Network Resource

This topic falls into the following parts:

L2 network resources
L3 network resources
L3 network architecture model
Dedicated networks
Route resources
SDN controller
Network usage procedure
Network protocol

L2 Network Resources

L2 network resources include L2 networks and VXLAN pools.

An L2 network corresponds to a layer 2 broadcast domain. This L2 network supports multiple network types, such as L2NoVlanNetwork, L2VlanNetwork, VxlanNetwork, and HardwareVxlanNetwork.
L2NoVlanNetwork and L2VlanNetwork is a group that must be identical to the configurations of compute node ports on the switch sides.
Both VXLAN Pool and VxlanNetwork with the software SDN type provide the VxlanNetwork configurations. Before you use VxlanNetwork, create a VXLAN pool first. Then, create VxlanNetwork by specifying or randomly choosing VNIs.
Both VXLAN Pool and HardwareVxlanNetwork with the hardware SDN type provide the HardwareVxlanNetwork configurations. Before you use HardwareVxlanNetwork, create a VXLAN pool first. Then, create HardwareVxlanNetwork by specifying or randomly choosing VNIs.

L3 Network Resources

An L3 network can serve as a sub-resource of the L2 network. Mainly based on the L2 network, the L3 network provides the network configurations for VM instances, including the IP range, gateway, DNS, and network service.

L3 Network Architecture Model

The Cloud supports two L3 network architecture models: flat network and VPC network.

Dedicated Networks

Dedicated networks include management networks and flow networks. Note that you cannot create VM instances by using dedicated networks.

Route Resources

ZStack Cloud provides network services for VM instances by using custom Linux VM instances to serve as routing devices. Related route resources mainly include VPC vRouters, VPC HA groups, vRouter images, and vRouter offerings.

SDN Controller

By adding SDN controllers, you can take over the SDN networks of hardware switches on the Cloud to lower the network latency and improve the VXLAN network performance.

Network Usage Procedure

You need to first create an L2 network, use the L2 network to create an L3 network, and then use these networks to provide multiple network services.

Network Protocol

ZStack Cloud public network, flat network, and VPC network support two network protocols: IPv4 and IPv6. You can create an IPv4 network, an IPv6 network, or an IPv4+IPv6 network as needed.

L2 Network

What is L2 Network?

An L2 network is a layer 2 broadcast domain used for layer 2 isolation. Generally, L2 networks are identified by names of devices on the physical network.

VLAN, VXLAN, and SDN can be used as an L2 network.
An L2 network is used to provide layer 2 isolation for an L3 network.

L2 Network Types

The following four types of L2 networks are supported:

L2NoVlanNetwork
- You must specify the NIC name of the host.
- The hosts in the cluster to which the L2 network is attached must have NICs that share the same name.
- When the data packets of VM instances flow out of the host NIC and reach the physical switch, the data packets are not flagged with VLAN tags. Note that the physical switch must be in VLAN Access mode.
- If you create an L2 network of the L2NoVlanNetwork type, a network bridge is created based on the specified host NIC.
L2VlanNetwork
- You must specify the host NIC name and VLAN ID.
- The hosts in the cluster to which the L2 network is attached must have NICs that share the same name.
- When the data packets of VM instances flow out of the host NIC and reach the physical switch, the data packets are tagged with the specified VLAN ID.
- If you create an L2 network of the L2VlanNetwork type, a VLAN device is created based on the specified VLAN ID and then a network bridge is created based on the VLAN device.
- If you attach an L2 network of the L2NoVlanNetwork type and an L2 network of the L2VlanNetwork type or attach multiple L2 networks of the L2VlanNetwork type to a cluster, the physical switch NIC must be in Trunk mode. Besides, the VLAN ID in use must be contained in the Trunk VLAN configurations.
VxlanNetwork
- Virtual Extensible LAN (VXLAN) is an overlay technology that allows for the creation of overlaying L2 networks. This technology can support a maximum of 16 million logical networks.
- VxlanNetwork is an implementation of the software-based VXLAN technology.
- If you create an L2 network of the VxlanNetwork type, you must specify a software SDN-based VXLAN pool. The L2 network must correspond to a VNI in the pool.
- The VTEP IPs of the hosts in the cluster to which the L2 network of the VxlanNetwork type is attached must belong to the specified VXLAN pool.
- When the data packets of VM instances flow out of the host, the host encapsulates VXLAN messages to the data packets and then sends the encapsulated data to the physical switch.
HardwareVxlanNetwork
- Virtual Extensible LAN (VXLAN) is an overlay technology that allows for the creation of overlaying L2 networks. This technology can support a maximum of 16 million logical networks.
- HardwareVxlanNetwork is a solution to the integration with third-party hardware SDN.
- If you create an L2 network of the HardwareVxlanNetwork type, you must specify a hardware SDN-based VXLAN pool. The L2 network must correspond to a VNI in the pool.
- When the data packets of VM instances flow out of the host NICs and reach the distributed virtual switches, the data packets are flagged with the specified VLAN ID. The VLAN ID is mapped with VXLAN ID based on the SDN controlled that you add to the Cloud.

