feat: HTTP-based Yield routing (no DNS server required)

- Updated yield_dns.py to support A-record verification (simplest method!)
- A-record pointing to 46.235.147.194 is now the primary verification method
- Added Nginx catch-all config for yield domains
- DNS schema updated with method and actual_a fields
- CoreDNS installed but Port 53 blocked by hosting provider

backend/app/api/yield_domains.py

@@ -527,8 +527,10 @@ async def verify_domain_dns(
     return DNSVerificationResult(
         domain=domain.domain,
         verified=verified,
+        method=check.method,
         expected_ns=settings.yield_nameserver_list,
-        actual_ns=actual_ns,
+        actual_ns=check.actual_ns,
+        actual_a=check.actual_a,
         cname_ok=check.cname_ok if verified else False,
         error=error,
         checked_at=datetime.utcnow(),

backend/app/schemas/yield_domain.py

@@ -242,9 +242,11 @@ class DNSVerificationResult(BaseModel):
     """Result of DNS verification check."""
     domain: str
     verified: bool
+    method: Optional[str] = None  # "a_record" | "cname" | "nameserver"
     
     expected_ns: list[str]
     actual_ns: list[str]
+    actual_a: list[str] = []  # A-records found for the domain
     
     cname_ok: bool = False
     

backend/app/services/dns_zone_manager.py

@@ -0,0 +1,255 @@
+"""
+DNS Zone Manager for Pounce Yield.
+
+Manages CoreDNS zone files for yield domains.
+When a domain is activated for yield, we add it to the zone file.
+When deactivated, we remove it.
+"""
+
+import logging
+import os
+import re
+import subprocess
+from datetime import datetime
+from pathlib import Path
+from typing import Optional
+
+from app.config import get_settings
+
+logger = logging.getLogger(__name__)
+settings = get_settings()
+
+# CoreDNS zone file path
+ZONE_FILE = Path("/opt/coredns/zones/db.yield")
+SERVER_IP = "46.235.147.194"
+
+
+def _get_serial() -> str:
+    """Generate zone serial in YYYYMMDDNN format."""
+    today = datetime.utcnow().strftime("%Y%m%d")
+    # Read current serial and increment if same day
+    if ZONE_FILE.exists():
+        content = ZONE_FILE.read_text()
+        match = re.search(r"(\d{8})(\d{2})\s*;\s*Serial", content)
+        if match:
+            existing_date = match.group(1)
+            existing_nn = int(match.group(2))
+            if existing_date == today:
+                return f"{today}{(existing_nn + 1):02d}"
+    return f"{today}01"
+
+
+def _generate_zone_file(domains: list[str]) -> str:
+    """Generate the complete zone file content."""
+    serial = _get_serial()
+    
+    zone_content = f"""; Pounce Yield DNS Zone
+; Auto-generated by dns_zone_manager.py
+; Last updated: {datetime.utcnow().isoformat()}Z
+
+$TTL 300
+$ORIGIN yield.pounce.ch.
+
+@       IN      SOA     ns1.pounce.ch. admin.pounce.ch. (
+                        {serial} ; Serial (YYYYMMDDNN)
+                        3600       ; Refresh (1 hour)
+                        600        ; Retry (10 minutes)
+                        604800     ; Expire (1 week)
+                        300        ; Minimum TTL (5 minutes)
+                        )
+
+; Nameservers
+@       IN      NS      ns1.pounce.ch.
+@       IN      NS      ns2.pounce.ch.
+
+; A record for the zone apex
+@       IN      A       {SERVER_IP}
+
+; Wildcard - all subdomains point to our server
+*       IN      A       {SERVER_IP}
+
+; ============================================
+; YIELD DOMAINS (auto-managed)
+; ============================================
+"""
+    
+    for domain in sorted(set(domains)):
+        # Ensure domain ends with a dot (FQDN format)
+        fqdn = domain.lower().strip()
+        if not fqdn.endswith("."):
+            fqdn += "."
+        zone_content += f"{fqdn:<30} IN      A       {SERVER_IP}\n"
+    
+    return zone_content
+
+
+def add_yield_domain(domain: str) -> bool:
+    """
+    Add a domain to the yield DNS zone.
+    
+    Returns True if successful, False otherwise.
+    """
+    if not ZONE_FILE.exists():
+        logger.warning(f"Zone file not found: {ZONE_FILE}. CoreDNS may not be installed.")
+        return False
+    
+    try:
+        # Read current domains from zone file
+        content = ZONE_FILE.read_text()
+        domains = _parse_domains_from_zone(content)
+        
+        # Add new domain
+        domain_clean = domain.lower().strip().rstrip(".")
+        if domain_clean not in domains:
+            domains.append(domain_clean)
+            
+            # Write updated zone
+            new_content = _generate_zone_file(domains)
+            ZONE_FILE.write_text(new_content)
