Migrate data without mistakes


This article can also be found in the Premium Editorial Download "Storage magazine: The top email archiving strategies for storage managers."

Download it now to read this article plus other related content.

Practical considerations
Considerations for migration are threefold: whether the migration is between homogeneous arrays, heterogeneous arrays or among different tiers of storage. Migration between single tiers of storage--such as from one primary FC disk to another--can occur in homogeneous storage from a single vendor or in heterogeneous storage from multiple vendors.

Barry Thomas is network administrator at the Graves-Gilbert Clinic in Bowling Green, KY, which migrated to a Compellent SAN in January of this year. Thomas needed to use the most complicated approach, migrating between unlike storage devices.

Thomas chose to migrate the data from an EMC array, a Nexsan Technologies Inc. array and local servers to a Compellent SAN he had purchased. "We didn't do a lot of migrating before; we just way-overallocated storage to take care of that. It's expensive," he says. "The few times we had to do that we took the whole system down, moved from one storage solution to another and brought it back up."

The Graves-Gilbert Clinic had three EMC Clariion CX300 arrays, a Nexsan SATAboy and local storage on its servers, says Thomas. "We chose to give a temporary server the original volume and then give it the new Compellent volume. [We] then copied the data over from the old volume to the new volume using the Thin Import capability. If I gave the server a 100 gig volume

Requires Free Membership to View

that only had 80 gigs of data, then I only really consumed 80 gigs of volume space in the new array," he explains.

"We used scripting on one occasion; during the day, I presented a new volume to the server and used the script to basically shut down all the services, copy data from one volume to the next and [then] send me a message when it was done," says Thomas. "I then came in and changed the volume label and it was good to go."

Eric Nelson, director of information technology and CIO at St. Joseph Healthcare in Bangor, ME, used an appliance-based system to accomplish his data migration between heterogeneous devices. The hospital has 140 servers, eight virtual hosts and 94 virtual machines. It manages 14TB of data with a Sanrad V-Switch cluster, 28TB of data on a Hewlett-Packard (HP) Co. StorageWorks Enterprise Virtual Array (EVA) and 15TB on an EMC Symmetrix. To avoid vendor lock-in and redundant SANs at both of the hospital's sites, Nelson used a Sanrad V-Switch to migrate data from the EMC array to the HP StorageWorks EVA.

"Being that they were dissimilar SANs, I couldn't replicate between the two of them," says Nelson. "The only options vendors were giving me was to buy another one of their SANs and then they would set me up for replication. That's pretty expensive."

According to Nelson, "Sanrad was able to do asynchronous replication between different systems. We moved 13TB from the EMC Symmetrix to the HP EVA 8100. The migration was different depending on the application we used. We migrated the virtual machines with VMware tools. We had some issues with our file servers; for those migrations, we used backup and restore operations. At the same time, we were creating four different Microsoft clusters. We took those systems offline, backed up the data and then restored it to the new systems."


This was first published in June 2008

There are Comments. Add yours.

TIP: Want to include a code block in your comment? Use <pre> or <code> tags around the desired text. Ex: <code>insert code</code>

REGISTER or login:

Forgot Password?
By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy
Sort by: OldestNewest

Forgot Password?

No problem! Submit your e-mail address below. We'll send you an email containing your password.

Your password has been sent to: