- What is the best strategy to move databases from one brand of storage to another without stopping the production, keeping in mind the size of database?
- Once step 1 is completed, we will be doing some testing on an EMC box. So, how can we apply incremental backups from HDS to EMC using our network (data conversion and transfer between two different brand storage boxes)?
- Are there any data-related issues while moving/transferring data from HDS to EMC?
There are a variety of ways to do this, and each has its own pros and cons. In my opinion, the easiest and most mature solution is to use a host-based volume manager from the OS platform manufacturer Veritas Software to create a mirror of the data on one storage platform to the other. The good news about this solution is that it is transparent to the application and the platform at hand and keeps the data synchronized while providing the ability to increase the size of the logical volume on the fly, without any system or application downtime. A host-based volume manager can also provide you with the ability to mirror the data over long distances using a volume replication feature, which builds on the single host instance volume manager and adds a second host to the equation; you then mirror the information from the primary host to a secondary host. The storage on the mirror, whether local or remote, does not have to be from the same vendors, nor does it have to have the same characteristics or topology, it simply has to be of the same size storage pool so all of the data can be kept synchronized.
There are a bunch of other options, including a switch-based mirroring solution, like a Cisco MDS switch with their virtualization solution, but this may require you to take a scheduled outage and rebuild your database from a backup copy. Also, this is a more costly option than purchasing a host-based volume manager. Also, I would check with the team at Oracle, as I wonder if they have a solution to mirror the database using an internal tool. I would also suggest that you check with the supported matrix for any of these solutions to ensure that your full solution is on the supported matrix so you know that you won't have any support issues in the longer term.
This was first published in October 2005