+            
+            # Reload CoreDNS
+            _reload_coredns()
+            
+            logger.info(f"Added yield domain to DNS: {domain_clean}")
+        else:
+            logger.info(f"Domain already in DNS zone: {domain_clean}")
+        
+        return True
+        
+    except Exception as e:
+        logger.error(f"Failed to add domain {domain} to DNS: {e}")
+        return False
+
+
+def remove_yield_domain(domain: str) -> bool:
+    """
+    Remove a domain from the yield DNS zone.
+    
+    Returns True if successful, False otherwise.
+    """
+    if not ZONE_FILE.exists():
+        logger.warning(f"Zone file not found: {ZONE_FILE}")
+        return False
+    
+    try:
+        content = ZONE_FILE.read_text()
+        domains = _parse_domains_from_zone(content)
+        
+        domain_clean = domain.lower().strip().rstrip(".")
+        if domain_clean in domains:
+            domains.remove(domain_clean)
+            
+            new_content = _generate_zone_file(domains)
+            ZONE_FILE.write_text(new_content)
+            
+            _reload_coredns()
+            
+            logger.info(f"Removed yield domain from DNS: {domain_clean}")
+        
+        return True
+        
+    except Exception as e:
+        logger.error(f"Failed to remove domain {domain} from DNS: {e}")
+        return False
+
+
+def sync_yield_domains(domains: list[str]) -> bool:
+    """
+    Sync all yield domains to the DNS zone.
+    
+    Replaces all existing yield domain entries with the provided list.
+    """
+    if not ZONE_FILE.parent.exists():
+        logger.warning(f"Zone directory not found: {ZONE_FILE.parent}")
+        return False
+    
+    try:
+        clean_domains = [d.lower().strip().rstrip(".") for d in domains]
+        new_content = _generate_zone_file(clean_domains)
+        
+        # Ensure directory exists
+        ZONE_FILE.parent.mkdir(parents=True, exist_ok=True)
+        ZONE_FILE.write_text(new_content)
+        
+        _reload_coredns()
+        
+        logger.info(f"Synced {len(clean_domains)} yield domains to DNS")
+        return True
+        
+    except Exception as e:
+        logger.error(f"Failed to sync yield domains: {e}")
+        return False
+
+
+def _parse_domains_from_zone(content: str) -> list[str]:
+    """Extract yield domain names from zone file content."""
+    domains = []
+    
+    # Look for lines after "YIELD DOMAINS" marker
+    in_yield_section = False
+    for line in content.split("\n"):
+        if "YIELD DOMAINS" in line:
+            in_yield_section = True
+            continue
+        
+        if in_yield_section and line.strip() and not line.strip().startswith(";"):
+            # Parse: domain.tld.     IN      A       IP
+            match = re.match(r"^([a-z0-9.-]+)\.\s+IN\s+A\s+", line, re.IGNORECASE)
+            if match:
+                domain = match.group(1).rstrip(".")
+                # Skip wildcards and pounce domains
+                if domain != "*" and "pounce" not in domain:
+                    domains.append(domain)
+    
+    return domains
+
+
+def _reload_coredns() -> bool:
+    """Reload CoreDNS to pick up zone changes."""
+    try:
+        # Send SIGUSR1 to reload zone files without restart
+        result = subprocess.run(
+            ["systemctl", "reload", "coredns"],
+            capture_output=True,
+            text=True,
+            timeout=10
+        )
+        if result.returncode != 0:
+            # Try restart as fallback
+            subprocess.run(
+                ["systemctl", "restart", "coredns"],
+                capture_output=True,
+                text=True,
+                timeout=30
+            )
+        return True
+    except Exception as e:
+        logger.warning(f"Could not reload CoreDNS: {e}")
+        return False
+
+
+def check_coredns_status() -> dict:
+    """Check if CoreDNS is running and healthy."""
+    status = {
+        "installed": ZONE_FILE.parent.exists(),
+        "running": False,
+        "zone_file_exists": ZONE_FILE.exists(),
+        "domain_count": 0,
+    }
+    
+    try:
+        result = subprocess.run(
+            ["systemctl", "is-active", "coredns"],
+            capture_output=True,
+            text=True,
+            timeout=5
+        )
+        status["running"] = result.stdout.strip() == "active"
+    except Exception:
+        pass
+    
+    if status["zone_file_exists"]:
+        content = ZONE_FILE.read_text()
+        status["domain_count"] = len(_parse_domains_from_zone(content))
+    
+    return status

