One-way sync copies changes from a source location to a destination and never sends changes back. Two-way (bidirectional) sync keeps two locations matching by propagating changes in both directions, so an edit made on either side appears on the other.
Why it matters
The choice affects safety and complexity. One-way sync is simple and predictable, and suits mirroring and publishing, but an accidental deletion at the source is copied to the destination, so it is not a backup. Two-way sync suits files, calendars and contacts used on several devices, but it can produce conflicts when the same item changes in both places before syncing. Systems resolve this with rules such as last write wins, keeping both copies, or asking the user.
Example
Two devices edit notes.txt while offline:
Laptop: "Buy milk" -> "Buy milk and eggs" (10:02)
Phone: "Buy milk" -> "Buy oat milk" (10:05)With last-write-wins, the phone's version replaces the laptop's and the eggs edit is lost. Some tools instead save notes (conflicted copy).txt so nothing disappears.
Common mistakes
- Using one-way mirroring as the only backup, so deletions propagate.
- Syncing a live database file with a file sync tool and corrupting it.
- Ignoring conflict warnings.
Related
Get notified when this term updates
Plus occasional practical tips on uptime and monitoring, nothing else. Unsubscribe anytime.
यह पेज सामान्य जानकारी है, जिसे हमारी संपादकीय टीम ने लिखा है और दस्तावेज़ीकरण बदलने पर अपडेट किया जाता है। सर्वर और प्रदाता अलग-अलग होते हैं, इसलिए बदलाव पहले सुरक्षित तरीके से जाँचें। देखें: संपादकीय नीति और अस्वीकरण.