At first glance, using rsync for VMware backups seems elegant:

# Basic rsync example for VM backup
vim-cmd vmsvc/snapshot.create [vmid] "Backup Snapshot" "Pre-rsync backup" 1 1
rsync -avz --progress /vmfs/volumes/datastore1/VMNAME/ backup-server:/vm-backups/
vim-cmd vmsvc/snapshot.remove [vmid] [snapshot-id]

This approach works for small-scale environments, but breaks down in enterprise scenarios for several technical reasons.

1. Snapshot Chain Management:
VMware snapshots aren't designed for frequent backup operations. Each snapshot creates delta disks that impact performance. Professional backup solutions handle this through:

# Enterprise backup tools typically:
1. Create temporary snapshot
2. Use Changed Block Tracking (CBT)
3. Immediately commit snapshot
4. Transfer only changed blocks

2. Application Consistency:
While you can use the quiesce flag (vim-cmd vmsvc/snapshot.create [vmid] "" 1 1), this only works for VMware Tools-aware applications. Enterprise backup solutions integrate with:

• SQL Server VSS writers
• Exchange database awareness
• Active Directory transaction logs

Rsync transfers entire files when inodes change, while professional solutions leverage VMware's Changed Block Tracking (CBT):

# Sample CBT query (requires proper authentication)
vim-cmd vmsvc/get.cbt [vmid]

Enterprise backup products can achieve 90%+ reduction in backup size through CBT-aware transfers.

An rsync-based solution lacks:

For small, non-critical Linux VMs with these characteristics:

# Example rsync backup script with basic safety checks
#!/bin/bash
VMID=$(vim-cmd vmsvc/getallvms | grep "MyVM" | awk '{print $1}')
SNAP_ID=$(vim-cmd vmsvc/snapshot.create $VMID "Backup $(date +%Y-%m-%d)" "" 1 1 | grep -oP '(?<=Snapshot).*?(?=created)')

rsync --rsync-path="sudo rsync" \
      -avz --del \
      --exclude='*.log' \
      --exclude='*.tmp' \
      /vmfs/volumes/datastore1/VMNAME/ \
      backupuser@backupserver:/vm-backups/

vim-cmd vmsvc/snapshot.remove $VMID $SNAP_ID

Even in these cases, consider adding at least:

• Email notifications on failure
• Log rotation for the script output
• Pre-backup disk space checks

While your proposed rsync method works technically, enterprise environments face challenges that raw rsync can't address:

# Example rsync command you might use:
rsync -azP --delete /vmfs/volumes/datastore1/VM_NAME/ backup-server:/backups/VM_NAME/

1. Crash-Consistent vs Application-Consistent Backups
Snapshot quiescing only ensures filesystem consistency, not application consistency. Enterprise backup solutions integrate with VSS (Windows) or fs-freeze (Linux) for true application-consistent backups.

# Example of proper quiescing sequence:
vim-cmd vmsvc/snapshot.create [vmid] "Backup Snapshot" 1 1 0
# ...rsync operations...
vim-cmd vmsvc/snapshot.remove [vmid] [snapshotid]

2. Storage System Complexity
Modern VM environments use:

• VMFS-6/NFSv4.1 datastores
• vSAN storage policies
• RDMs and VVOLs

For small-scale, non-critical Linux VMs with:

#!/bin/bash
# Simple backup script example
VMID=$(vim-cmd vmsvc/getallvms | grep "MyVM" | awk '{print $1}')
SNAPID=$(vim-cmd vmsvc/snapshot.create $VMID "Backup $(date +%F)" \
  "Backup" 1 1 0 | awk '{print $NF}')
  
rsync -azP --delete /vmfs/volumes/datastore1/MyVM/ backup01:/backups/MyVM/

vim-cmd vmsvc/snapshot.remove $VMID $SNAPID

For those wanting simple solutions:

• VMware's native vSphere Data Protection
• Open-source Bacula with VMware plugin
• Restic with vSphere API integration