Taking a snapshot - this is where any backup begins. Until we know how to flush all buffers to disk and bring data files to a consistent state, we do not make backups, but copy files with unpredictable contents inside. Understanding the importance of snapshots, all vendors try to give us, if not a completely finished function (like the Time Mashine in MacOS), then at least a set of knobs that can be pulled (like the dm-snap module in the Linux kernel).
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PS C:\Windows\system32> diskshadow
Microsoft DiskShadow version 1.0
Copyright (C) 2013 Microsoft Corporation
On computer: VEEAM, 17.05.2021 19:18:44
DISKSHADOW> add volume c: #
DISKSHADOW> create #
Alias VSS_SHADOW_1 for shadow ID {a1eef71e-247e-4580-99bc-ee62c42221d6} set as environment variable.
Alias VSS_SHADOW_SET for shadow set ID {cc9fab4d-3e7d-44a5-9a4d-0df11dd7219c} set as environment variable.
Querying all shadow copies with the shadow copy set ID {cc9fab4d-3e7d-44a5-9a4d-0df11dd7219c}
* Shadow copy ID = {a1eef71e-247e-4580-99bc-ee62c42221d6} %VSS_SHADOW_1%
- Shadow copy set: {cc9fab4d-3e7d-44a5-9a4d-0df11dd7219c} %VSS_SHADOW_SET%
- Original count of shadow copies = 1
- Original volume name: \\?\Volume{7fd0c79d-0000-0000-0000-602200000000}\ [C:\]
- Creation time: 17.05.2021 19:19:45
- Shadow copy device name: \\?\GLOBALROOT\Device\HarddiskVolumeShadowCopy2
- Originating machine: veeam.university.veeam.local
- Service machine: veeam.university.veeam.local
- Not exposed
- Provider ID: {b5946137-7b9f-4925-af80-51abd60b20d5}
- Attributes: Auto_Release Differential
Number of shadow copies listed: 1
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DISKSHADOW> expose {a1eef71e-247e-4580-99bc-ee62c42221d6} Z:
The shadow copy is a non-persistent shadow copy. Only persistent shadow copies can be exposed.
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DISKSHADOW> delete shadows all # ID
Deleting shadow copy {a1eef71e-247e-4580-99bc-ee62c42221d6} on volume \\?\Volume{7fd0c79d-0000-0000-0000-602200000000}\ from provider {b5946137-7b9f-4925-af80-51abd60b20d5} [Attributes: 0x00420000]...
Number of shadow copies deleted: 1
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DISKSHADOW> add volume C:
DISKSHADOW> set context persistent #
DISKSHADOW> create
Alias VSS_SHADOW_1 for shadow ID {346d896b-8722-4c01-bf01-0f38b9abe20a} set as environment variable.
Alias VSS_SHADOW_SET for shadow set ID {785983be-e09d-4d2a-b8b7-a4f722899896} set as environment variable.
Querying all shadow copies with the shadow copy set ID {785983be-e09d-4d2a-b8b7-a4f722899896}
* Shadow copy ID = {346d896b-8722-4c01-bf01-0f38b9abe20a} %VSS_SHADOW_1%
- Shadow copy set: {785983be-e09d-4d2a-b8b7-a4f722899896} %VSS_SHADOW_SET%
- Original count of shadow copies = 1
- Original volume name: \\?\Volume{7fd0c79d-0000-0000-0000-602200000000}\ [C:\]
- Creation time: 17.05.2021 19:38:45
- Shadow copy device name: \\?\GLOBALROOT\Device\HarddiskVolumeShadowCopy3
- Originating machine: veeam.university.veeam.local
- Service machine: veeam.university.veeam.local
- Not exposed
- Provider ID: {b5946137-7b9f-4925-af80-51abd60b20d5}
- Attributes: No_Auto_Release Persistent Differential
Number of shadow copies listed: 1
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