Your First Sync

With your configuration in place, it’s time to run your first sync and see NextDNS Blocker in action.

Understanding Sync

The config push command:

Reads your config.json blocklist
Evaluates each domain against the current time and its schedule
Adds/removes domains from your NextDNS denylist accordingly
Processes any pending unblock actions

Run a Dry Run First

Before making actual changes, preview what would happen:

nextdns-blocker config push --dry-run

Output example:

DRY RUN - No changes will be made

Evaluating domains at 2024-01-15 14:30:00 (America/New_York)...

  reddit.com
    Schedule: Mon-Fri 12:00-13:00, 18:00-22:00
    Current: Outside available hours
    Action: Would BLOCK

  twitter.com
    Schedule: Always available on weekends
    Current: Within available hours
    Action: Would UNBLOCK

Summary: 1 would block, 1 would unblock

Run the Actual Sync

When you’re ready to apply changes:

nextdns-blocker config push

Output:

Syncing domains...
  reddit.com: BLOCKED
  twitter.com: UNBLOCKED
Sync complete: 1 blocked, 1 unblocked

Verbose Mode

For more detailed output:

nextdns-blocker config push --verbose

Or use the shorthand:

nextdns-blocker config push -v

This shows:

Current timezone and time
Each domain’s schedule evaluation
API calls made
Cache hits/misses

Check Current Status

After syncing, verify the current state:

nextdns-blocker status

Output:

NextDNS Blocker Status
━━━━━━━━━━━━━━━━━━━━━━

Time: 2024-01-15 14:30:00 America/New_York

Blocklist (2 domains):
  ✗ reddit.com      BLOCKED   (until 18:00)
  ✓ twitter.com     AVAILABLE (until 22:00)

Allowlist (1 domain):
  ✓ aws.amazon.com  ALLOWED   (always)

System:
  Watchdog: Active
  Panic Mode: Inactive
  Pending Actions: 0

What Gets Synced

Blocklist Behavior

Condition	Action	Result
Outside schedule	Block	Added to NextDNS denylist
Within schedule	Unblock	Removed from denylist
No schedule (`null`)	Always block	Permanent denylist entry

Allowlist Behavior

Condition	Action	Result
No schedule	Always allow	Permanent allowlist entry
Within schedule	Allow	Added to NextDNS allowlist
Outside schedule	Remove	Removed from allowlist

Automatic Sync with Watchdog

Manual syncing works, but the watchdog automates this:

# Install watchdog (runs config push every 2 minutes)
nextdns-blocker watchdog install

# Check watchdog status
nextdns-blocker watchdog status

# View watchdog logs
tail -f ~/.local/share/nextdns-blocker/logs/cron.log

The watchdog:

Runs config push every 2 minutes
Restores itself if removed
Logs all activity
Can be temporarily disabled

Common Issues

”No domains configured”

Your blocklist is empty. Add domains:

nextdns-blocker config edit

“API authentication failed”

Your credentials are invalid. Re-run setup:

nextdns-blocker init

“Domain already in denylist”

The domain was manually added to NextDNS. NextDNS Blocker will manage it going forward, but you can verify in the NextDNS dashboard.

”Rate limit exceeded”

Too many API calls. Wait a minute and try again. The tool has built-in rate limiting, but rapid manual syncs can exceed limits.