Four ways to sync your Obsidian vault across devices

Conflict markers land directly inside the note body

We created one bare repository and cloned it twice, standing in for two devices. With both "offline", each appended a different line to the same note and committed, then pushed one after the other.

# デバイスAを先にpush → 成功
$ git push origin master
   ba48c62..f0be52e  master -> master

# デバイスBをpush → 拒否される
$ git push origin master
 ! [rejected]  master -> master (fetch first)

# デバイスBがpull（マージを試み、衝突）
$ git pull origin master --no-rebase
Auto-merging Daily Notes/2026-08-26.md
CONFLICT (content): Merge conflict in Daily Notes/2026-08-26.md

# ノートの中身（Obsidianで開くとこのまま見える）
# 2026-08-26

- 08:00 起床
<<<<<<< HEAD
- 09:15 買い物メモ
=======
- 09:00 会議メモ
>>>>>>> f0be52e...

No data is lost, but the note opens in Obsidian with the conflict markers still in it — easy to misread as your own text if you don't notice. Resolving it means understanding what <<<<<<<, =======, and >>>>>>> mean, editing by hand, and committing again. Even with a plugin like Obsidian Git handling the sync, this final resolve step still requires knowing Git.

Keeps one version, exiles the other to a separate file

Running the same scenario — two Syncthing v1.27.2 instances (installed via apt) paired directly over local TCP — broke in a completely different way from Git.

# 同期再開後のvault-a
Daily Notes/2026-08-26.md
Daily Notes/2026-08-26.sync-conflict-20260825-212901-P2RW67Y.md

# 2026-08-26.md（採用された側）
# 2026-08-26

- 08:00 起床
- 09:15 買い物メモ（デバイスBで追記）

# 2026-08-26.sync-conflict-....md（退避された側）
# 2026-08-26

- 08:00 起床
- 09:00 会議メモ（デバイスAで追記）

Syncthing automatically keeps one version under the original filename and saves the other as a separate note named *.sync-conflict-timestamp-deviceID.md. No markers end up mixed into the text, and no Git knowledge is needed. But nothing gets merged automatically — miss the exiled note and the same topic stays split across two files. Unfamiliar filenames piling up in vault search is a real, if minor, cost of this approach.

Apple's own guide describes numbered duplicate files

Apple's own Mac Help guide describes a conflict-resolution dialog for iCloud Drive documents: you can keep multiple versions, and each gets a numbered filename like "Seven Wonders" and "Seven Wonders 2". That dialog, however, is documented for apps using Apple's document-versioning API (e.g. Pages) — there's no guarantee the same dialog appears for an app like Obsidian that reads and writes the filesystem directly. This environment has no macOS/iOS, so we could not test Obsidian plus iCloud Drive hands-on.

The sync-lag issue covered in the daily-note article — where the write is instant but propagation takes seconds — is a separate phenomenon from a true conflict. Knowing both speeds up diagnosing iCloud trouble.

The resolution algorithm isn't published; Version History is the safety net

The official help (obsidian.md/help/sync, fetched August 26, 2026) doesn't spell out which version wins on simultaneous edits. It does warn, in its own words, that "if you are using Obsidian Sync alongside other cloud storage providers, such as Dropbox, Google Drive, or OneDrive, please back up your vault to prevent sync conflicts" — so the concept of a conflict clearly exists here too. The documented recovery path is Version History: pick a past version of a note from a list and restore it. Retention is 1 month on Standard, 12 months on Plus, and 2 weeks for attachments regardless of plan.

Obsidian Sync requires payment to sign up, so we could not create an account or reproduce a real conflict in this environment.