Help Center/ Virtual Private Cloud/ User Guide/ VPC and Subnet/ VPC Connectivity Options/ Connecting VPCs to On-Premises Data Centers
Updated on 2025-09-24 GMT+08:00
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Connecting VPCs to On-Premises Data Centers

Connecting a Single VPC to an On-Premises Data Center

You can use Direct Connect or VPN to connect a VPC to an on-premises data center.

Connecting VPCs to an On-Premises Data Center provides details about different network services.

Before connecting a VPC to an on-premises data center, you need to plan their CIDR blocks in advance to ensure that the VPC CIDR block does not overlap with the on-premises CIDR block, or communications may fail.

VPN provides an encrypted, Internet-based channel that connects an on-premises data center and the cloud.

For details, see Configuring Enterprise Edition S2C VPN to Connect an On-premises Data Center to a VPC.

In Figure 1, some workloads have been migrated to a VPC (VPC-A), and some workloads are still running on on-premises servers. With a VPN connection, on-premises servers can quickly access the cloud resources in the VPC. Compared with Direct Connect, VPN is easier to configure and cost-effective.
Figure 1 Connecting a VPC to an on-premises data center using VPN

Direct Connect establishes a dedicated network connection between an on-premises data center and the cloud.

For details, see Accessing a VPC over a Direct Connect Connection and Using BGP to Route Traffic.

In Figure 2, some workloads are running in a VPC (VPC-A) on the cloud, and some are running in the on-premises data center. A Direct Connect connection connects the on-premises data center to the cloud. Direct Connect connections are faster and more stable than VPN connections.
Figure 2 Connecting a VPC to an on-premises data center using Direct Connect

Connecting Multiple VPCs in the Same Region to an On-Premises Data Center

To connect multiple VPCs in a region to an on-premises data center, you can use Direct Connect or VPN to connect the data center to a VPC, and then use VPC Peering or Enterprise Router to connect all VPCs. In this way, the on-premises data center can access all the VPCs.

Compared with VPN, Direct Connect establishes a dedicated connection that enables faster, more secure data transmission. VPN is more cost-effective. To reduce network costs, you can use VPN instead of Direct Connect. Connecting VPCs to an On-Premises Data Center provides details about different network services.
To connect VPCs to an on-premises data center, you need to plan their CIDR blocks in advance. Note the following:
  • Ensure that the VPC CIDR blocks do not overlap with the on-premises CIDR block, or communications may fail.
  • Ensure that the VPC CIDR blocks do not overlap, or communications may fail.

With VPC Peering, you can peer two VPCs in the same region, no matter whether they are in the same account or different accounts. VPC Peering can work with Direct Connect or VPN to enable your on-premises data center to access multiple VPCs.

For details, see Connecting an On-Premises Data Center to Multiple VPCs that Need to Communicate with Each Other.

In Figure 3, some workloads are running in two VPCs (VPC-A and VPC-B) in a region, and some workloads are running in the on-premises data center. The on-premises data center connects to a VPC (VPC-B) over a Direct Connect connection, and VPC-A and VPC-B are connected over a VPC peering connection. In this way, the on-premises data center can access both VPC-A and VPC-B.

Figure 3 Connecting an on-premises data center to VPCs using Direct Connect and VPC Peering

You can use VPN or Direct Connect to connect an on-premises data center to a VPC, and then use an enterprise router to connect multiple VPCs if there are in the same region.

In Figure 4, some workloads are running in two VPCs (VPC-A and VPC-B) in a region, and some workloads are running in the on-premises data center. The two VPCs and global DC gateways are attached to an enterprise router in the same region, so that the two VPCs can communicate with each other and also with the on-premises data center.

In this example, two Direct Connect connections are deployed to balance loads, improving the network performance and reliability. When both connections work normally, the network transmission capability is greatly improved. If one connection becomes faulty, the other connection can take over services, and your on-premises data center can still access the VPCs.

Figure 4 Connecting an on-premises data center to VPCs in the same region using Direct Connect and Enterprise Router

Connecting Multiple VPCs in Different Regions to On-Premises Data Centers

To connect multiple VPCs in different regions to on-premises data centers, you can use Direct Connect or VPN to connect each on-premises data center to a VPC, and then use a cloud connection or central network to connect all VPCs.

