Product specifications

Managing Storage Groups
63
For information about what is shown in the Storage Managers panel, see “Storage Manager Column List” on
page 34
. Some columns are hidden by default (see “Showing and Hiding Columns” on page 24).
Storage Groups on ISIS | 7500
Storage Groups are created from bound Storage Managers. First, you bind Storage Managers to the system, then you
create one or more Storage Groups using the Storage Managers. A Storage Manager can belong to only one Storage
Group. After you create a Storage Group you can create Workspaces.
Storage Groups and Chunk Sizes
Storage Managers are combined to create Storage Groups in the ISIS file system. When you bind a Storage Manager
you must select either 512 KB (default) or 256 KB chunk sizes. Earlier Avid ISIS releases used 256 KB chunk sizes.
These bound Storage Managers must all be of the same chunk size when you configure your Storage Group.
n
Avid ISIS switch hardware shipped with v1.x (ISS1000 and IXS1000) does not support 512 KB chunk sizes. If you
have Avid ISIS v2.x software running on v1.x switches, you must select the 256 KB chunk size when adding Storage
Managers to the file system to create Storage Groups.
You cannot change the chunk size of an existing Storage Group. If you need to change the chunk size of a Storage
Group, you must delete it and create a new one with the desired chunk size, using Storage Managers that use that
chunk size. The chunk size selection is available only when binding the Storage Managers.
Storage Managers and Chunk Sizes
All Avid ISIS | 7500 ISBs contain two drives, and are identified by the total amount of storage in the ISB; for
example, an ISB with two 1 terabyte (TB) drives is called an i2000. The supported chunk size available on each ISB
type is listed below:
• 256 KB—i500 and i1000 only
• 512 KB—All (i500, i1000, i2000, i4000, i8000); Requires v2.x switch hardware (ISS2000 and IXS2000)
RAID-6 Workspace, Single ISB Failure
When there is a single ISB failure in an ISIS Workspace configured with RAID-6 protection, the Workspace
continues to function normally but at a lower bandwidth. For more information, see
“Mirrored Workspace, Single
ISB Failure” on page 64
.
After confirming the failure of an ISB, Avid highly recommends that you initiate the remove redistribution process
immediately. There are two benefits to doing this:
• Immediately upon initiation of the remove redistribution, all new writes to the Workspace have the full benefit
of RAID-6 protection (dual-parity protection).
• Upon completion of the remove redistribution process, existing data in the Workspace is once again fully
protected. Prior to completion, if another ISB were to fail, the Workspace would be in an unprotected state
(though no data would be lost).
RAID-6 Workspace, Dual ISB Failure
An “unprotected state” occurs if two ISBs fail in a RAID-6 Workspace. In an unprotected state with no additional
failures, read operations continue to function normally at a lower bandwidth.