backend/app/services/yield_dns.py

@@ -2,8 +2,9 @@
 Yield DNS verification helpers.
 
 Production-grade DNS checks for the Yield Connect flow:
-- Option A (recommended): Nameserver delegation to our nameservers
-- Option B (simpler): CNAME/ALIAS to a shared target
+- Option A: A-record pointing directly to our server IP (simplest!)
+- Option B: CNAME/ALIAS to yield.pounce.ch
+- Option C: Nameserver delegation to our nameservers (requires DNS server)
 """
 
 from __future__ import annotations
@@ -14,11 +15,16 @@ from typing import Optional
 import dns.resolver
 
 
+# Our server IP - domains with A-record pointing here are verified
+YIELD_SERVER_IP = "46.235.147.194"
+
+
 @dataclass(frozen=True)
 class YieldDNSCheckResult:
     verified: bool
-    method: Optional[str]  # "nameserver" | "cname" | None
+    method: Optional[str]  # "a_record" | "cname" | "nameserver" | None
     actual_ns: list[str]
+    actual_a: list[str]
     cname_ok: bool
     error: Optional[str]
 
@@ -37,7 +43,6 @@ def _normalize_host(host: str) -> str:
 def _resolve_ns(domain: str) -> list[str]:
     r = _resolver()
     answers = r.resolve(domain, "NS")
-    # NS answers are RRset with .target
     return sorted({_normalize_host(str(rr.target)) for rr in answers})
 
 
@@ -57,112 +62,108 @@ def verify_yield_dns(domain: str, expected_nameservers: list[str], cname_target:
     """
     Verify that a domain is connected for Yield.
 
-    We accept:
-    - Nameserver delegation (NS contains all expected nameservers), OR
-    - CNAME/ALIAS to `cname_target` (either CNAME matches, or A records match target A records)
+    We accept (in order of simplicity):
+    1. A-record pointing directly to our server IP (46.235.147.194)
+    2. CNAME/ALIAS to `cname_target` (yield.pounce.ch)
+    3. Nameserver delegation (NS contains all expected nameservers)
     """
     domain = _normalize_host(domain)
     expected_ns = sorted({_normalize_host(ns) for ns in expected_nameservers if ns})
     target = _normalize_host(cname_target)
+    actual_ns: list[str] = []
+    actual_a: list[str] = []
 
     if not domain:
         return YieldDNSCheckResult(
             verified=False,
             method=None,
             actual_ns=[],
+            actual_a=[],
             cname_ok=False,
             error="Domain is empty",
         )
-    if not expected_ns and not target:
-        return YieldDNSCheckResult(
-            verified=False,
-            method=None,
-            actual_ns=[],
-            cname_ok=False,
-            error="Yield DNS is not configured on server",
-        )
 
-    # Option A: NS delegation
+    # Option A: Direct A-record to our server IP (SIMPLEST!)
     try:
-        actual_ns = _resolve_ns(domain)
-        if expected_ns and set(expected_ns).issubset(set(actual_ns)):
+        actual_a = _resolve_a(domain)
+        if YIELD_SERVER_IP in actual_a:
             return YieldDNSCheckResult(
                 verified=True,
-                method="nameserver",
-                actual_ns=actual_ns,
+                method="a_record",
+                actual_ns=[],
+                actual_a=actual_a,
                 cname_ok=False,
                 error=None,
             )
     except (dns.resolver.NXDOMAIN, dns.resolver.NoAnswer):
-        actual_ns = []
+        pass
     except Exception as e:
         return YieldDNSCheckResult(
             verified=False,
             method=None,
             actual_ns=[],
+            actual_a=[],
             cname_ok=False,
             error=str(e),
         )
 
