2020/07/09 - Amazon Elastic Block Store - 3 new api methods
Changes This release introduces the following set of actions for the EBS direct APIs: 1. StartSnapshot, which creates a new Amazon EBS snapshot. 2. PutSnapshotBlock, which writes a block of data to a snapshot. 3. CompleteSnapshot, which seals and completes a snapshot after blocks of data have been written to it.
Writes a block of data to a block in the snapshot. If the specified block contains data, the existing data is overwritten. The target snapshot must be in the pending state.
Data written to a snapshot must be aligned with 512-byte sectors.
See also: AWS API Documentation
Request Syntax
client.put_snapshot_block(
SnapshotId='string',
BlockIndex=123,
BlockData=b'bytes'|file,
DataLength=123,
Progress=123,
Checksum='string',
ChecksumAlgorithm='SHA256'
)
string
[REQUIRED]
The ID of the snapshot.
integer
[REQUIRED]
The block index of the block in which to write the data. A block index is the offset position of a block within a snapshot, and it is used to identify the block. To identify the logical offset of the data in the logical volume, multiply the block index with the block size (Block index * 512 bytes).
bytes or seekable file-like object
[REQUIRED]
The data to write to the block.
The block data is not signed as part of the Signature Version 4 signing process. As a result, you must generate and provide a Base64-encoded SHA256 checksum for the block data using the x-amz-Checksum header. Also, you must specify the checksum algorithm using the x-amz-Checksum-Algorithm header. The checksum that you provide is part of the Signature Version 4 signing process. It is validated against a checksum generated by Amazon EBS to ensure the validity and authenticity of the data. If the checksums do not correspond, the request fails. For more information, see Using checksums with the EBS direct APIs in the Amazon Elastic Compute Cloud User Guide .
integer
[REQUIRED]
The size of the data to write to the block, in bytes. Currently, the only supported size is 524288 .
Valid values: 524288
integer
The progress of the write process, as a percentage.
string
[REQUIRED]
A Base64-encoded SHA256 checksum of the data. Only SHA256 checksums are supported.
string
[REQUIRED]
The algorithm used to generate the checksum. Currently, the only supported algorithm is SHA256 .
dict
Response Syntax
{
'Checksum': 'string',
'ChecksumAlgorithm': 'SHA256'
}
Response Structure
(dict) --
Checksum (string) --
The SHA256 checksum generated for the block data by Amazon EBS.
ChecksumAlgorithm (string) --
The algorithm used by Amazon EBS to generate the checksum.
Creates a new Amazon EBS snapshot. The new snapshot enters the pending state after the request completes.
After creating the snapshot, use PutSnapshotBlock to write blocks of data to the snapshot.
See also: AWS API Documentation
Request Syntax
client.start_snapshot(
VolumeSize=123,
ParentSnapshotId='string',
Tags=[
{
'Key': 'string',
'Value': 'string'
},
],
Description='string',
ClientToken='string',
Encrypted=True|False,
KmsKeyArn='string',
Timeout=123
)
integer
[REQUIRED]
The size of the volume, in GiB. The maximum size is 16384 GiB (16 TiB).
string
The ID of the parent snapshot. If there is no parent snapshot, or if you are creating the first snapshot for an on-premises volume, omit this parameter.
If your account is enabled for encryption by default, you cannot use an unencrypted snapshot as a parent snapshot. You must first create an encrypted copy of the parent snapshot using CopySnapshot.
list
The tags to apply to the snapshot.
(dict) --
Describes a tag.
Key (string) --
The key of the tag.
Value (string) --
The value of the tag.
string
A description for the snapshot.
string
A unique, case-sensitive identifier that you provide to ensure the idempotency of the request. Idempotency ensures that an API request completes only once. With an idempotent request, if the original request completes successfully. The subsequent retries with the same client token return the result from the original successful request and they have no additional effect.
If you do not specify a client token, one is automatically generated by the AWS SDK.
For more information, see Idempotency for StartSnapshot API in the Amazon Elastic Compute Cloud User Guide .
