When working with VMware's snapshot mechanism, it's crucial to understand the parent-child relationship between snapshots. Consider this hierarchical structure:

Base
├── SnapshotA
    ├── SnapshotB
        └── SnapshotC

When you delete SnapshotB in this chain, VMware automatically promotes its child (SnapshotC) to become a direct child of SnapshotA. The virtual machine continues to reference SnapshotC, maintaining consistency.

Example CLI command to delete a snapshot:

vim-cmd vmsvc/snapshot.remove [VM_ID] [SNAPSHOT_ID]

The documentation correctly states that deleting a snapshot commits its data to the parent. In your case:

• All changes made in SnapshotB (installed software, modified files) get merged into SnapshotA
• The delta disk files (*-delta.vmdk) are consolidated
• The snapshot metadata (.vmsd file) is updated

Here's what actually happens at the filesystem level when deleting SnapshotB:

1. VMware creates temporary consolidated files
2. Changes from SnapshotB's delta disk merge into SnapshotA
3. The snapshot chain rewrites to bypass SnapshotB

PowerShell snippet to monitor snapshot consolidation:

Get-VM | Where {$_.ExtensionData.Snapshot -ne $null} | 
Select Name, @{N="SnapshotCount";E={$_.ExtensionData.Snapshot.Count}}

Deleting snapshots isn't instantaneous. The operation:

• Requires sufficient storage for temporary consolidation files
• Causes increased I/O during the merge process
• May temporarily impact VM performance

Example Python script to calculate required space:

import os
def estimate_consolidation_space(vmdk_path):
    delta_files = [f for f in os.listdir(vmdk_path) if f.endswith('-delta.vmdk')]
    total_size = sum(os.path.getsize(os.path.join(vmdk_path, f)) for f in delta_files)
    return total_size * 1.2  # Add 20% buffer

When working with snapshot chains:

• Always document your snapshot tree before deletion
• Monitor storage space before consolidation operations
• Consider taking new snapshots after major changes rather than keeping long chains
• Use the vSphere API for programmatic control in automation scenarios

Example API call to get snapshot hierarchy:

GET https://{vcenter}/rest/vcenter/vm/{vm}/snapshot

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When working with VMware snapshots, it's crucial to understand the parent-child relationship in the snapshot chain. Consider this typical hierarchy:

Base Disk
├── SnapshotA.vmdk
    ├── SnapshotB.vmdk
        └── SnapshotC.vmdk

When you delete SnapshotB in this chain, VMware handles the operation in a specific way:

1. The contents of SnapshotB are committed (merged) into its parent (SnapshotA)
2. SnapshotC becomes a direct child of SnapshotA
3. The snapshot chain is automatically reorganized to maintain data integrity

Here's what the chain looks like post-deletion:

Base Disk
├── SnapshotA.vmdk
    └── SnapshotC.vmdk

The VMware documentation correctly states that deleting a snapshot commits its data to the parent. This means:

• Any software installed or files added during SnapshotB's lifetime
• All disk changes captured in SnapshotB's delta disk
• Memory state if it was a snapshot with memory

All these elements become part of SnapshotA when you delete SnapshotB. The virtual machine's current state remains unchanged.

Here's how you might manage snapshots programmatically using VMware PowerCLI:

# Connect to vCenter
Connect-VIServer -Server vcenter.example.com

# Get the VM and its snapshots
$vm = Get-VM -Name "TestVM"
$snapshots = Get-Snapshot -VM $vm

# Display snapshot tree
$snapshots | ForEach-Object {
    Write-Host "Snapshot: $($_.Name) (Created: $($_.Created))"
    if ($_.ParentSnapshot) {
        Write-Host "tParent: $($_.ParentSnapshot.Name)"
    }
}

# Delete SnapshotB safely
$snapshotB = Get-Snapshot -VM $vm -Name "SnapshotB"
Remove-Snapshot -Snapshot $snapshotB -Confirm:$false

# Verify new hierarchy
Get-Snapshot -VM $vm | Select-Object Name,ParentSnapshotName

Deleting snapshots, especially in long chains, can impact performance:

Operation	Impact
Deleting leaf snapshot	Minimal impact
Deleting middle snapshot	Moderate impact
Deleting with large delta disks	Significant impact

• Always document your snapshot hierarchy before deletion
• Schedule snapshot deletions during maintenance windows
• Monitor storage performance during commit operations
• Consider using VMware's Storage vMotion for large snapshots