Why is my Amazon EBS volume stuck in the optimizing state when I modify the volume?

Short description

When you modify an Amazon EBS volume, the volume goes through a sequence of states. These volume states include modifying, optimizing, and completed.

If you increase the size of the volume, then the new size is available for use immediately after the modification. However, if the volume is in the optimizing state, then the performance of the volume is in between the source and target configuration specifications. The performance of the volume is measured in terms of I/O operations per second and throughput.

The amount of time it takes to modify an EBS volume depends on the configuration changes that are applied. An EBS volume of size 1 TiB can take up to 6 hours to be modified. However, the same volume might take 24 hours or longer in certain situations. The time it takes for volumes to be modified doesn't always scale linearly. A larger volume might take less time, and a smaller volume might take more time.

Resolution

After a volume is modified, wait for at least 6 hours to modify the volume again. If the volume is still in the optimizing state, then wait until the volume completes the modification. If you need to modify the volume it's in the optimizing state, then use the following workaround solution:

1. Use an Amazon EBS snapshot to restore a new EBS volume of the desired configurations. You can use an existing snapshot or create a new snapshot.
2. Detach the current EBS volume that is in the optimizing state.
3. Attach the newly restored EBS volume to the instance, and use it thereafter.

Note: The new EBS volumes restored from snapshots must be initialized to achieve maximum performance.

Related information

Why isn't my EBS volume increase reflected in my OS or Disk Management?