Note:

In CentOS 7, the NIC name in the ethX format will be changed after the system reboots. In addition, the NIC sequence will also be randomly changed. We recommend that you change the NIC name of each compute node (especially for VM instances with multiple NICs) to a non-ethX format, such as em01.

L2 Network | Cluster | L3 Network | VM Instance

The relationship between an L2 network and a cluster, an L3 network, a VM instance is as follows:

If you attached an L2 network to a cluster whereas the L2 network was not attached to a host, you could not add the host to the cluster.
If you did not attach an L2 network to a cluster and the L2 network was not attached to a host, you could not attach the L2 network to the cluster.
If you attached an L2 network to a host whereas the corresponding L2 network devices were inconsistently connected to other hosts in a cluster, note that the VM IP that you created would not work properly.
If you delete an L2 network, the corresponding L3 networks and VM NICs that are using these networks will also be deleted.
If you delete an L2 network, the VPC vRouter and vRouter offering that use the L2 network will also be deleted.
If you delete an L2 public network, all network services that are using the network, such as VPC vRouter, vRouter offering, VIP, EIP, port forwarding, load balancing, IPsec tunnel, and Netflow will also be deleted.
You can create multiple L2 networks of the VxlanNetworks type by using a VXLAN Pool of the Software SDN type. These L2 networks can be applied to flat networks and VPC networks, respectively.
VM instances in an L2 network of the VxlanNetwork type cannot be accessed through the Internet. To access these VM instances through the Internet, use an EIP or port forwarding.
You can also create multiple L2 networks of the HardwareVxlanNetworks type by using a VXLAN Pool of the Hardware SDN type. These L2 networks can currently be applied to flat networks.
If you use a vSwitch of the OVS-DPDK type for an L2 network, you can use the L2 network to create only IPv4 VPC networks and provide corresponding network services.

Create an L2 Network

On the main menu of ZStack Cloud, choose Resource Center > Network Resource > L2 Network Resources > L2 Network. On the L2 Network page, click Create L2 Network. Then, the Create L2 Network page is displayed.

The following lists the L2 networks that you can create:

Create an L2NoVlanNetwork.
Create a VxlanNetwork.
Create an L2VlanNetwork.
Create a HardwareVxlanNetwork.

Create an L2NoVlanNetwork

Set the following parameters:

Zone: By default, the current zone is displayed.
Name: Enter a name for the L2 network.
The L2 network name must be 1 to 128 characters in length and can contain Chinese characters, letters, digits, hyphens (-), underscores (_), periods (.), parenthesis (), colons (:), and plus signs (+).
Description: Optional. Enter a description for the L2 network.
Type: Select L2NoVlanNetwork.
vSwitch Type: The vSwitch type of the L2 network, including Linux Bridge and OVS-DPDK.
- If you select Linux Bridge, you can choose whether to enable SR-IOV.
  - By default, SR-IOV is disabled. If you disable SR-IOV for an L2 network, this feature is disabled for the L3 network created from this L2 network.
  - If you enable SR-IOV for an L2 network, this feature is enabled for the L3 network created from this L2 network.
  - Before you enable SR-IOV, make sure that VF NICs are generated from the physical NICs used by the L2 network.
- If you select OVS-DPDK, the SR-IOV option is not displayed.
Note:
- Linux Bridge vSwitches support all types of L2 networks and SR-IOV.
- OVS-DPDK vSwitches support only L2 networks of the L2VlanNetwork and L2NOVlanNetwork types and do not support SR-IOV.
- OVS-DPDK vSwitches occupy 4 GB huge pages of each host in a cluster. If you create a vSwitch of the OVS-DPDK type and attach the vSwitch to a cluster, make sure that the memory of the hosts in the cluster is sufficient.
Cluster: Optional. Select the cluster to be attached.
Note:
- You can attach a cluster when you create an L2NoVlanNetwork or after you create the L2 network.
- If an L2 network is not attached to a cluster, you cannot use the L2 network to create VM instances.
NIC Name: Enter a NIC name for the L2 network. For example, em01.

