IP addresses are divided into two categories: IPv4 and IPv6. IPv4 is widely used, but the network address resources are limited. IPv6 can solve the problem of limited network address resources well.
IPv4 Address
The cloud platform has two types of IPv4 addresses: private network IPv4 address and public network IPv4 address. If you do not take the initiative to unbind or replace, neither the private network IPv4 nor the public network IPv4 change.
Private Network IPv4 Address
The private network IPv4 address is the implementation form of the cloud platform's IPv4 private network services and cannot be accessed through the IPv4 Internet. Once each CVM instance is created, it is assigned a private network IPv4 address, which can be automatically allocated by the system. In the VPC environment, the private network IPv4 address can also be customized by users.
Attribute
- IPv4 private network services have user attributes and different users are isolated from each other; that is, by default, they cannot access another user's cloud service via the IPv4 private network.
- IPv4 private network services have regional attributes, and different regions are isolated from each other. That is, by default, cloud services and VPCs in different regions under the same account cannot be accessed through the IPv4 private network.
Applicable Scenario
The private network IPv4 address is applicable to the following scenarios:
- IPv4 private network access between CLB and CVM instances in the same VPC.
- IPv4 private network access between CVM instances in the same VPC.
- IPv4 private network access between CVM instances and other cloud services (such as TDB) in the same VPC.
Related Operations
- To obtain the private network IPv4 address of the instance and set DNS, see Obtaining the Private Network IP Address and Setting DNS.
- To modify the private network IPv4 address of a CVM instance in VPC, see Modifying Private Network IP Address.
Public Network IPv4 Address
Public network IPv4 addresses are divided into two categories: normal public IP and EIP, both of which can provide CVM with the ability to access or be accessed by IPv4 public networks.
Main Differences
The main differences between normal public IP and EIP are as follows:
| Comparison Items | Normal Public IP | EIP |
|---|---|---|
| Use Scenario | If you want the system to automatically assign a public network IP address when you create a CVM, and after the CVM is released, the normal public IP is released together without retaining the public network IP address, you can select a normal public IP. | If you want to use a public network IP address for a long time and bind it to the designated CVM based on business needs. You can select an EIP, which can be bound and unbound repeatedly. After the CVM is released, EIP still exists. |
| Ability to access/be accessed by the public network | As public IP addresses, they have the same ability to access and be accessed by the public network. | As public IP addresses, they have the same ability to access and be accessed by the public network. |
| How to Obtain | It is only allocated when the CVM is purchased. If it is not allocated when purchased, it cannot be obtained. | - Apply for EIP at the console. - Convert normal public IP to EIP. |
| Features | Consistent with the CVM lifecycle, after the CVM is released, the normal public IP is also released. | - Independently enjoyed IP resources can be bound and unbound with CVMs, NAT gateways, etc., at any time. - It can be released when no longer needed. |
| Quota | There is no fixed quota for the number of IPs, which is consistent with the quota for the available CVM. | Each account can apply for 20 IP addresses in each region. |
| Quota | For the quota of normal public IP (including normal public IP and EIP) bound to each CVM, see Limitations on Binding CVM. | For the quota of normal public IP (including normal public IP and EIP) bound to each CVM, see Limitations on Binding CVM. |
| Operation - Convert IP | It can be converted. For details, see Converting Normal Public IP to EIP. After a normal public IP is converted to an EIP, only the IP attributes change, and the IP address remains unchanged. |
EIP cannot be converted into normal public IP. |
| Operation - Release IP | If you no longer need a normal public IP, you can select More > IP/Network Interface > Refund Public Network IP to refund in the operation column of the. | It can be released on the EIP console. For details, see Releasing EIP. |
IPv6 Address
The IPv6 address of the cloud platform can be used as both an private network IPv6 address and a public network IPv6 address. By default, it is an private network IPv6 address. When the public network capability needs to be enabled, this address can be changed into a public network IPv6 address. If you do not take the initiative to release or reallocate, this IPv6 address does not
change.
Private Network IPv6 Address
The private network IPv6 address is the implementation form of the cloud platform's IPv6 private network service and cannot be accessed through the IPv6 Internet. When you create a CVM instance, you can choose to allocate an IPv6 address free of charge, which will be automatically allocated by the system or obtained after creation. In VPC environments, private network IPv6 addresses can also be customized by users.
Attribute
- IPv6 private network services have user attributes and different users are isolated from each other; that is, by default, they cannot access another user's cloud service via the IPv6 private network.
- IPv6 private network services have region attributes and different regions are isolated from each other; that is, by default, cloud services and VPCs in different regions under the same account cannot be accessed through the IPv6 private network.
Applicable Scenario
The private network IPv6 address is applicable to IPv6 private network access between CVM instances under the same VPC.
Public Network IPv6 Address
After the IPv6 address is opened to the public network, it has the ability to access the IPv6 public network and be accessed by the IPv6 public network as a public network IPv6 address.