application. Generally, the components are migrated by reconfiguration.

**Table 1** Access layer migration methods
Technical Component	Function	Migration Method
Nginx/OpenResty	Forwards traffic.	Solution 1: Use SMS to migrate the server where the Nginx or OpenResty service is running to Huawei Cloud and modify the corresponding forwarding policies. Solution 2: Redeploy Nginx or OpenResty on a Huawei Cloud ECS, copy the configuration file from the source server to the destination server, and modify the forwarding policies in the configuration file.
Load balancer	Forwards Layer 4 or Layer 7 requests.	Copy the load balancing policies from the source to Huawei Cloud ELB.
Kong/Zuul gateway	Microservice gateway	Solution 1: Use SMS to migrate the server where the Kong/Zuul gateway service is running to Huawei Cloud. Solution 2: Redeploy the Kong/Zuul gateway on a Huawei Cloud ECS, copy the source configuration file to the ECS, and modify the forwarding policies.
DNS	Resolves the internal and external domain names of an application to IP addresses.	Solution 1: Replace the DNS used on the source server with Huawei Cloud DNS and reconfigure the mapped IP addresses. Solution 2: Deploy DNS on a Huawei Cloud ECS and reconfigure the mapped IP addresses. Solution 3: Use SMS to migrate the source DNS server to Huawei Cloud and modify the DNS configurations.