Usenet Configuration

Decypharr supports direct NNTP streaming from Usenet providers - no additional download client required.

How It Works

Decypharr connects directly to NNTP servers to:

1. Parse NZB files for segment information
2. Stream segments on-demand for playback
3. Download and assemble complete files

Provider Configuration

Add Provider

{
  "usenet": {
    "providers": [
      {
        "host": "news.provider.com",
        "port": 563,
        "username": "your_username",
        "password": "your_password",
        "ssl": true,
        "max_connections": 20,
        "priority": 1
      }
    ]
  }
}

Multiple Providers

Decypharr can use multiple providers with priority and failover:

{
  "usenet": {
    "providers": [
      {
        "host": "primary.news.com",
        "port": 563,
        "username": "user1",
        "password": "pass1",
        "ssl": true,
        "max_connections": 20,
        "priority": 1
      },
      {
        "host": "backup.news.com",
        "port": 563,
        "username": "user2",
        "password": "pass2",
        "ssl": true,
        "max_connections": 10,
        "priority": 2
      }
    ]
  }
}

Lower priority = higher preference.

Performance Tuning

Connection Limits

{
  "usenet": {
    "max_connections": 15
  }
}

• max_connections: Per-file/stream connection limit
• Provider max_connections: Per-provider limit

Example:

• Global: 15
• Provider A: 20
• Provider B: 10

→ Up to 15 connections per file, split between providers based on priority

Read-Ahead Buffer

{
  "usenet": {
    "read_ahead": "16MB"
  }
}

Prefetch buffer for smoother playback. Higher = smoother but more memory.

Processing Limits

{
  "usenet": {
    "max_concurrent_nzb": 2,
    "processing_timeout": "10m"
  }
}

• max_concurrent_nzb: How many NZBs to process in parallel
• processing_timeout: Mark as bad if processing exceeds this

Availability Checking

{
  "usenet": {
    "availability_sample_percent": 10
  }
}

Sample 10% of segments to check availability before downloading.

• 100: Check all segments (slow but accurate)
• 10: Check 10% (fast but may miss issues)
• 1: Quick check (recommended for large files)

Disk Buffer

{
  "usenet": {
    "disk_buffer_path": "/cache/usenet/streams"
  }
}

Streams use disk buffer for assembly. Ensure sufficient disk space.

Repair

{
  "usenet": {
    "skip_repair": false
  }
}

Arr Integration

Arrs send NZB files to Decypharr via the Sabnzbd API endpoint:

In Sonarr/Radarr:

1. Add Sabnzbd download client
2. Host: http://decypharr:8282
3. API Key: Your Decypharr API token
4. Category: sonarr / radarr

See Sabnzbd Integration for details.

Troubleshooting

Connection Failures

• Verify host/port/SSL settings
• Test manually: telnet news.provider.com 563
• Check provider status

Slow Streaming

1. Increase max_connections per provider
2. Increase global max_connections
3. Increase read_ahead buffer

Processing Timeouts

• Increase processing_timeout for large files
• Reduce availability_sample_percent for faster checks
• Increase max_concurrent_nzb if CPU allows

Incomplete Downloads

• Enable skip_repair: false for PAR2 repair
• Check provider retention (old files may be incomplete)
• Try backup provider if available

Example Configuration

Full Usenet config with optimal settings:

{
  "usenet": {
    "providers": [
      {
        "host": "us.news.provider.com",
        "port": 563,
        "username": "user",
        "password": "pass",
        "ssl": true,
        "max_connections": 30,
        "priority": 1
      }
    ],
    "max_connections": 15,
    "read_ahead": "32MB",
    "processing_timeout": "15m",
    "availability_sample_percent": 5,
    "max_concurrent_nzb": 3,
    "disk_buffer_path": "/cache/usenet",
    "skip_repair": false
  }
}