AWS Storage Gateway, Руководство пользователя

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AWS Storage Gateway User Guide
Understanding Volume Status and Transitions
Status Meaning
Deleting The volume is currently being deleted. The Deleting status is transitional. No
action is required.
Irrecoverable An error occurred from which the volume cannot recover. For information on
what to do in this situation, see Troubleshooting Volume Issues (p. 331) .
Pass Through Data maintained locally is out of sync with data stored in AWS. Data written
to a volume while the volume is in Pass Through status remains in the cache
until the volume status is Bootstrapping . This data starts to upload to AWS
when Bootstrapping status begins.
The Pass Through status can occur for several reasons, listed following:
• The Pass Through status occurs if your gateway has run out of upload
buffer space. Your applications can continue to read from and write data
to your storage volumes while the volumes have the Pass Through status.
However, the gateway isn't writing any of your volume data to its upload
buffer or uploading any of this data to AWS.
The gateway continues to upload any data written to the volume before
the volume entered the Pass Through status. Any pending or scheduled
snapshots of a storage volume fail while the volume has the Pass Through
status. For information about what to do when your storage volume has
the Pass Through status because the upload buffer has been exceeded,
see Troubleshooting Volume Issues (p. 331) .
To return to ACTIVE status, a volume in Pass Through must complete the
Bootstrapping phase. During Bootstrapping , the volume re-establishes
synchronization with in AWS, so that it can resume the record (log) of
changes to the volume, and re-enable
CreateSnapshot
functionality.
During Bootstrapping , writes to the volume are recorded in upload buffer.
• The Pass Through status occurs when there is more than one storage
volume bootstrapping at once. Only one gateway storage volume can
bootstrap at a time. For example, suppose that you create two storage
volumes and choose to preserve existing data on both of them. In this
case, the second storage volume has the Pass Through status until
the first storage volume finishes bootstrapping. In this scenario, you
don't need to act. Each storage volume changes to the Available status
automatically when it is finished being created. You can read and write
to the storage volume while it has the Pass Through or Bootstrapping
status.
• Infrequently, the Pass Through status can indicate that a disk allocated
for upload buffer use has failed. For information about what action to take
in this scenario, see Troubleshooting Volume Issues (p. 331) .
• The Pass Through status can occur when a volume is in Active or
Bootstrapping state. In this case, the volume receives a write, but the
upload buffer has insufficient capacity to record (log) that write.
• The Pass Through status occurs when a volume is in any state and the
gateway is not shut down cleanly. This type of shutdown can happen
because the software crashed or the VM was powered off. In this case, a
volume in any state transitions to Pass Through status.
API Version 2013-06-30
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