The benefits of SAN

gallery

A wide range of organisations now use a SAN, and not all of them major multinationals. Here we talk to a couple of senior IT professionals to find just what they've gained from switching to a SAN model, and where they hope the technology will evolve.

Zafar Chaudry, director of information management and technology with Liverpool Women's NHS Foundation Trust

Liverpool Women's is one of the UK's premier hospitals in the provision of healthcare to women and babies, specialising in the fields of maternity, neonatology, gynaecology, reproductive medicine, breast surgery and genetics.

Data storage has not, however, been a historic strong point: "Until quite recently, there was no storage strategy in place here at all" says Chaudry. "When I started here in 2005, I had the job of looking at the server and storage infrastructure, as it did not seem to be delivering."

He says he found an old HP server, some storage arrays and standalone desktops all over the place. "There was nothing like a data centre, just 500GB of data spread everywhere," he says. "Only around 50GB was backed up."

He decided to look for a platform to put all data on so that it could be managed centrally.

"We looked at a straightforward direct-attached storage model, but it lacked the features we were looking for," he recalls. "Then we looked at a system based around networked arrays, both at iSCSI and Fibre Channel options. We considered a number of different vendors - Network Appliance, HP, EMC. In the end we went with EMC and a Fibre Channel storage area network. We had a new network already with Fibre Channel all over the place, so it made sense."

A Clariion EX500 is now mirrored asynchronously using MirrorView to another server 300 metres away. "Some data is now stored so it's near at hand, while the rest is archived," says Chaudry. "You could call this an information lifecycle management strategy, of sorts. Data is mirrored every 30 minutes, and a full snapshot of all data made every four hours."

He says the new system has proved easy to manage through a portal that EMC provided: "I dare say all the major vendors provide something similar," he says. "It's configured so they can send us a warning by email if anything isn't working."

With any SAN, says Chaudry, you need training: "One of the three guys who manage it had to be sent off to be trained."

He says he now knows where all data resides, which he didn't before. "We have a proper data centre, not just space under people's desks," he says. "We have capacity for 3Tb, which is about half full, so you can see the amount of data we hold has grown. Scalability has not so far been an issue. I feel that we're future proofed for at least five years. We've got a support contract for those five years, so we can stay protected. The most we can lose is 30 minutes of data.

He says the new et up has been reliable, by and large. "The only thing that's failed has been a disk on the second server where the data is mirrored, not the main one in daily use. Maybe it's like a car where the more you drive it the more reliable it becomes."

Backing up data used to take 22 or 23 hours, he says, now a six hour cycle.

"We did spend a fair amount of money on the system - about £400,000 in all, which isn't too bad in the scheme of things," he says. "That's for a system that supports 1,500 users. To give an idea of the size of this organisation, we deliver about 8,000 babies a year, and turn over £75 million."

Email to a friend

Print this page