-    # Option B: CNAME / ALIAS
-    if not target:
-        return YieldDNSCheckResult(
-            verified=False,
-            method=None,
-            actual_ns=actual_ns,
-            cname_ok=False,
-            error="Yield CNAME target is not configured on server",
-        )
+    # Option B: CNAME to yield.pounce.ch
+    if target:
+        try:
+            cnames = _resolve_cname(domain)
+            if any(c == target for c in cnames):
+                return YieldDNSCheckResult(
+                    verified=True,
+                    method="cname",
+                    actual_ns=[],
+                    actual_a=actual_a,
+                    cname_ok=True,
+                    error=None,
+                )
+        except (dns.resolver.NXDOMAIN, dns.resolver.NoAnswer):
+            pass
+        except Exception:
+            pass
+        
+        # Also check if A-records match target's A-records (ALIAS/ANAME flattening)
+        try:
+            target_as = set(_resolve_a(target))
+            if target_as and actual_a and set(actual_a).issubset(target_as):
+                return YieldDNSCheckResult(
+                    verified=True,
+                    method="cname",
+                    actual_ns=[],
+                    actual_a=actual_a,
+                    cname_ok=True,
+                    error=None,
+                )
+        except Exception:
+            pass
 
-    # 1) Direct CNAME check (works for subdomain CNAME setups)
-    try:
-        cnames = _resolve_cname(domain)
-        if any(c == target for c in cnames):
-            return YieldDNSCheckResult(
-                verified=True,
-                method="cname",
-                actual_ns=actual_ns,
-                cname_ok=True,
-                error=None,
-            )
-    except (dns.resolver.NXDOMAIN, dns.resolver.NoAnswer):
-        pass
-    except Exception as e:
-        return YieldDNSCheckResult(
-            verified=False,
-            method=None,
-            actual_ns=actual_ns,
-            cname_ok=False,
-            error=str(e),
-        )
-
-    # 2) ALIAS/ANAME flattening: compare A records against target A records
-    try:
-        target_as = set(_resolve_a(target))
-        domain_as = set(_resolve_a(domain))
-        if target_as and domain_as and domain_as.issubset(target_as):
-            return YieldDNSCheckResult(
-                verified=True,
-                method="cname",
-                actual_ns=actual_ns,
-                cname_ok=True,
-                error=None,
-            )
-    except (dns.resolver.NXDOMAIN, dns.resolver.NoAnswer):
-        pass
-    except Exception as e:
-        return YieldDNSCheckResult(
-            verified=False,
-            method=None,
-            actual_ns=actual_ns,
-            cname_ok=False,
-            error=str(e),
-        )
+    # Option C: NS delegation (requires DNS server on Port 53)
+    if expected_ns:
+        try:
+            actual_ns = _resolve_ns(domain)
+            if set(expected_ns).issubset(set(actual_ns)):
+                return YieldDNSCheckResult(
+                    verified=True,
+                    method="nameserver",
+                    actual_ns=actual_ns,
+                    actual_a=actual_a,
+                    cname_ok=False,
+                    error=None,
+                )
+        except (dns.resolver.NXDOMAIN, dns.resolver.NoAnswer):
+            pass
+        except Exception:
+            pass
 
+    # Not verified
     return YieldDNSCheckResult(
         verified=False,
         method=None,
         actual_ns=actual_ns,
+        actual_a=actual_a,
         cname_ok=False,
         error=None,
     )

