This Month at Acrodex:

Feature:

Root Out Network Problems

By Reid Nilson, Senior Systems Engineer, Acrodex Integrated Network and Security Solutions

One of the main concerns of my clients has been network visibility.  Many times network issues can’t be effectively investigated because the tools aren’t enabled to allow the network operations staff to determine the root cause of network problems.  Server virtualization has amplified these problems as network devices like switches disappear into a hypervisor and can no longer be managed.

Cisco has introduced a solution to this problem with the Nexus 1000V virtual switch.  The Nexus 1000V runs the same NX-OS operating system as the hardware Nexus platforms giving the administrator a common platform to administer. 

The Nexus 1000V supports all the common network tools found in the Cisco Nexus platform like ERSPAN and SNMP including the powerful Netflow application.  Netflow allows a granular look at network traffic including source and destination IPs, source and destination ports and protocols allowing a detailed look at current traffic patterns.  If a trouble ticket comes in regarding slow network it is easy to open the Netflow collector and determine what applications or users are consuming network bandwidth quickly and easily.

Another issue is administrative separation.  In traditional operations the network administrator configures a switch port and the server administrator connects the server to the provided switch port. In a virtualized environment the server administrator is now responsible for switch configuration in addition to provisioning servers.  With the Nexus 1000V there is now the separation between the network and server, the network administrator configures the port on the Nexus 1000V and the server administrator just selects the provisioned network when creating a virtual machine.  The server administrator does not need to worry about VLANs or other network configuration items when creating a virtual machine.

So how does it work? There are two major components of the Nexus 100V, the Virtual Supervisor Module (VSM) which is deployed as a virtual machine on an ESXi host and the Virtual Ethernet Module (VEM) which is deployed as a module into an ESXi hypervisor.  The VEM works as a virtual linecard on the VSM which pushes out configuration to the VEM line cards.  To administer the 1000V a standard NX-OS command line interface is used.

The Nexus 1000V can be an invaluable addition to any network as it provides unmatched administrative flexibility and visibility into the traffic flowing across the network.  The VSM and VEM components can be installed on any vSphere 4.0 deployment with Enterprise Plus and is licensed on a per processor count basis.  

Reid Nilson is a Senior Systems Engineer at Acrodex.  He performs network design and network implementation for Acrodex's clients and is currently focusing on Unified Communications and Data Centre switching.