Case Study: I can see clearly now

Moorfields Eye Hospital is the oldest and largest specialist eye hospital in the world offering an internationally renowned ophthalmic service. Over half the ophthalmologists practising in the UK, and many more overseas, have received specialist training there. In partnership with the Institute of Ophthalmology it manages the largest ongoing ophthalmic research programme in the world, and was one of the country's first NHS Foundation Trusts.

Steve Gill, in charge of Moorfield's infrastructure support, says Moorfields has 65-70 Windows servers, lots of big machines, and lots of drives all running out of disk space: "We are storing thousands of electronic patient records, tens of thousands of scanned paper patient records, several hundred thousand images of eyes, millions of patient demographics and appointments, and millions of files on staff home drives."

He was forever getting requests for more capacity to yet another machine for a specific task which meant ordering more disks or upgrading the servers. Backup was another problem area with s many servers.

There had to be a different way of running his storage facilities, Gill said: "We were getting increasing demands for more capacity and so either had to begin replacing servers with larger servers or implementing a SAN. We wanted to make sure the overall cost per Terabyte was low as well as the ongoing cost to manage it. I was wary about getting sucked into a single supplier solution and having to buy more and more of their products."

Having requested supplier responses to questions Gill said: "We reviewed many solutions looking at NAS as well as SAN including EMC and HP SAN offerings. All the SAN proposals were for FC SANs until NCE suggested an iSCSI solution using our existing Ethernet LAN."

Although the SAN seemed a good idea fiber channel appeared very costly, restrictive and overly complicated.

Storage systems house NCE suggested a DataCore SANmelody/NexSAN IP SAN solution. Gill liked it: "I was attracted by the ability to use our existing IP network as fiber channel introduced an additional complexity. Following our research we felt that virtualization and iSCSI gave us the most options, and of course cost was critical. SANmelody fulfilled our requirements, and was flexible, cost-effective and scaleable."

Moorfields went ahead and implented the iSCSI SAN scheme. Gill describes the basic setup thus: "The SANmelody storage server is an HP ML370, the additional PCI slots allow us to expand as needed. The storage is a 13TB FC-attached Nexsan ATABeast and the Tape Library is a 22TB Qualstar SAIT. Both the Nexsan and Qualstar are only 4U - so provide large capacity on reduced rackspace."

"The SANmelody configuration manages 13TB of SATA disk using four RAID5 sets and 2 hot spares."

With SANmelody able to provide centrally managed storage accessible from the existing LAN it immediately allowed all servers on the LAN to be backed up. Requests for additional storage can be satisfied in minutes through a simple volume management interface.

Gill said “It provides almost unlimited storage but uses only what is needed”. Smaller 1U servers can now be purchased as there is no need to have the internal disk expansion previously planned for, which saves rack space and ongoing costs.

The solution has saved hours in ongoing administration, and it has enabled the move to a DR solution where all data is synchronously mirrored to another location. Gill describes the benefits he appreciates: "SANmelody meant minimal disruption as only an iSCSI driver was needed to add to the servers. The caching meant that we get good performance from our Gigabit Ethernet and with DataCore’s multi-path failover available on iSCSI we have a highly available low cost solution."

"Without future vendor lock-in it enables us to buy competitively as we grow. The instant deployment was very beneficial and it is so easy when we get a call from a department needing more space for the images to simply provide a virtual 2TB for them to use, and we can do it all centrally."

At the end of the day Steve Gill says: “It just works”.