Rclone Two Way Sync With OneDrive @ Shiyu

I wanted to sync a folder from an external hard drive to OneDrive as a backup. But during setup, I realized it's not as straightforward on macOS as I expected.

The OneDrive client on macOS is limited to a single sync folder, while the folder I want to sync is on an external drive. I tried to use a symlink to mount that folder into the OneDrive directory. However, this approach is not supported on macOS.

With the help of AI, I found Rclone. It can bypass the limitations of the OneDrive client and sync any folder directly to the cloud.

What bisync does

Rclone has a command called bisync that keeps two locations in sync:

Add a file locally, it shows up in the cloud
Add a file in the cloud, it shows up locally
Delete a file on either side, it gets deleted on the other

Install rclone

brew install rclone

BASH

Connect to OneDrive

rclone config

BASH

Follow the steps:

Type n to create a new config
Name it onedrive
Choose Microsoft OneDrive
Press enter to skip client_id and secret
Choose your account type (personal or business)
Log in in the browser when it opens
Finish setup

Check if it works:

rclone lsd onedrive:

BASH

If you see your folders, it is ready.

First-time setup

Before running bisync for the first time, you need to pass --resync to build the initial baseline. This tells rclone to scan both sides and record their current state. Future syncs compare against this snapshot to detect changes.

If the two sides already have different files, the result might not be what you expect.
Run with --dry-run first to preview what will happen. Back up anything important before proceeding.

I also recommend using --check-access. It requires a file called RCLONE_TEST in both folders. If it is missing, the sync will stop. This is a simple safeguard against mistakes like a wrong path or an unmounted drive. Create the files first:

# Create locally
touch /Users/xin/Documents/SyncTest/RCLONE_TEST
 
# Create on OneDrive
rclone touch onedrive:SyncTest/RCLONE_TEST

BASH

Then run the initial sync:

rclone bisync /Users/xin/Documents/SyncTest onedrive:SyncTest \
  --resync \
  --check-access \
  --recover \
  --resilient \
  --create-empty-src-dirs \
  --max-delete 50 \
  --conflict-resolve newer \
  --verbose \
  --progress

BASH

Here is what each flag does:

Flag	What it does
`--resync`	Rebuilds the sync baseline. Use on first run or after a corrupted state
`--check-access`	Checks for `RCLONE_TEST` on both sides before doing anything
`--recover`	Tries to recover from a previous interrupted sync instead of failing
`--resilient`	Keeps going if a single file fails, instead of stopping everything
`--create-empty-src-dirs`	Syncs empty folder creation and deletion
`--max-delete`	Limits how many files can be deleted in one run
`--conflict-resolve newer`	Keeps the newer file when both sides changed the same file
`--track-renames`	Detects renames instead of treating them as a delete and re-upload
`--verbose`	Prints detailed output, useful for debugging
`--log-file`	Writes output to a log file
`--progress`	Shows live progress while syncing
`--dry-run`	Simulates the sync without making any changes

Daily sync

After the first run, drop --resync and add --track-renames:

rclone bisync /Users/xin/Documents/SyncTest onedrive:SyncTest \
  --check-access \
  --recover \
  --resilient \
  --create-empty-src-dirs \
  --max-delete 50 \
  --conflict-resolve newer \
  --track-renames \
  --log-file=/tmp/rclone-bisync.log \
  --progress

BASH

Sync script

Typing that command every time is tedious. I do not need automatic or scheduled syncing, so I wrote a short script to run it manually when I want.

#!/bin/bash
 
LOCAL="/Users/xin/Documents/SyncTest"
REMOTE="onedrive:SyncTest"
LOG_FILE="/tmp/rclone-bisync.log"
 
echo "🔄 Syncing $LOCAL <-> $REMOTE"
 
rclone bisync "$LOCAL" "$REMOTE" \
  --check-access \
  --recover \
  --resilient \
  --create-empty-src-dirs \
  --max-delete 50 \
  --conflict-resolve newer \
  --track-renames \
  --log-file="$LOG_FILE" \
  --progress
 
if [ $? -eq 0 ]; then
  echo "✅ Done"
else
  echo "❌ Sync failed. Check the log: $LOG_FILE"
  exit 1
fi

BASH

Make it executable before running:

chmod +x sync.sh

BASH

Just Enjoy it.

