Skip to main content
POST
Enable IPv6 on a subnet
Requires the IAM action network:UpdateSubnet. See NETWORK permissions for the full list, what each one covers, and an example policy.

Authorizations

Authorization
string
header
required

An OAuth 2.0 bearer token, sent as Authorization: Bearer <token>. This is the recommended way to authenticate.

Get one by exchanging a service account's access key pair at POST /v1/oauth/token with grant_type=client_credentials. It is the standard client-credentials grant, so any OAuth-aware library will obtain and refresh it for you.

Tokens last an hour by default. The same access key pair is separately your AWS SigV4 credential for the S3-compatible object endpoint, which speaks nothing else.

Path Parameters

subnet_id
string<uuid>
required

Subnet ID

Body

application/json

Provide allocate_cidr_ipv6 as true or a nonempty cidr_ipv6. Existing IPv6 ranges cannot be replaced.

allocate_cidr_ipv6
boolean
default:false
required

Allocate a free /64 from the VPC IPv6 range. Can be enabled after creation. Every existing and new interface receives an IPv6 /96 and its first /128 automatically. NAT gateways hosted here also receive a public IPv6 address from the regional pool. Updating hosted gateways requires UpdateNATGateway permission and public IPv6 quota.

cidr_ipv6
string

An aligned /64 inside the VPC IPv6 range. Can be added later; cannot replace an existing range. Mutually exclusive with allocate_cidr_ipv6.

Example:

"2a13:9500:1a6:100::/64"

copy_ipv4_security_rules
boolean
default:true

When enabling IPv6, copy equivalent rules in security groups used by this subnet's interfaces. Copies 0.0.0.0/0 to ::/0 and security-group references, preserving protocol, ports and direction. Restricted IPv4 CIDRs are not widened. Existing IPv6 equivalents are not duplicated. Changes affect every interface sharing these groups. Requires CreateSecurityGroupRule permission and available rule quota. Only accepted with allocate_cidr_ipv6 or cidr_ipv6.

ipv6_routing
enum<string>
default:match_ipv4

When enabling IPv6, optionally add ::/0 to the subnet's route table. match_ipv4 follows an IPv4 internet-gateway or NAT-gateway default route, using the same target. A NAT gateway must already have IPv6 enabled on its hosting subnet, or be hosted in the subnet being enabled. No IPv4 default route leaves IPv6 routing unchanged. Existing IPv6 default routes are always preserved. Egress-only gateways cannot provide ULA internet access; use a NAT gateway, or a public IPv6 floating IP with an internet-gateway route. Changes affect every subnet sharing the route table and require CreateRoute permission; creating an egress-only gateway also requires CreateEgressOnlyGateway permission. Only accepted with allocate_cidr_ipv6 or cidr_ipv6.

Available options:
match_ipv4,
unchanged,
internet_gateway,
nat_gateway,
egress_only_gateway

Response

IPv6 enabled

subnet
object
required