Cisco has announced the next piece of its software-defined networking strategy: a long-distance interconnect designed to simplify workload mobility between data centres.
The “stretched fabric” release of its Application Centric Policy Controller (APIC) allows each of the leaf and spine switches that form a fabric to be located up to 30 km apart.
As the company's senior product marketing manager for data centre solutions Ravi Balakrishnan explains here, the aim is better integration of environments spread across multiple data centres.
In particular, Balakrishnan says, workloads and virtual machines (VMs) become portable not only between hosts in a single data centre, but also across the wide area links between data centres.
“The stretched ACI fabric behaves the same way as a regular ACI fabric, supporting full VMM integration. For example, one VMWare vCenter operates across the stretched ACI fabric sites. The ESXi hosts from both sites are managed by the same vCenter and Distributed Virtual Switch (DVS),” he writes.
The distance a fabric can be stretched depends on the optical transceivers between the data centres, and Cisco's design overview notes that the stretched fabric also requires dark fibre links.
The stretched fabric also simplifies the overall infrastructure, Balakrishnan writes, by removing the need for all leaf switches to be connected to all spines.
Instead, transit leaf switches provide the point of connectivity between sites, and “There are no special requirements and no additional configurations required for transit leaf switches”. ®