---
title: vmnet_nat66_prefix_key
framework: vmnet
role: symbol
role_heading: Global Variable
platforms: [Mac Catalyst 13.0+, macOS 10.15+]
path: vmnet/vmnet_nat66_prefix_key
---

# vmnet_nat66_prefix_key

The IPv6 prefix string to use with vmnet shared mode.

## Declaration

```swift
let vmnet_nat66_prefix_key: UnsafePointer<CChar>
```

## Discussion

Discussion Use this with the VMNET_SHARED_MODE; the prefix must be a Unique Local Addresses (ULA) and start with one of the ULA prefixes such as fd00::/8. For more information on ULAs, see RFC-4193.

## See Also

### Customizing a network configuration

- [vmnet_network_configuration_ref](vmnet/vmnet_network_configuration_ref.md)
- [vmnet_network_configuration_add_dhcp_reservation(_:_:_:)](vmnet/vmnet_network_configuration_add_dhcp_reservation(_:_:_:).md)
- [vmnet_network_configuration_add_port_forwarding_rule(_:_:_:_:_:_:)](vmnet/vmnet_network_configuration_add_port_forwarding_rule(_:_:_:_:_:_:).md)
- [vmnet_network_configuration_disable_router_advertisement(_:)](vmnet/vmnet_network_configuration_disable_router_advertisement(_:).md)
- [vmnet_network_configuration_disable_nat66(_:)](vmnet/vmnet_network_configuration_disable_nat66(_:).md)
- [vmnet_network_configuration_disable_nat44(_:)](vmnet/vmnet_network_configuration_disable_nat44(_:).md)
- [vmnet_network_configuration_disable_dns_proxy(_:)](vmnet/vmnet_network_configuration_disable_dns_proxy(_:).md)
- [vmnet_network_configuration_disable_dhcp(_:)](vmnet/vmnet_network_configuration_disable_dhcp(_:).md)
- [vmnet_nat66_prefix_length_key](vmnet/vmnet_nat66_prefix_length_key.md)
- [vmnet_port_forwarding_rule_get_details(_:_:_:_:_:)](vmnet/vmnet_port_forwarding_rule_get_details(_:_:_:_:_:).md)
- [vmnet_network_configuration_set_external_interface(_:_:)](vmnet/vmnet_network_configuration_set_external_interface(_:_:).md)
- [vmnet_network_configuration_set_ipv4_subnet(_:_:_:)](vmnet/vmnet_network_configuration_set_ipv4_subnet(_:_:_:).md)
- [vmnet_network_configuration_set_ipv6_prefix(_:_:_:)](vmnet/vmnet_network_configuration_set_ipv6_prefix(_:_:_:).md)
- [vmnet_network_configuration_set_mtu(_:_:)](vmnet/vmnet_network_configuration_set_mtu(_:_:).md)
- [vmnet_network_get_ipv6_prefix(_:_:_:)](vmnet/vmnet_network_get_ipv6_prefix(_:_:_:).md)