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Updated on 2024-04-03 GMT+08:00

Which CIDR Blocks Are Available for the VPC Service?

The following table lists the private CIDR blocks that you can specify when creating a VPC. Consider the following when selecting a VPC CIDR block:
  • Number of IP addresses: Reserve sufficient IP addresses in case of business growth.
  • IP address range: Avoid IP address conflicts if you need to connect a VPC to an on-premises data center or connect two VPCs.
Table 1 lists the supported VPC CIDR blocks.
Table 1 VPC CIDR blocks


IP Address Range

Maximum Number of IP Addresses




Table 1 describes the primary IPv4 CIDR blocks available for a VPC. After a VPC is created, its primary CIDR block cannot be modified. If the primary CIDR block is insufficient, you can add a secondary IPv4 CIDR block for the VPC.

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