Data management tools
Data migration options
By Brett Cooper
The easiest option would be to schedule maintenance (telling all users and associated applications that the main database will be going down for a period of time), perform a full backup to tape of the database and other files that are kept on the local storage, then move to the new storage environment and do a restore, testing before putting the system back into production.
The next option is a bit more complex and does not leave you with a backup copy of the data (I would strongly suggest taking a backup before trying this or any other solution). Take a scheduled maintenance period and install the SAN. Copy the database in its entirety and all associated files to the SAN, reconfigure the database and you are on your way. Also, most databases will allow you to log writes to another location to protect against failures during operations. You can setup the journaling option of your database to do this as well.
Finally, you can use the AIX Logical Volume Manager (LVM) to create a mirror of the database storage from your local storage to the SAN storage. This provides a great advantage as the mirror is a perfect copy of the information within the environment.
If you want to setup a larger environment, you can always setup a remote mirror to another host that has the SAN storage behind it using Veritas Volume Replicator or other remote mirroring solution. This will cost you some budget dollars and will still require a scheduled maintenance period to install the software and configure the environment.
I would strongly suggest testing in a lab prior to the move to the SAN and documenting the procedure you select. In addition, I would suggest working with the vendor of the SAN equipment to insure that you have the right level/latest device drivers and firmware for each part in the SAN: HBA, switch and storage device.
28 Nov 2005