Nexus 1000V and Cisco VSG…..Critical Components Of a Virtualized Data Centre

As the Cisco investment in data centre probably shows, there’s a good chance that those huge sites brimming with expensive hardware and requiring a private power grid, are being challenged by the virtualised data centre. In fact what that really means is that all the server hardware runs on a hypervisor, (Vmware or Hyperv or Citrix Xen to name a few). Servers are Virtual machines, physically residing on large chassis servers and can contain hundreds sometimes 1000s of VMs on one physical server.

There are numerous issues that this presents us, and both Cisco and Vmware themselves have their own solution. The Cisco solution is the Nexus 1000v, and it can physically run as a VM inside the Vmware ESXI instance (roughly speaking) or it can run on a Cisco device called a 1010-x, which Cisco call a Virtual Services Appliance ….but crucially presenting a command line and commands that network engineers know and can manipulate rather than a server based front end that may be a little more familiar to server engineers.

The Nexus 1000V, represents virtual ethernet interfaces in exactly the same way as a physical switch, presents physical (ethernet) interfaces……but the traffic is switched in a virtual environment, which then allows, through a Cisco technology called vPath, to “chain” that 1 traffic flow through a number of “services”. Firewalling at layer 2(VSG), firewalling at L3 (N1000vASA), and compression/acceleration (vWAAS).

However, high level explanation is fine…….but as engineers we get paid to install, configure, support and troubleshoot installations, like the one I have described above. Of course the first step is to understand the concepts, but it’s low level skills that get our bills paid.

Now we’ve covered the concepts…..a little, and I encourage a lot more background reading on how the Cisco Data Centre model fits together, we can get to configuration, verification and troubleshooting commands.

Starting with the Nexus 1000v and VSG, mainly because the problems I have faced, whilst studying for Cisco Data Centre exams, are that in the Cisco Data Centre model are 2* Nexus 7Ks, 2* Nexus 5Ks. I have heard it said that to get “hands-on” that costs a million dollars…….not sure if that’s correct, but this is expensive equipment.

I have developed my own hands on lab….which provides a lot of the Cisco DC syllabus (but not all) and the N1000v and VSG have usable free versions which are freely downloadable …..more on that later

Instant Command Recall……..the networking skill that really matters!

Neil Meadows