backend/scripts/setup_dns_server.sh

@@ -0,0 +1,180 @@
+#!/bin/bash
+# ============================================================================
+# Pounce DNS Server Setup (CoreDNS)
+# ============================================================================
+# This script sets up CoreDNS as an authoritative DNS server for Yield domains.
+# Users point their domains' NS records to ns1.pounce.ch and ns2.pounce.ch,
+# which both resolve to this server's IP.
+#
+# Usage: sudo bash setup_dns_server.sh
+# ============================================================================
+
+set -e
+
+echo "=========================================="
+echo "Pounce DNS Server Setup (CoreDNS)"
+echo "=========================================="
+
+# Check if running as root
+if [ "$EUID" -ne 0 ]; then
+    echo "ERROR: Please run as root (sudo)"
+    exit 1
+fi
+
+SERVER_IP="46.235.147.194"
+COREDNS_VERSION="1.11.1"
+COREDNS_DIR="/opt/coredns"
+ZONES_DIR="/opt/coredns/zones"
+
+echo "[1/6] Installing dependencies..."
+apt-get update -qq
+apt-get install -y -qq wget curl jq
+
+echo "[2/6] Downloading CoreDNS ${COREDNS_VERSION}..."
+mkdir -p "$COREDNS_DIR"
+cd "$COREDNS_DIR"
+
+if [ ! -f "coredns" ]; then
+    wget -q "https://github.com/coredns/coredns/releases/download/v${COREDNS_VERSION}/coredns_${COREDNS_VERSION}_linux_amd64.tgz"
+    tar -xzf "coredns_${COREDNS_VERSION}_linux_amd64.tgz"
+    rm "coredns_${COREDNS_VERSION}_linux_amd64.tgz"
+    chmod +x coredns
+fi
+
+echo "[3/6] Creating zone directory..."
+mkdir -p "$ZONES_DIR"
+
+echo "[4/6] Creating CoreDNS config (Corefile)..."
+cat > "$COREDNS_DIR/Corefile" << 'COREFILE'
+# CoreDNS Configuration for Pounce Yield
+# Serves authoritative DNS for delegated yield domains
+
+# Default zone - serves A record pointing to our server
+. {
+    # Log all queries for debugging
+    log
+    
+    # Serve zones from files
+    file /opt/coredns/zones/db.yield {
+        reload 30s
+    }
+    
+    # Health check endpoint
+    health :8053
+    
+    # Prometheus metrics
+    prometheus :9153
+    
+    # Forward unknown queries (shouldn't happen for authoritative)
+    forward . 8.8.8.8 8.8.4.4 {
+        max_concurrent 1000
+    }
+    
+    # Cache responses
+    cache 300
+    
+    # Error handling
+    errors
+}
+COREFILE
+
+echo "[5/6] Creating initial zone file..."
+cat > "$ZONES_DIR/db.yield" << ZONEFILE
+; Pounce Yield DNS Zone
+; This file is dynamically updated by the Pounce backend
+; DO NOT EDIT MANUALLY - changes will be overwritten
+
+\$TTL 300
+\$ORIGIN yield.pounce.ch.
+
+@       IN      SOA     ns1.pounce.ch. admin.pounce.ch. (
+                        $(date +%Y%m%d)01 ; Serial (YYYYMMDDNN)
+                        3600       ; Refresh (1 hour)
+                        600        ; Retry (10 minutes)
+                        604800     ; Expire (1 week)
+                        300        ; Minimum TTL (5 minutes)
+                        )
+
+; Nameservers
+@       IN      NS      ns1.pounce.ch.
+@       IN      NS      ns2.pounce.ch.
+
+; A record for the zone apex
+@       IN      A       ${SERVER_IP}
+
+; Wildcard - all subdomains point to our server
+*       IN      A       ${SERVER_IP}
+
+; ============================================
+; YIELD DOMAINS
+; Add domains below in format:
+; domainname    IN      A       ${SERVER_IP}
+; ============================================
+
+; Example (uncomment to test):
+; akaya.ch.     IN      A       ${SERVER_IP}
+
+ZONEFILE
+
+echo "[6/6] Creating systemd service..."
+cat > /etc/systemd/system/coredns.service << 'SERVICE'
+[Unit]
+Description=CoreDNS DNS Server
+Documentation=https://coredns.io
+After=network.target
+
+[Service]
+Type=simple
+User=root
+WorkingDirectory=/opt/coredns
+ExecStart=/opt/coredns/coredns -conf /opt/coredns/Corefile
+ExecReload=/bin/kill -SIGUSR1 $MAINPID
+Restart=on-failure
+RestartSec=5s
+LimitNOFILE=1048576
+LimitNPROC=512
+
+# Security
+CapabilityBoundingSet=CAP_NET_BIND_SERVICE
+AmbientCapabilities=CAP_NET_BIND_SERVICE
+NoNewPrivileges=true
+
+[Install]
+WantedBy=multi-user.target
+SERVICE
+
+echo "[7/6] Opening firewall port 53..."
+if command -v ufw &> /dev/null; then
+    ufw allow 53/tcp
+    ufw allow 53/udp
+    echo "UFW: Port 53 opened"
+elif command -v firewall-cmd &> /dev/null; then
+    firewall-cmd --permanent --add-port=53/tcp
+    firewall-cmd --permanent --add-port=53/udp
+    firewall-cmd --reload
+    echo "firewalld: Port 53 opened"
+else
+    echo "WARNING: No firewall detected. Make sure port 53 is open!"
+fi
+
+echo "[8/6] Starting CoreDNS..."
+systemctl daemon-reload
+systemctl enable coredns
+systemctl start coredns
+
+echo ""
+echo "=========================================="
+echo "✅ CoreDNS installed and running!"
+echo "=========================================="
+echo ""
+echo "Status: $(systemctl is-active coredns)"
+echo "Config: $COREDNS_DIR/Corefile"
+echo "Zones:  $ZONES_DIR/db.yield"
+echo ""
+echo "To add a yield domain, append to $ZONES_DIR/db.yield:"
+echo "  akaya.ch.     IN      A       $SERVER_IP"
+echo ""
+echo "Then reload: systemctl reload coredns"
+echo ""
+echo "Test with: dig @localhost akaya.ch"
+echo "=========================================="

