Unlike other Micro Focus "Product Support" forums, this forum was created to encourage technical discussions whereby a variety of opinions and experiences can be explored and compared. This post is an attempt engage Community Members in such a discussion and determine whether other topics should be explored.
In recent years, there has been lots of controversy over whether or not RAID 5 is still an appropriate configuration. At issue is the long array rebuild time after a drive failure and the amount of data that must be read to recalculate parity. If an Unrecoverable Read Error (URE) occurs during the rebuild of the array, the rebuild cannot complete and all data in the array is lost. The larger the array, the greater the likelihood of encountering an URE.
As an example, if the specifications for the drives in the array state they have an Unrecoverable Read Error rate of one per 10E14 Bits Read, that would suggest there is better than a fifty percent chance that an URE will be encountered during the rebuild of a 12 TB array. Of course, the devil is in the details and the interpretation of the specs but would you trust your data to an array having these characteristics?
I'm not going to provide a lot of background at this time. A quick Google search will will provide you with many arguments both for and against. I hope, as this thread evolves, we can come to a consensus whether or not RAID 5 is still an appropriate configuration and, if so, under what conditions.
What are your RAID 5 experiences?
Are you concerned about the probably of encountering an URE during the rebuild of an array?