Storage Configurations
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Chunk Size Support With ISB
All ISBs (i500, i1000, and i2000) support the 512 KB chunk size. Although you must have the
new v2.x switch hardware (ISS2000 and IXS2000) to use the 512 KB chunk size.
Adding an ISB to the File System
If you add an ISB (displays as an available storage element) to your file system, make sure you
match the chunk size of the new storage element to the chunk size of the existing storage group.
New storage elements are added with a default chunk size of 512 KB. You cannot mix chunk
sizes within a Storage Group. To change the chunk size of an ISB, you must remove the new
storage element from the file system and add the storage element again choosing the correct
chunk size.
Adding or Removing ISBs (Mirrored or RAID)
When permanently adding or removing ISBs from an ISIS Storage Group it is recommended to
do a full redistribution for all workspaces in the Storage Group. The full redistribution should be
done after the ISB add or remove is complete. Examples of permanent changes would be adding
or removing an engine to the storage stack.
The full redistribution makes sure all blocks in the Storage Group are optimally distributed based
on the new permanent configuration. Doing a full redistribution immediately after the permanent
adds or removes minimizes the chances of running into issues if a full redistribution is required
in the future. One potential issue would be the storage blades getting full during a full
redistribution and requiring the user to delete files to allow the redistribution to complete.
This recommendation does not apply to the case of removing and then replacing failed storage
blades. For other examples of symmetric and non-symmetric redistributions, see the
Avid ISIS
Performance and Redistribution Guide
on the Knowledge Base at
Moving Workspaces Between Storage Groups
You can move workspaces between Storage Groups that use the same chunk sizes. Workspaces
cannot be moved between Storage Groups of different chunk sizes (256 KB and 512 KB chunk
sizes),
A Tech Alert has been written describing the process for moving data from a 256 KB chunk size
workspace to a 512 KB chunk size workspace. Search the Avid Knowledge Base at
for
Avid ISIS v2.x Moving Workspaces using RichCopy
in the
Avid ISIS Tech Alerts.