backend/scripts/setup_yield_nginx.sh

@@ -0,0 +1,98 @@
+#!/bin/bash
+# ============================================================================
+# Pounce Yield HTTP Routing Setup
+# ============================================================================
+# This sets up Nginx to catch-all domains pointing to our server
+# and route them to the Pounce backend for Yield landing pages.
+#
+# Instead of Nameserver delegation (which requires Port 53),
+# users simply set an A-record pointing to our IP.
+#
+# Usage: sudo bash setup_yield_nginx.sh
+# ============================================================================
+
+set -e
+
+echo "=========================================="
+echo "Pounce Yield HTTP Routing Setup"
+echo "=========================================="
+
+# Check if running as root
+if [ "$EUID" -ne 0 ]; then
+    echo "ERROR: Please run as root (sudo)"
+    exit 1
+fi
+
+NGINX_CONF="/etc/nginx/sites-available/yield-catchall"
+SERVER_IP="46.235.147.194"
+
+echo "[1/3] Creating Nginx catch-all config for Yield..."
+
+cat > "$NGINX_CONF" << 'NGINX'
+# Pounce Yield Catch-All Server
+# This catches all domains pointing to our server that aren't pounce.ch
+# and routes them to the Yield routing backend.
+
+server {
+    listen 80 default_server;
+    listen [::]:80 default_server;
+    
+    # Catch all hostnames except pounce.ch
+    server_name _;
+    
+    # Skip if it's pounce.ch or www.pounce.ch
+    if ($host ~* ^(www\.)?pounce\.ch$) {
+        return 444;  # Close connection, let the main server block handle it
+    }
+    
+    # Route all traffic to backend yield routing
+    location / {
+        # Rewrite to /api/v1/r/{hostname}
+        set $yield_domain $host;
+        
+        proxy_pass http://127.0.0.1:8000/api/v1/r/$yield_domain;
+        proxy_http_version 1.1;
+        proxy_set_header Host $host;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+        proxy_set_header X-Forwarded-Proto $scheme;
+        proxy_set_header X-Yield-Domain $host;
+        
+        # Handle errors gracefully
+        proxy_intercept_errors on;
+        error_page 404 502 503 504 = @yield_fallback;
+    }
+    
+    # Fallback for domains not configured in Yield
+    location @yield_fallback {
+        return 302 https://pounce.ch/yield?domain=$host;
+    }
+}
+NGINX
+
+echo "[2/3] Enabling site and testing config..."
+
+# Enable the site if not already
+if [ ! -f "/etc/nginx/sites-enabled/yield-catchall" ]; then
+    ln -sf "$NGINX_CONF" /etc/nginx/sites-enabled/yield-catchall
+fi
+
+# Test nginx config
+nginx -t
+
+echo "[3/3] Reloading Nginx..."
+systemctl reload nginx
+
+echo ""
+echo "=========================================="
+echo "✅ Yield HTTP Routing configured!"
+echo "=========================================="
+echo ""
+echo "How it works:"
+echo "1. User sets A-record for their domain to: $SERVER_IP"
+echo "2. When someone visits the domain, Nginx catches it"
+echo "3. Traffic is routed to /api/v1/r/{domain}"
+echo "4. Backend serves the Yield landing page"
+echo ""
+echo "No DNS server (Port 53) required!"
+echo "=========================================="