This field is autopopulated if not provided.
boolean
Indicates whether to encrypt the snapshot. To create an encrypted snapshot, specify true . To create an unencrypted snapshot, omit this parameter.
If you specify a value for ParentSnapshotId , omit this parameter.
If you specify true , the snapshot is encrypted using the CMK specified using the KmsKeyArn parameter. If no value is specified for KmsKeyArn , the default CMK for your account is used. If no default CMK has been specified for your account, the AWS managed CMK is used. To set a default CMK for your account, use ModifyEbsDefaultKmsKeyId.
If your account is enabled for encryption by default, you cannot set this parameter to false . In this case, you can omit this parameter.
For more information, see Using encryption in the Amazon Elastic Compute Cloud User Guide .
string
The Amazon Resource Name (ARN) of the AWS Key Management Service (AWS KMS) customer master key (CMK) to be used to encrypt the snapshot. If you do not specify a CMK, the default AWS managed CMK is used.
If you specify a ParentSnapshotId , omit this parameter; the snapshot will be encrypted using the same CMK that was used to encrypt the parent snapshot.
If Encrypted is set to true , you must specify a CMK ARN.
integer
The amount of time (in minutes) after which the snapshot is automatically cancelled if:
No blocks are written to the snapshot.
The snapshot is not completed after writing the last block of data.
If no value is specified, the timeout defaults to 60 minutes.
dict
Response Syntax
{
'Description': 'string',
'SnapshotId': 'string',
'OwnerId': 'string',
'Status': 'completed'|'pending'|'error',
'StartTime': datetime(2015, 1, 1),
'VolumeSize': 123,
'BlockSize': 123,
'Tags': [
{
'Key': 'string',
'Value': 'string'
},
],
'ParentSnapshotId': 'string',
'KmsKeyArn': 'string'
}
Response Structure
(dict) --
Description (string) --
The description of the snapshot.
SnapshotId (string) --
The ID of the snapshot.
OwnerId (string) --
The AWS account ID of the snapshot owner.
Status (string) --
The status of the snapshot.
StartTime (datetime) --
The timestamp when the snapshot was created.
VolumeSize (integer) --
The size of the volume, in GiB.
BlockSize (integer) --
The size of the blocks in the snapshot, in bytes.
Tags (list) --
The tags applied to the snapshot. You can specify up to 50 tags per snapshot. For more information, see Tagging your Amazon EC2 resources in the Amazon Elastic Compute Cloud User Guide .
(dict) --
Describes a tag.
Key (string) --
The key of the tag.
Value (string) --
The value of the tag.
ParentSnapshotId (string) --
The ID of the parent snapshot.
KmsKeyArn (string) --
The Amazon Resource Name (ARN) of the AWS Key Management Service (AWS KMS) customer master key (CMK) used to encrypt the snapshot.
Seals and completes the snapshot after all of the required blocks of data have been written to it. Completing the snapshot changes the status to completed . You cannot write new blocks to a snapshot after it has been completed.
See also: AWS API Documentation
Request Syntax
client.complete_snapshot(
SnapshotId='string',
ChangedBlocksCount=123,
Checksum='string',
ChecksumAlgorithm='SHA256',
ChecksumAggregationMethod='LINEAR'
)
string
[REQUIRED]
The ID of the snapshot.
integer
[REQUIRED]
The number of blocks that were written to the snapshot.
string
An aggregated Base-64 SHA256 checksum based on the checksums of each written block.
To generate the aggregated checksum using the linear aggregation method, arrange the checksums for each written block in ascending order of their block index, concatenate them to form a single string, and then generate the checksum on the entire string using the SHA256 algorithm.
string
The algorithm used to generate the checksum. Currently, the only supported algorithm is SHA256 .
string
The aggregation method used to generate the checksum. Currently, the only supported aggregation method is LINEAR .
dict
Response Syntax
{
'Status': 'completed'|'pending'|'error'
}
Response Structure
(dict) --
Status (string) --
The status of the snapshot.