Two-Way Sync Conflict Handling

Overview

The sync engine supports two‑way synchronisation, allowing files and folders to stay aligned between two connected systems.

When the same item is updated on both systems between sync runs, a conflict occurs. The sync engine does not automatically merge these changes, instead, it follows a defined rule to decide which system “wins.”

This guide explains:

• How to configure conflict resolution settings
• What each setting does

How Two‑Way Sync Works

During each sync cycle, the platform performs the following steps when a change is detected:

1. Fetches changes from System A (source) and applies them to System B

   or

2. Fetches changes from System B (destination) and applies them back to System A

Important Notes

• The sync engine detects events only, such as:
  • Add
  • Update
  • Delete
  • Move
• The sync engine does NOT:
  • Compare file contents
  • Track versions across systems
  • Analyse what changed
  • Merge edits

What Is a Conflict?

A conflict occurs when the same file or folder is modified on both systems before the next sync is run.

Syncly does not evaluate which version is “better” it relies entirely on your configured conflict resolution setting.

Default Behaviour

By default the system is set to:

• The latest update wins

This means:

• Latest updates will overwrite other updates if both changed

Configuring Conflict Resolution

You can configure conflict behaviour at:

Admin → Workflow → Two‑Way Sync Settings

This setting defines the default conflict behaviour for new workflows. This is a universal system setting applied to all two-way sync workflows.

Available Settings

You can choose one of the following:

1. Source Wins on Conflict
2. Destination Wins on Conflict
3. Latest Timestamp Wins on Conflict

Conflict Resolution Settings Explained

1. Source Wins on Conflict

Behaviour:

• The source system is treated as the source of truth
• If both systems change the same item:
  • Source version overwrites destination

What happens to the losing changes:

• Destination changes are not lost
• They are saved as a previous version
• A new version is created using the source content

Use this when:

• One system must always be authoritative
• Example: Internal document repository controlling external copies

2. Destination Wins on Conflict

Behaviour:

• The destination system becomes the source of truth
• If both systems change the same item:
  • Destination version overwrites source

What happens to the losing changes:

• Source changes are saved as a previous version
• A new version is created using destination content

Use this when:

• The destination system is business-critical
• Example: HighQ or client-facing collaboration platform

3. Latest Timestamp Wins on Conflict

Behaviour:

• Syncly compares modification timestamps
• The most recently updated file wins

What happens to the losing changes:

• The overwritten version is saved as a previous version
• A new version is created with the latest update

Use this when:

• No single system is authoritative
• Recency is the best indicator of correctness

IMPORTANT NOTES: 

• If you select the option "Latest copy only" previous versions are removed and updates from the losing system will be lost. Leave this option deselected to retain all versions.
• Some systems may only use time stamp at minute level and not seconds. If one of the systems has seconds and the other system does not, the latest time including seconds will be deemed to win.
• Changing the default will update existing syncs to use the new behaviour

What Happens During a Conflict

When a conflict is detected:

1. Syncly identifies that both systems changed the same item
2. Applies the configured resolution rule
3. Preserves the losing version as a previous version
4. Creates a conflict event and if notifications are enabled, will send an email notification to all recipients

User Visibility

• A conflict is logged
• Optional alerts can be triggered
• A conflict icon appears in the workflow with a status of "Review".
  • Once reviewed, click review to update the status to "Reviewed"
  • If you have any conflicts in Review state on a workflow, no further notifications for additional conflicts will be sent. 

Important Limitations

To set correct expectations:

• Syncly does not merge documents
• Syncly does not analyse differences
• Syncly does not determine correctness of changes

It only decides which system wins based on your configuration.

Best Practices

• Choose Source Wins when one system must always control data
• Choose Destination Wins when external or client systems are primary
• Choose Latest Timestamp when collaboration is equal
• Leave 'Latest copy only' deselected

Summary

Conflict handling is designed to be:

• Predictable – clear rules determine outcomes
• Transparent – conflicts are logged and visible
• Configurable – you decide which system wins

By selecting the appropriate conflict resolution strategy, you ensure your synchronisation behaves exactly as your business requires.