Troubleshooting

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Permission Denied Errors

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Symptom

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Diagnosis

1. Check what access was granted:
   nono run --allow-cwd --dry-run -- command
   
2. Query capabilities from inside the sandbox:
   # Check if a specific path is accessible
   nono run --allow-cwd -- nono why --self --path /tmp --op write --json
   
   # Human-readable output
   nono run --allow-cwd -- nono why --self --path ~/.ssh --op read
   
3. Run with verbose logging:
   nono run -vvv --allow-cwd -- command
   

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Common Causes

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Sensitive Paths

• ~/.ssh/ - SSH keys
• ~/.aws/ - AWS credentials
• ~/.gnupg/ - GPG keys
• ~/.kube/ - Kubernetes config
• ~/.docker/ - Docker credentials
• Shell history files
• Shell configuration files

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Network Connection Failed

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Symptom

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Possible Causes

1. Network explicitly blocked - You used --block-net flag
2. Actual network issue - DNS, firewall, or connectivity problem
3. Application-specific issue - App needs specific configuration

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Solutions

1. If you used --block-net, remove it:
   # Network is allowed by default
   nono run --allow-cwd -- curl https://example.com
   
2. Check if network is allowed from inside the sandbox:
   nono run --allow-cwd -- nono why --self --host example.com --json
   # Should show {"status":"allowed",...}
   
3. Test network outside nono:
   curl https://example.com
   # If this fails, it's not a nono issue
   

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Command Not Found

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Symptom

nono: command not found

error: No such file or directory: my-command

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Solutions

1. nono not in PATH:
   # Add to PATH
   export PATH="$PATH:/path/to/nono/target/release"
   
2. Target command not in PATH:
   # Use absolute path
   nono run --allow-cwd -- /usr/local/bin/my-command
   
   # Or ensure PATH is set correctly
   nono run --allow-cwd -- sh -c 'which my-command'
   

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Sandbox Initialization Failed

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Symptom

Error: Sandbox initialization failed: ...

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Linux (Landlock)

1. Check kernel version:
   uname -r
   # Must be 5.13+ for Landlock
   
2. Check Landlock is enabled:
   cat /sys/kernel/security/lsm
   # Should include "landlock"
   
3. Enable Landlock (if missing): Add lsm=landlock,... to kernel boot parameters

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macOS (Seatbelt)

1. Check macOS version:
   sw_vers
   # Should be 10.15 (Catalina) or later
   
2. Check for SIP issues: Some system integrity protection settings can interfere. This is rare.

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Dry Run Shows Different Paths

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Symptom

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Explanation

• Relative paths become absolute
• Symlinks are resolved
• .. and . are normalized

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Example

$ pwd
/home/user/project

$ nono run --allow-cwd --dry-run -- command
Capabilities:
  [rw] /home/user/project    # Resolved from "."

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Child Process Doesn’t Inherit Sandbox

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Symptom

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This Shouldn’t Happen

1. Verify the parent is sandboxed:
   # The --self flag only works inside a sandbox
   nono run --allow-cwd -- nono why --self --path /etc --op read
   # Should show current sandbox capabilities
   
2. Check if you’re testing correctly:
   # Parent and child are BOTH sandboxed
   nono run --allow-cwd -- sh -c 'sh -c "cat /etc/passwd"'
   # Should fail if /etc is not allowed
   

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Performance Issues

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Symptom

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Explanation

1. First run may be slower due to path canonicalization
2. Many file operations may show overhead from kernel permission checks

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Solutions

• Grant access to larger directories instead of many individual files
• Use --read for directories that don’t need write access (slightly faster path)

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Using nono why --self for Debugging

# Check if a path would be readable
nono run --allow-cwd -- nono why --self --path ~/.ssh --op read
# Output: DENIED - sensitive_path (SSH keys and config)

# Check if a path would be writable
nono run --allow . -- nono why --self --path ./src --op write
# Output: ALLOWED - Granted by: --allow .

# JSON output for programmatic use (useful for AI agents)
nono run --allow-cwd -- nono why --self --path /tmp --op write --json
# {"status":"denied","reason":"not_in_allowed_paths","suggestion":"--write /tmp"}

# Check network status
nono run --allow-cwd -- nono why --self --host api.openai.com
# Output: ALLOWED - network allowed by default

# Check network when blocked
nono run --allow-cwd --block-net -- nono why --self --host api.openai.com
# Output: DENIED - network_blocked

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Platform-Specific Issues

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macOS: “killed: 9” or Immediate Termination

nono run -vvv --allow-cwd -- command

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Linux: “Landlock not supported”

# Verify kernel version
uname -r

# Check LSM list
cat /sys/kernel/security/lsm

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Linux: Network Restrictions Not Working

# Check kernel version
uname -r

# If < 6.7, network filtering is unavailable via Landlock

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Using nono learn to Discover Required Paths

# Discover all paths accessed by your app
nono learn -- my-app

# Compare against an existing profile to see what's missing
nono learn --profile my-profile -- my-app

# Output as JSON for easy profile creation
nono learn --json -- my-app

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Example Workflow

1. Run learn mode to discover paths:
   nono learn -- opencode
   
2. Review the output to see which paths are needed:
   Read paths needed:
     /usr/share/locale-langpack
     /home/user/.config/opencode
   
   Write paths needed:
     /home/user/.cache/opencode
   
3. Add the paths to your nono command or profile:
   nono run --read /usr/share/locale-langpack --allow ~/.config/opencode -- opencode
   

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WSL2-Specific Issues

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Sandbox initialization: EBUSY on seccomp

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Credential proxy refused on WSL2

• Use --env-credential instead of --credential (env var injection works normally)
• Opt in to degraded proxy mode with wsl2_proxy_policy: "insecure_proxy" in your profile’s security config (details)

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Per-port network filtering unavailable

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Verifying WSL2 compatibility

nono setup --check-only

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Getting Help

1. Search existing issues: GitHub Issues
2. Open a new issue with:
   • nono version (nono --version)
   • OS and kernel version
   • Full command that failed
   • Error message
   • Output of nono run --dry-run with same flags