A. The command

vssadmin list shadowstorage

gives information for each volume on a system and details the volume used for VSS snapshot storage, the amount of space being used by snapshots, the amount allocated for snapshots, and the maximum space that could be used.

C:\>vssadmin list shadowstorage
vssadmin 1.1 - Volume Shadow Copy Service administrative command-line
 tool
(C) Copyright 2001-2005 Microsoft Corp.

Shadow Copy Storage association
For volume: (C:)\\?\Volume\{a488ed41-38e8-11de-abc2-806e6f6e6963\}Shadow Copy
Storage volume: (C:)\\?Volume\{a488ed41-38e8-11de-abc2-806e6f6e69
63\}Used Shadow Copy Storage space: 5.547 MB (0%)
Allocated Shadow Copy Storage space: 1.5 GB (3%)
Maximum Shadow Copy Storage space: UNBOUNDED (100%)

As you can see, in this example only 5.5MB of space is being used by the snapshot, and there's no maximum to the amount of disk space usable by shadow copies.

Related Reading:

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