2.3. Logical Networks

A Logical Network is a way of representing networks in your data center that have the same connectivity properties. The logical network in a data center ensures that the hosts, manager and storage remain connected. When the data center is created, the management network is defined by default. However new logical networks, for example for data, storage, or display, can be defined by the administrator. In general, logical networks are assigned by functionality and physical topology. New networks, for example for data, storage, or display, can be added to enhance network speed and performance. In addition, other networks can be used to segregate virtual machine traffic from the management networks, or isolate traffic between groups of virtual machines in the same cluster.
Data Center Objects

Figure 2.15. Data Center Objects

For example, a data center may have the following networks,
  • Guest data network
  • Storage network access
  • Management network
  • Display network (for SPICE or VNC)


Do not change networking in a data center or a cluster if any hosts are running. This may make the host unreachable.

2.3.1. Logical Networks Properties

A logical network is assigned as a required resource of a cluster in a data center, and by extension all hosts in a cluster must have the same set of logical networks. The implementation itself may vary from host to host (IP and bonding properties). Therefore, to configure a network, define the logical network and then apply this network to the NIC on each host. By default the management network (rhevm) is defined for a data center. Red Hat Enterprise Virtualization platform allows you to use VLAN ID tagging and supports STP in logical networks

Table 2.12. Logical Network Properties

The name of the network belonging to the data center.
The description of the network.
STP Support, VLAN Tagging
STP support and VLAN tagging are optional attributes.