二层网络资源

VXLAN Pool

VXLAN Pool: A VXLAN pool is a collection of VXLAN networks established based on VXLAN Tunnel Endpoints (VTEPs). The VNI of each VXLAN network in a VXLAN pool must be unique.
  • Before you can use a VXLAN network, create a VXLAN pool in advance.
  • A VXLAN pool is only a collection of VXLAN networks and cannot be used to create L3 networks.
  • VXLAN pool supports two types of SDN: software SDN and hardware SDN.
    • Software SDN:
      • The VNI range of a software-SDN VXLAN pool can be 1-16777214.
      • Hosts in the cluster to which the software-SDN VXLAN pool is attached must have an IP address as a VXLAN tunnel endpoint (VTEP) in the specified CIDR.
        • Generally, a VTEP corresponds to a NIC IP of a compute node within a cluster. On the Cloud, you can configure a VTEP according to its CIDR. For example,
          • Assume that the NIC IP of a compute node is 10.12.0.8, the netmask is 255.0.0.0, and the gateway is 10.0.0.1. Then, the CIDR of the VTEP is 10.0.0.1/8.
          • Assume that the NIC IP of the compute node is 172.20.12.13, the netmask is 255.255.0.0, and the gateway is 172.20.0.1. Then, the CIDR of the VTEP is 172.20.0.1/16.
        • When a VXLAN pool is attached to a cluster, the IP address that is associated to the VTEP will be checked without checking physical L2 devices.
    • Hardware SDN:
      • Before you can create a hardware-SDN VXLAN pool, add an SDN controller to the Cloud in advance.
      • The VNI range of a hardware-SDN VXLAN pool depends on the distributed vSwitch to which an SDN controller corresponds.
      • The host NIC in the cluster to which the hardware-SDN VXLAN pool is attached must connect to a switch managed by the SDN controller.
      • If you use VCFC to configure hardware SDN, configure the mapping between VLAN and VXLAN on VCFC in advance.

二层网络

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.
The following four types of L2 networks are supported:
  1. 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.
  2. 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.
  3. 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.
  4. 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.