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I wanted to sync a folder from an external hard drive to OneDrive as a backup. But during setup, I realized it's not as straightforward on macOS as I expected.

With the help of AI, I found Rclone. It can bypass the limitations of the OneDrive client and sync any folder directly to the cloud.

What bisync does

Rclone has a command called bisync that keeps two locations in sync:

Add a file locally, it shows up in the cloud
Add a file in the cloud, it shows up locally
Delete a file on either side, it gets deleted on the other

Install rclone

brew install rclone

BASH

Connect to OneDrive

rclone config

BASH

Follow the steps:

Type n to create a new config
Name it onedrive
Choose Microsoft OneDrive
Press enter to skip client_id and secret
Choose your account type (personal or business)
Log in in the browser when it opens
Finish setup

Check if it works:

rclone lsd onedrive:

BASH

If you see your folders, it is ready.

First-time setup

If the two sides already have different files, the result might not be what you expect.
Run with --dry-run first to preview what will happen. Back up anything important before proceeding.

# Create locally
touch /Users/xin/Documents/SyncTest/RCLONE_TEST
 
# Create on OneDrive
rclone touch onedrive:SyncTest/RCLONE_TEST

BASH

Then run the initial sync:

rclone bisync /Users/xin/Documents/SyncTest onedrive:SyncTest \
  --resync \
  --check-access \
  --recover \
  --resilient \
  --create-empty-src-dirs \
  --max-delete 50 \
  --conflict-resolve newer \
  --verbose \
  --progress

BASH

Here is what each flag does:

Flag	What it does
`--resync`	Rebuilds the sync baseline. Use on first run or after a corrupted state
`--check-access`	Checks for `RCLONE_TEST` on both sides before doing anything
`--recover`	Tries to recover from a previous interrupted sync instead of failing
`--resilient`	Keeps going if a single file fails, instead of stopping everything
`--create-empty-src-dirs`	Syncs empty folder creation and deletion
`--max-delete`	Limits how many files can be deleted in one run
`--conflict-resolve newer`	Keeps the newer file when both sides changed the same file
`--track-renames`	Detects renames instead of treating them as a delete and re-upload
`--verbose`	Prints detailed output, useful for debugging
`--log-file`	Writes output to a log file
`--progress`	Shows live progress while syncing
`--dry-run`	Simulates the sync without making any changes

Daily sync

After the first run, drop --resync and add --track-renames:

rclone bisync /Users/xin/Documents/SyncTest onedrive:SyncTest \
  --check-access \
  --recover \
  --resilient \
  --create-empty-src-dirs \
  --max-delete 50 \
  --conflict-resolve newer \
  --track-renames \
  --log-file=/tmp/rclone-bisync.log \
  --progress

BASH

Sync script

Typing that command every time is tedious. I do not need automatic or scheduled syncing, so I wrote a short script to run it manually when I want.

#!/bin/bash
 
LOCAL="/Users/xin/Documents/SyncTest"
REMOTE="onedrive:SyncTest"
LOG_FILE="/tmp/rclone-bisync.log"
 
echo "🔄 Syncing $LOCAL <-> $REMOTE"
 
rclone bisync "$LOCAL" "$REMOTE" \
  --check-access \
  --recover \
  --resilient \
  --create-empty-src-dirs \
  --max-delete 50 \
  --conflict-resolve newer \
  --track-renames \
  --log-file="$LOG_FILE" \
  --progress
 
if [ $? -eq 0 ]; then
  echo "✅ Done"
else
  echo "❌ Sync failed. Check the log: $LOG_FILE"
  exit 1
fi

BASH

Make it executable before running:

chmod +x sync.sh

BASH

Just Enjoy it.

Like this post?

Comment on