Compared with VPN, Direct Connect establishes a dedicated connection that enables faster, more secure data transmission. VPN is more cost-effective. To reduce network costs, you can use VPN instead of Direct Connect. Connecting VPCs to an On-Premises Data Center provides details about different network services.
To connect VPCs to an on-premises data center, you need to plan their CIDR blocks in advance. Note the following:
  • Ensure that the VPC CIDR blocks do not overlap with the on-premises CIDR block, or communications may fail.
  • Ensure that the VPC CIDR blocks do not overlap, or communications may fail.

You can attach VPCs and Direct Connect global DC gateways in the same region to an enterprise router, and then add the enterprise routers in different regions to a central network. In this way, VPCs in different regions can communicate with on-premises data centers in multiple cities. Compared with a cloud connection, using a central network features a simpler architecture and higher scalability.

In Figure 5, VPCs and global DC gateways in each region are attached to different enterprise routers, so the on-premises data center in each city can access the VPCs in the corresponding region. Then the two enterprise routers (ER-A and ER-C) are connected over a central network. In this way, the three VPCs (VPC-A, VPC-B, and VPC-C) and two on-premises data centers (IDC-A and IDC-C) are on the same cloud network and can communicate with each other. In this solution, only the enterprise router in each region is added to the central network, simplifying the network architecture. Also, with global DC gateways attached to enterprise routers, VPCs can share Direct Connect connections to communicate with the on-premises data centers. Route learning of enterprise routers eliminates complex configurations and simplifies maintenance.
Figure 5 Connecting on-premises data centers to VPCs across regions using a central network

Connecting a VPC to the Network of a Peer Vendor Cloud

The connection between a VPC and a peer vendor cloud works the same way as that between a VPC and an on-premises data center. You can regard a peer vendor cloud as an on-premises data center to connect to it using Direct Connect or VPN for multi-cloud networking.

VPN can provide an encrypted, Internet-based channel to connect a VPC to a peer vendor cloud network.

In Figure 6, some workloads are deployed in the VPC in region A, and some workloads are still running in the VPC in region A on a peer vendor cloud. With VPN, resources on Huawei Cloud and peer vendor cloud can communicate over an encrypted, Internet-based channel. Compared with Direct Connect, VPN is easier to configure and cost-effective.
Figure 6 Connecting a VPC to a peer vendor cloud using VPN

The VPN and VPC names in the figure are for reference only. The actual cloud service names are subject to the peer vendor.

Direct Connect can establish a dedicated network connection between a VPC and a peer vendor cloud network.

In Figure 7, some workloads are deployed in the VPC in region A on Huawei Cloud, and some are deployed in the VPC in region A on the peer vendor cloud. A Direct Connect connection connects the networks of Huawei Cloud and the peer vendor cloud. Direct Connect connections are faster and more stable than VPN connections.
Figure 7 Connecting a VPC to a peer vendor cloud using Direct Connect

The Direct Connect and VPC names in the figure are for reference only. The actual cloud service names are subject to the peer vendor.

Connecting a VPC to a User Client Network

If a user client wants to access Huawei Cloud through VPN, SSL VPN is recommended. SSL VPN uses the SSL protocol to let remote users securely access enterprise intranet resources in an encrypted manner. For details, see Configuring P2C VPN to Connect Mobile Terminals to a VPC.

In Figure 8, a user can remotely access resources in a VPC from a PC, mobile phone, or tablet through a client application.

Figure 8 Connecting a VPC to a user client using VPN

If some applications are deployed in both Huawei Cloud and the IDC, both IPsec VPN and SSL VPN on the VPN gateway can be used to connect the VPC to the IDC and the user client network. In Figure 9, after the VPN connections are established, both the user client and the IDC can access the VPC, and also the user client and the IDC can communicate with each other.

Figure 9 Connecting a VPC, user client, and IDC using IPsec VPN and SSL VPN
Parent Topic: VPC Connectivity Options