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To L2 or not to L2, that is the Question for VMotion:

This is a favorite question of mine (and a very contemporary topic), albeit asked in a different way;  Why do you need layer 2 for VMotion.  Those bearing the email signature of VCP, will be quick to show off their shiny new badge and tell you it is because of VMotion, because of a port group label, or some other VMware specific component.  In fact, there is a more fundamental reason.  It is called an ARP cache, IP Address, Default Gateway and DNS.  

Remember how hosts find each other – with IP a host looks to the IP address for the destination host, but remember we are speaking about L2 or to make it simple for this explanation, Ethernet.  This is accomplished by using the address resolution protocol (ARP) to bind a destination IP address with a destination MAC (because Ethernet is Ethernet and NOT IP – Pet peeve alert when someone refers to Ethernet as an IP network, but I digress).  Of course, the source host compares the destination IP with its own IP and mask, which determines whether you send the request to the default gateway – which in turn will proxy ARP for the destination host with its own MAC address, or to ARP on the local subnet.  To avoid a constant broadcast storm, clients cache this information for a period of time with the assumption that not much or nothing will change. 

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Role of Application Delivery Controllers in a Virtual Data Center

We all know that VMware based data center virtualization is here to stay and is quite rightly incorporated in enterprise and service provider application delivery infrastructure. Although many benefits are gained by migrating to a virtual data center, deploying a virtual data center infrastructure that solves your application delivery needs can be challenging. The most common challenge faced is related to application deployment i.e. how will administrators create virtual machines (VMs), deploy applications, provision traffic flows between virtual servers and Application Delivery Controllers (ADCs), and perform routine maintenance of applications in a timely manner to meet business objectives.

Today quite a few ADC vendors have provided fragmented solutions which increase complexity.  To realize the real advantage of virtual application delivery requires the application services to be integrated within the management environment of the virtual infrastructure and the virtualized data center. For example, in VMware’s case the vCenter will need the capability to provide appropriate controls for provisioning new VMs to the ADC, present views of traffic flows, and tools for automating change control associated with the application delivery framework.

 Today this challenge has been addressed by one such ADC and it simplifies delivery of applications, even if they are deployed in virtual environments.  Why?.. Because VMware has the capability to share compute resources among application loads and this next generation ADC enables sharing of the network bandwidth among network loads and provides vCenter-integrated tools and features to simplify application delivery.

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Introducing CIM Modeling Services

Collaborative Infrastructure Modeling (CIM)

We recently launched a new service capability out of our Customer Advocacy teams that provides a collaborative medium between facilities and IT operations.  For anyone who has tried to manage the design aspects of establishing a new data center infrastructure architecture, you know that some of the most painful moments come from “translating” between facilities and IT designs.  We’ve chosen to develop proposed infrastructure architectures using Google SketchUp which is freeware and incredibly easy to use.

Traditionally the physical design has been built using applications like Visio, AutoCad and BIM.  These applications are ideal if you need a very detailed blueprint to build against.  However, they tend to have large file sizes and are only accessible to specially trained individuals.  With SketchUp and the 3D Warehouse that Google maintains (thank you Google!) we are able to provide a 3D wiki of sorts that allows facilities and IT to work towards a reconciled design intent.  Once design intent is understood, the design specification process is quicker and far more simple.

You can see some examples of models we’ve built…

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Building the Cloud with Cisco Unified Computing System , EMC and VMware


Australian Curtin University of Technology is one of the first beta customers to sign up to a telecom provider ’s new private cloud-based service which utilises technology from Cisco, EMC and VMware and is also currently deploying an internal private cloud, based on the Cisco Unified Computing System  – An interesting journey to the cloud  presented by the Curtin University of Technology’s CIO, Peter Nikoletatos as described by Cisco Linda Horiuchi in her blog

if you want to know more about the deployment of this University at the forefront of the cloud computing adoption, listen to the roundtable organized with the systems integrator (Alphawest),the telecom provider (Optus Business) and the vendor partners (Cisco, EMC and VMware) in addition of Peter Nikoletatos


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Experience and benefits of Cisco Nexus and FCoE deployment at University of Arizona

Two of our favorite bloggers,  Kash Shaikh and Omar Sultan wrote several times on the emergence of the FCoE solution, and the benefits of the unified fabric approach

Today Kash Shaikh and Senior Director of IT Derek Masseth at University of Arizona talk about how customers are simplifying data centers with new FCoE Solution and how  consolidation, simplification and virtualization with unified fabric contribute to more business agility, significant cost reduction and investment protection in the existing customers infrastructures

 For those of you who want to know a little bit more about  Derek Masseth’s experience with FCoE and Nexus  deployment  here is the on-demand link for a 20 minutes presentation he made last September

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