Help Center/ Cloud Container Engine/ Drawer/ Configuration Reference/ Cluster/ Network/ Non-Translated CIDR Blocks for External Communication
Updated on 2025-06-13 GMT+08:00

Non-Translated CIDR Blocks for External Communication

In a CCE cluster using the VPC network model, if a container in the cluster needs to access external networks, the source pod IP address must be masqueraded as the IP address of the node where the pod resides through SNAT. After the configuration, the node will not use SNAT in the CIDR block by default.

By default, nodes in a cluster do not perform SNAT on packets destined for 10.0.0.0/8, 172.16.0.0/12, or 192.168.0.0/16 that is detected by yangtse as a private CIDR block. Instead, these packets are directly transferred using the upper-layer VPC. (The three CIDR blocks are considered as internal networks in the cluster and are reachable at Layer 3 by default.)

Value Range

Standard CIDR blocks, which must be unique

Default Value

10.0.0.0/8,172.16.0.0/12,192.168.0.0/16

Modifiable

Yes

Scope

CCE standard clusters using the VPC model

Suggestions

Unless otherwise specified, keep the default settings.

To enable cross-node pod access, the CIDR block of the node where the target pod runs must be added.

Similarly, to enable cross-ECS pod access in a VPC, the CIDR block of the ECS where the target pod runs must be added.