Moving from the physical to virtual, applications, network policies, and the network administrator (NA) and server administrator (SA) roles are getting continuously overlapped, where the network edge is now virtual and has moved into the host, that is, the ESXi server. This changes the distinct boundary between the SA and NA roles.

Where physical machines were once just plugged into a switch, and the switch port configured by a network administrator, the SA can now create and deploy multiple hosts in a fraction of the time. And while the host life cycle has changed significantly, the same management policies need to apply in both cases, which means that access lists, VLANs, port security, and many more parameters need to be consistent. The challenge for SAs is to take advantage of the flexibility of virtualization while conforming to organizational policy.

The challenge for NAs is to maintain control over the network traffic and the access ports that are running over hardware that they don't directly control. Have a look at the following diagram for more details:

Specific benefits of the Nexus 1000V switch that help address these challenges are as follows:

• Policy-based configuration: This signifies a real-time configuration of network, storage, and security services. SA's efficiency and flexibility can be rapidly improved using the policy-based configuration as it introduces a VM-centric management.
• Mobile security and network policy: When you perform a live migration such as vMotion, it moves the policy as well with the VM for a persistent network. In that way, vMotion won't affect the VM traffic counters.
• Nondisruptive management model: Management and operations can come together in a single line for VMs' connectivity in the data center. Operational consistency and visibility is well maintained throughout the network.