kubernetes/kops · error

error modifying AssignIPv6AddressOnCreation: %w

Error message

error modifying AssignIPv6AddressOnCreation: %w

What it means

ModifySubnetAttribute failed while toggling AssignIpv6AddressOnCreation on the subnet; the wrapped error is the AWS EC2 response (permissions or subnet state).

Source

Thrown at upup/pkg/fi/cloudup/awstasks/subnet.go:308

				Ipv6CidrBlock: e.IPv6CIDR,
				SubnetId:      e.ID,
			}

			_, err := t.Cloud.EC2().AssociateSubnetCidrBlock(ctx, request)
			if err != nil {
				return fmt.Errorf("error associating subnet cidr block: %v", err)
			}
		}
	}

	if a == nil || changes.AssignIPv6AddressOnCreation != nil {
		request := &ec2.ModifySubnetAttributeInput{
			SubnetId:                    e.ID,
			AssignIpv6AddressOnCreation: &ec2types.AttributeBooleanValue{Value: e.AssignIPv6AddressOnCreation},
		}
		_, err := t.Cloud.EC2().ModifySubnetAttribute(ctx, request)
		if err != nil {
			return fmt.Errorf("error modifying AssignIPv6AddressOnCreation: %w", err)
		}
	}

	if changes.ResourceBasedNaming != nil {
		hostnameType := ec2types.HostnameTypeIpName
		if *changes.ResourceBasedNaming {
			hostnameType = ec2types.HostnameTypeResourceName
		}
		request := &ec2.ModifySubnetAttributeInput{
			SubnetId:                       e.ID,
			PrivateDnsHostnameTypeOnLaunch: hostnameType,
		}
		_, err := t.Cloud.EC2().ModifySubnetAttribute(ctx, request)
		if err != nil {
			return fmt.Errorf("error modifying hostname type: %w", err)
		}

		if fi.ValueOf(e.CIDR) == "" {

View on GitHub (pinned to 4c8573c808)

Solutions

1. Check ec2:ModifySubnetAttribute permissions
2. Verify the subnet exists and is in a modifiable state, then retry

When it happens

Trigger: Thrown at upup/pkg/fi/cloudup/awstasks/subnet.go:308 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of kubernetes/kops@4c8573c808 (2026-09-05). Data as JSON: /api/errors/e2fb5b672449c591. Report an issue: GitHub.