A move to a two-layer datacentre infrastructure has provided major benefits to the University of Auckland.
Late last year the university went to RFP to upgrade its datacentre in Grafton Road. It chose Juniper Network’s 3-2-1 datacentre network architecture.
“As we increased server virtualisation, our legacy three-layer datacentre network was becoming a growing constraint,” says James Harper, strategy and design manager on the university’s information technology service department.
“Using Juniper’s EX Series switches with Virtual Chassis fabric technology, we were able to collapse multiple switching layers in our legacy datacentre down to a simplified two-layer infrastructure. As a result, the datacentre network has become much easier to manage, with few devices and few interactions.”
Collapsing switch layers simplifies the network by eliminating the aggregation layer – a primary source of complexity – resulting in lower operating costs, better manageability and fewer switch interactions, says Ian Quinn, country manager for Juniper.
“The performance and manageability of the rack-level switching layer is equally important, especially as server virtualisation becomes commonplace. In traditional client-server datacentres, 75 percent of ethernet traffic is north to south, between users and servers. In virtualised datacentres, however, up to 85 percent of the traffic is between servers and virtual machines at the access layer, or east to west.
“By combining multiple physical switches into a single logical device using our Virtual Chassis fabric technology, server to server traffic does not need to travel north-south across switch layers in order to move east to west, achieving much more efficient network performance.”
The Auckland University solution comprises Juniper EX8216 modular ethernet switches forming the network core, with the fixed-configuration EX4500 and EX4200 switches at the top of the rack layer providing 10GbE and 1GbE access ports.
When deployed in a Virtual Chassis configuration, interconnected EX4200 switches behave as a single logical device, sharing a common Junos operating system and configuration file. The EX4500s also support Virtual Chassis technology and can be combined with EX4200s in the same Virtual Chassis configuration, enabling the university to keep things simple as it increases the number of server and storage racks requiring 10GbE connectivity.
The University of Auckland previously operated its datacentre in a dual vendor environment: Cisco and Juniper. The datacentre is relatively new, having been built in 2009.
Harper wasn’t able to put a cost to the two-layer move. “It’s been a constant drip-feed of investment,” he says. “There’s been a noticeable improvement in terms of cost and utilisation on racks.
“We’re moving to a service provider/private cloud where we act as the service provider for the faculties. We’ve started to move to lights out where it becomes a lot easier. For example, we’re not having to call in network engineers to patch cables.”
Previously, each of the virtual servers was running 14 cables, totaling 250 metres in length. That has been reduced to just 5 metres per server.
Harper says the university looked at several reference sites and case studies in similar environments before making its decision.
“We haven’t cut staff numbers but we haven’t expanded at the rate we would have had to [with the previous technology],” he says. “Also, more than half of our students now connect using wireless on a daily basis. We couldn’t do that previously.”
The datacentre is critical to high-level research and engineering projects involving high-performance computing. One such application is gravitational microlensing.