The water company provides 152 million litres of water a day to 650,000 people in domestic and commercial properties and runs billing, payroll GIS and lab systems on 20 Windows and two Solaris servers at its Redhill, Surrey, headquarters. The servers were using direct-attached storage and data was being backed up to a Quantum DLT tape drive using Computer Associates' ArcServe backup software and homegrown Unix tools.
"The IT department and the business recognised that backing up to tape, while a very efficient method of storing data, was risky and time-consuming when it came to recovery," Cock said. "We really didn't know what our recovery time would be. The best estimate was about one week, in which time we would have had to source servers and software and re-install the data."
Following a procurement process that culminated in a shortlist of Dell/EMC Fibre Channel SAN and NetApp, the NetApp unified file/block-level access products won out on ease of implementation and use. The water company chose to go with a pair of NetApp filers – a FAS3020C at the live site and a FAS270 at a DR site in Sevenoaks, both of 4.5 TB capacity. About 40% of capacity is allocated to database and Microsoft Exchange files via block-level access, 40% sharing Windows files using CIFS and 20% to applications on Solaris via NFS.
The company now only archives to tape – on an HP StorageWorks Ultrium 960 – but all existing data was put onto the filers during the migration and primary backup is achieved using NetApp SnapShot and SnapMirror to replicate to the DR site.
The benefits for Sutton & East Surrey Water have been that it has slashed potential recovery times in case of a major loss of data. According to Cock, this has probably made the difference between the business failing or not if disaster should strike. "We have not got any concrete ROI figures apart from the knowledge that should we have suffered a disaster at our head office site the business would not have been able to continue," he said. "So the ROI, in effect, was the value of the business."
He added, "When the auditors came and tested our disaster recovery, they said it was the best demo they'd ever seen. Of the 41 applications we brought up, we only had a problem with three of them."
The new setup has also saved staff time spent pulling back copies of user files when they lose or accidentally delete them because they are now available to users almost instantaneously from the mirror site.
"It has also brought us far greater ease of recovery of data," Cock said. "Every user has access to the backups and can recover their own data, rather than needing to wait two to four hours to get it back from tapes. Also, some of the tech team used to spend hours optimising spindles to get the most out of our storage. Now it's done in seconds."
NetApp won out on the grounds of ease of implementation and maintenance on the basis of its filers' ability to access data at both file and block level, said Cock. "The main reason for choosing NetApp over EMC/Dell was simplicity," he said. "Most suppliers at the time drew a distinction between NAS and SAN. If you wanted a Windows file server you were pointed in the direction of NAS and if your company was big, then you were told you would need a SAN. That was very much the direction that EMC/Dell was coming from."