SNW - Insurance company details its storage consolidation

06.04.2006
Nationwide Mutual Insurance Co. consolidated 14 distributed storage-area networks into four in two production data centers in only 90 days using only four full-time storage experts for the actual migration. The result: By simplifying its SAN architecture, Nationwide doubled the number of terabytes its administrator can manage.

Alan Grantham, a storage architect at Nationwide, in Columbus, Ohio, told users at Storage Networking World yesterday that the massive storage consolidation, which was completed a year ago, came off without a glitch because of one thing -- planning.

Grantham said he wasn't allowed to reveal the project's cost or discuss return on investment, but he spoke candidly about barring senior IT management from his data center during the project, calculating the risk involved with consolidating a storage infrastructure and the importance of testing every failure you ever had in the past on the new SAN before going live. The project also involved consolidating 102 Fibre Channel switches to 20 director-class switches from Cisco Systems Inc.

According to Grantham, there are three paths for going live on a new storage architecture: a live migration, a partial migration and an off-line migration.

Live migrations represent a very high risk to businesses because any operator error can create an outage, Grantham said.

A partial migration, which uses multipath software to disable one data path at a time in order to redirect data flow to the new SAN, requires a well-documented environment and is also very high risk because one error resulting in a disabled path creates an outage on a host.