You can interact with the internet using common public IP addresses, elastic public IP addresses, NAT gateways, and load balancers.
Normal Public IP
When creating a cloud server instance, you can choose to allocate a common public IP address to the instance. The system will assign an IP address to your cloud server, allowing it to access and be accessed from the internet.
Common public IPs cannot be dynamically bound or unbound with resources like CVMs. However, you can convert a common public IP to an elastic public IP.
Elastic Public IP (EIP)
An EIP is an independently owned IP resource. Unlike common public IPs, which are tied to cloud servers and follow their lifecycle, elastic public IPs can be decoupled from cloud servers and operated on as standalone cloud resources.
For operations such as application, binding, and release of elastic public IPs, see EIP - Operation Steps.
EIP has the following advantages:
- Independently Held Resources
EIPs can be independent resources in your account, eliminating the need to purchase them in conjunction with cloud servers. They can be operated on as standalone cloud resources. - Elastic Binding and Unbinding of Resources
Elastic public IPs can be dynamically bound and unbound with cloud servers and other resources, offering flexibility and high availability.
NAT Gateway
If you have multiple cloud servers that need to access the internet through a single public IP, NAT gateway can meet your requirements. NAT Gateway provides SNAT and DNAT functions for cloud servers within private networks, facilitating the setup of public network egress and service provision.
For configuration operations related to NAT gateway, please refer to NAT Gateway.
NAT Gateway has the following advantages:
- Secure Public Network Access
NAT Gateway provides SNAT and DNAT functions, allowing communication with the internet while hiding the IP addresses of hosts within the VPC, thus ensuring security. - High Availability
NAT Gateway features dual-machine hot standby and automatic hot switch, supporting up to 5Gbps forwarding capacity, providing robust support for large-scale public network applications. - Flexible Configuration
You can modify the specifications of the NAT Gateway according to your needs, allowing for flexible configuration.
Cloud Load Balancer (CLB)
Cloud Load Balancer (CLB) is a service for distributing traffic among multiple cloud servers. Cloud Load Balancer can expand the service capacity of application systems externally through traffic distribution and enhance the availability of application systems by eliminating single points of failure.
For purchasing and configuring a load balancer, please refer to Cloud Load Balancer - Quick Start Guide.
Cloud Load Balancer has the following advantages:
- High Performance of Single Cluster
A set of CLB clusters consists of multiple physical servers, with availability reaching up to 99.95%. The cluster system also features the functions of removing faulty instances and selecting healthy instances to ensure the normal operation of backend server businesses. - Safety and Stability
CLB relies on the Great Wall distributed defense system to defend against the vast majority of network attacks (such as DDoS attacks), achieving second-level cleansing for traffic attacks, greatly avoiding situations such as IP blocking and bandwidth saturation.
Public Gateway
A public gateway is a cloud server with forwarding capabilities enabled. Cloud servers in a private network without public IPs can access the internet through public gateways located in different subnets. The public gateway server performs source address translation for public network traffic. All traffic from other cloud servers accessing the internet passes through the public gateway, with their IP addresses being converted to the IP address of the public gateway server.
For configuring the public gateway, please refer to Configure Public Gateway.