How Abiquo networking works

Creating networks

Creating a network

When you create a network in private cloud

• If it is a private network, it is created in a virtual datacenter context
  
  • If it is an IPv4 address
    
    • The gateway address is automatically created
    • The VLAN tag is not allocated until the first VM is deployed
      
      • It will be allocated from the rack's VLAN range that should be configured in the switch or network management system
• If it is an external, public, or unmanaged network, it is created in a datacenter context
  
  • You enter a VLAN tag
    
    • This VLAN tag should be already configured in the switch or network management system
    • It should not be in the range of VLANs that the rack will use for private networks
    • For external and public networks, the VLAN tag must be configured in DHCP
• You can create an IP address or a range of addresses by entering the first address and the number of addresses to create
• The IPs in the network are added to the internal IP pool
  
  • For external or public network
    
    • IPs are marked as available/not available in the internal IP pool
  • For private network
    
    • All IPs are marked as available

Making a network the default VLAN for an enterprise

When you make an external network the default for an enterprise

• The default VLAN network ID is added to the enterprise limits for the datacenter

Creating a virtual datacenter

When you create a virtual datacenter for the enterprise

• The default enterprise network (e.g. external network) is set as the default for the virtual datacenter
• A default private network is created

Purchasing public IPs for a virtual datacenter

When you purchase public IPs for a virtual datacenter

• MAC addresses are generated for the network interfaces that will be used by these IPs

IP assignment

The IP assignment process has three main stages: configuration, deploy and power on.

Configuring a VM

When a new VM is created in Abiquo

• The configuration may include a network interface in any of the Abiquo networks
  
  • In VM configuration on the Network tab, the user can create a new IP address in a private or public network
  • The user can request an automatically generated IP address, to create a network interface
  • The user can select an existing IP address to create a network interface
  • For each network interface, Abiquo assigns a unique MAC address
    
    • For public networks, the MAC is generated when the NIC is purchased by the virtual datacenter
    • For external networks, the MAC is generated when the NIC is assigned to the virtual machine
    • For IPv6 networks, the MAC is used to generate the IP address
  • The MAC address is included in network configuration that is sent to the hypervisor

Deploying a VM

When the VM is deployed to a hypervisor

• If the user did not create a NIC, then Abiquo configures one in the default network (if it is not unmanaged)
• The Abiquo Server sends the network configuration to the DHCP Server as a DHCP lease
  
  • The IP address is the one assigned when the VM was configured (by the user or Abiquo)
  • The MAC address was assigned by Abiquo when the VM was configured
  • The lease may include other information, e.g. one-time API key for Chef configuration
  • The IP addresses assigned by the DHCP server are static
• If the VM is the first in the network
  
  • If it is a private network
    
    • Schedule resources and automatically select the VLAN tag (see below)
  • Else
    
    • Schedule resources using the VLAN tag reserved by the user when creating the network
  • Create a new VLAN for this network
    
    • in ESX, create a port group for the VLAN
    • in KVM, create a virtual bridge for the VLAN
• Otherwise, attach the NIC to an existing port group/virtual bridge, etc.

Powering on a VM when using DCHP

When a VM is powered on

1. It broadcasts a request for network configuration using DHCP
2. The hypervisor passes the request over the service network
   
   • The service network is a trunk connection between hypervisors and DHCP for VLAN networks
   • If you are using a DHCP Relay Server
     
     • the relay forwards the request to the DHCP Server
   • Otherwise
     
     • the DHCP Server receives the request directly
3. The DHCP Server sends a lease to the service network 
   
   • If you are using a DHCP Relay
     
     • the relay forwards the request to the VM
   • Otherwise
     
     • the VM receives the request directly over the service network
4. The VM can now use its network configuration

See Configuring DHCP and DHCP troubleshooting 

With DHCP Relay

VLAN Allocation

Abiquo will only automatically allocate VLAN tags for Abiquo private networks that are isolated within virtual datacenters within the configured range. You must configure VLAN tags in the switch with ports in "access mode" for connections to external, public and unmanaged networks.

Private Network VLAN Allocation

Abiquo automatically allocates private VLANs as part of the resource scheduling process. See VLAN Allocation