Create an L2VlanNetwork

Set the following parameters:

Zone: By default, the current zone is displayed.
Name: Enter a name for the L2 network.
The L2 network name must be 1 to 128 characters in length and can contain Chinese characters, letters, digits, hyphens (-), underscores (_), periods (.), parenthesis (), colons (:), and plus signs (+).
Description: Optional. Enter a description for the L2 network.
Type: Select L2VlanNetwork.
vSwitch Type: The vSwitch type of the L2 network, including Linux Bridge and OVS-DPDK.
- If you select Linux Bridge, set the following parameters:
  - VLAN ID: Specify a VLAN ID that matches the actual network configurations. Valid values: 1 to 4094.
  - SR-IOV: Optional. Choose whether to enable SR-IOV.
    - By default, SR-IOV is disabled. If you disable SR-IOV for an L2 network, this feature is disabled for the L3 network created from this L2 network.
    - If you enable SR-IOV for an L2 network, this feature is enabled for the L3 network created from this L2 network.
    - Before you enable SR-IOV, make sure that VF NICs are generated from the physical NICs used by the L2 network.
- If you select OVS-DPDK, set the following parameters:
  - VLAN ID: Specify a VLAN ID that matches the actual network configurations. Valid values: 1 to 4094.
Note:
- Linux Bridge vSwitches support all types of L2 networks and SR-IOV.
- OVS-DPDK vSwitches support only L2 networks of the L2VlanNetwork and L2NOVlanNetwork types and do not support SR-IOV.
- OVS-DPDK vSwitches occupy 4 GB huge pages of each host in a cluster. If you create a vSwitch of the OVS-DPDK type and attach the vSwitch to a cluster, make sure that the memory of the hosts in the cluster is sufficient.
Cluster: Optional. Select the cluster to be attached.
Note:
- You can attach a cluster when you create an L2NoVlanNetwork or after you create the L2 network.
- If an L2 network is not attached to a cluster, you cannot use the L2 network to create VM instances.
NIC Name: Enter a NIC name for the L2 network. For example, em01.

Create a VxlanNetwork

Set the following parameters:

Zone: By default, the current zone is displayed.
Name: Enter a name for the L2 network.
The L2 network name must be 1 to 128 characters in length and can contain Chinese characters, letters, digits, hyphens (-), underscores (_), periods (.), parenthesis (), colons (:), and plus signs (+).
Description: Optional. Enter a description for the L2 network.
Type: Select VxlanNetwork.
vSwitch Type: The vSwitch type of the L2 network. Only Linux Bridge is supported.
VXLAN Pool: Select a VXLAN pool of the software SDN type.
Note:
- Before you can create a VxlanNetwork, create a VXLAN pool of the software SDN type.
- For more information, see Create Software-SDN VXLAN Pool.
VNI: Optional. Select a specified VNI in the VXLAN pool.
If not specified, the Cloud allocates a VNI randomly.

Create a HardwareVxlanNetwork

Set the following parameters:

Zone: By default, the current zone is displayed.
Name: Enter a name for the L2 network.
The L2 network name must be 1 to 128 characters in length and can contain Chinese characters, letters, digits, hyphens (-), underscores (_), periods (.), parenthesis (), colons (:), and plus signs (+).
Description: Optional. Enter a description for the L2 network.
Type: Select HardwareVxlanNetwork.
vSwitch Type: The vSwitch type of the L2 network. Only Linux Bridge is supported.
VXLAN Pool: Select a VXLAN pool of the hardware SDN type.
Note:
- Before you can create a HardwareVxlanNetwork, create a VXLAN pool of the hardware SDN type.
- For more information, see Create Hardware-SDN VXLAN Pool.
VNI: Optional. Select a specified VNI in the VXLAN pool.
If not specified, the Cloud allocates a VNI randomly.