[[["易于理解","easyToUnderstand","thumb-up"],["解决了我的问题","solvedMyProblem","thumb-up"],["其他","otherUp","thumb-up"]],[["很难理解","hardToUnderstand","thumb-down"],["信息或示例代码不正确","incorrectInformationOrSampleCode","thumb-down"],["没有我需要的信息/示例","missingTheInformationSamplesINeed","thumb-down"],["翻译问题","translationIssue","thumb-down"],["其他","otherDown","thumb-down"]],["最后更新时间 (UTC)：2025-07-21。"],[],[],null,["# Prepare for Hybrid Subnets connectivity\n=======================================\n\n|\n| **Preview**\n|\n|\n| This feature is subject to the \"Pre-GA Offerings Terms\" in the General Service Terms section\n| of the [Service Specific Terms](/terms/service-terms#1).\n|\n| Pre-GA features are available \"as is\" and might have limited support.\n|\n| For more information, see the\n| [launch stage descriptions](/products#product-launch-stages).\n\nThis page describes the tasks that you need to complete before you can\nuse Hybrid Subnets. Ensure that your source network and\nVirtual Private Cloud (VPC) network are ready for Hybrid Subnets\nconnectivity by completing the following steps.\n\nConnect a VPC network to a source network\n-----------------------------------------\n\nA hybrid subnet requires connectivity between a VPC network and\na source network. The connection must be one of the following types:\n\n- A pair of HA VPN tunnels\n- VLAN attachments for Dedicated Interconnect\n- VLAN attachments for Partner Interconnect\n\nFor help choosing a connection type, see\n[Choosing a Network Connectivity product](/network-connectivity/docs/how-to/choose-product).\n\nTo configure hybrid connectivity, see the following:\n\n- [Create an HA VPN gateway to a peer VPN gateway](/network-connectivity/docs/vpn/how-to/creating-ha-vpn)\n- [Create Dedicated Interconnect VLAN attachments](/network-connectivity/docs/interconnect/how-to/dedicated/creating-vlan-attachments)\n- [Create Partner Interconnect VLAN attachments](/network-connectivity/docs/interconnect/how-to/partner/creating-vlan-attachments)\n\nConfigure custom route advertisement\n------------------------------------\n\nWhen you configure hybrid connectivity, you create a Cloud Router.\nConfigure the Cloud Router's BGP session to\n[only advertise custom routes](/network-connectivity/docs/router/how-to/advertising-subnets#bgp-session). Don't add any routes now;\nin a later step, you add custom routes for each migrated VM.\n\nConfigure firewall rules\n------------------------\n\nTo ensure that Google Cloud virtual machine (VM) instances can communicate\nwith workloads in your source network and Google Cloud VMs that use the\nhybrid subnet's IP address range, do the following:\n\n- In Google Cloud, create ingress allow firewall rules or rules in\n firewall policies to allow all packets from the IP address range that is\n associated with the hybrid subnet.\n\n The [implied allow egress](/vpc/docs/firewalls#default_firewall_rules)\n firewall rule allows egress from Google Cloud VMs. If you've\n created egress deny firewall rules or egress deny rules in firewall policies,\n you'll need to create egress allow rules to permit packets to the IP address\n range that is associated with the hybrid subnet.\n\n You can scope firewall rules to specific VMs by using the target\n parameter of the rule. For more information, see:\n - [VPC firewall rules](/vpc/docs/firewalls)\n - [Firewall policies](/vpc/docs/firewall-policies-overview)\n- Configure firewalls in your source network in a similar way.\n\nConfigure source network routing\n--------------------------------\n\nTo prepare your source network for Hybrid Subnets connectivity,\ndo the following.\n\n### Enable proxy ARP for the source network\n\nEnable [proxy ARP](https://en.wikipedia.org/wiki/Proxy_ARP) for your source\nnetwork. For more information, see\n[Proxy ARP and Hybrid Subnets](/vpc/docs/hybrid-subnets#proxy-arp).\n\nFor information on enabling proxy ARP, see the documentation of your\nproxy ARP solution.\n\n### Advertise your hybrid subnet's IP address range\n\nConfigure your source network to advertise the primary internal IPv4 address\nrange of the VPC part of your hybrid subnet.\n\nWhat's next\n-----------\n\n- To learn more about Hybrid Subnets, see\n [About Hybrid Subnets](/vpc/docs/hybrid-subnets).\n\n- To migrate workloads from a source subnet to a VPC\n subnet, see [Create a hybrid subnet](/vpc/docs/create-hybrid-subnets)."]]
