Tomar una instantánea: aquí es donde comienza cualquier copia de seguridad. Hasta que sepamos cómo vaciar todos los búferes del disco y llevar los archivos de datos a un estado coherente, no hacemos copias de seguridad, sino que copiamos archivos con contenido impredecible en su interior. Al comprender la importancia de las instantáneas, todos los proveedores intentan brindarnos, si no una función completamente terminada (como Time Mashine en MacOS), al menos un conjunto de perillas que se pueden extraer (como el módulo dm-snap en el kernel de Linux ).
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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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