Email Forwarding

Email forwarding turns Forge into an inbound mail receiver. Point your domain’s MX records at your Forge server, create forwarding rules, and email sent to @yourdomain.com lands in your personal inbox.

How It Works

External sender
    │
    │  SMTP (port 25)
    ▼
┌──────────────────────────┐
│  Forge Inbound SMTP       │
│  (smtp-server + mailparser)│
│                           │
│  1. Receives raw email    │
│  2. SPF check on sender   │
│  3. Spam scoring          │
│  4. Matches forward rule  │
│  5. Re-wraps & relays     │
└──────────┬───────────────┘
           │
           ▼
┌──────────────────────────┐
│  Forge Outbound SMTP      │
│  (nodemailer)             │
│                           │
│  Forwards to:             │
│  me@gmail.com             │
└──────────────────────────┘

Forge is a mail relay, not a mail server. It receives, filters, and forwards. It does not store email (beyond logs) or provide IMAP/POP3 access. Your destination inbox (Gmail, Proton, Fastmail) handles storage, search, and replies.

Prerequisites

1. Enable inbound email

# In your Forge .env:
FORGE_EMAIL_INBOUND_ENABLED=true
FORGE_EMAIL_INBOUND_PORT=25          # 25 for production, 2525 for testing

Restart Forge.

2. Open port 25

sudo ufw allow 25/tcp

Some VPS providers block port 25 by default. You may need to request unblocking:

• Hetzner: Unblocked by default
• DigitalOcean: Open a support ticket
• AWS Lightsail/EC2: Port 25 is permanently restricted — use SES instead
• Linode: Open a support ticket

3. Configure DNS

Add MX records to your domain:

Type  Name                   Value                          Priority
MX    mail.yourdomain.com    forge.yourserver.com.          10
A     forge.yourserver.com   YOUR_VPS_IP                    -
TXT   mail.yourdomain.com    "v=spf1 mx -all"              (SPF record)

Replace forge.yourserver.com with the hostname pointing to your Forge server, and YOUR_VPS_IP with the actual IP.

Creating Forwarding Rules

Go to System Settings → Email → Forwards → Add Forward.

Exact Match

Source:       support@yourdomain.com
Destination:  me@gmail.com
Spam filter:  Standard

Emails to support@yourdomain.com are forwarded to me@gmail.com.

Wildcard (Catch-All)

Source:       *@yourdomain.com
Destination:  me@gmail.com
Spam filter:  Standard

Any email to @yourdomain.com that doesn’t match an exact rule is forwarded to me@gmail.com. Only one wildcard per identity — create it last.

Rule Priority

Exact matches are checked first. The wildcard (if any) is checked last. If no rule matches, the email is silently dropped (not bounced, to avoid backscatter spam).

Spam Filtering

Forge scores every inbound email from 0–100:

Signal	Check
SPF validation	Did the sender’s IP match the domain’s SPF record?
Reverse DNS	Does the sender’s IP have a PTR record?
DNS blacklists	Is the sender IP on Spamhaus or similar DNSBL? (configurable)
Header heuristics	Missing Message-ID, malformed Date, mismatched From
Content signals	Known spam patterns in subject and body

Threshold modes:

Mode	Score threshold	Behavior
Off	N/A	Forward everything — no spam filtering
Standard (default)	60+	Drop if score exceeds 60
Strict	35+	Drop if score exceeds 35

Set the mode per forwarding rule in the dashboard.

Inbound Log

The Inbound Log tab shows all received emails:

Column	Description
From	Sender address
To	Recipient address (the forwarding address)
Subject	Email subject
Spam Score	0–100 spam probability
Action	forwarded or dropped
Time	When the email was received

Dropped emails are logged with their spam score — useful for tuning thresholds or investigating false positives.

Attachments

Inbound emails with attachments are forwarded with attachments intact (up to 25 MB total message size). Forge does not scan or modify attachment content.

Replies

Replies to forwarded emails go to the original sender, not to Forge. The Reply-To header is preserved from the original email. Forge does not rewrite headers.

To reply from your custom domain address (e.g., support@yourdomain.com), configure that address as a “Send mail as” alias in Gmail or your email client, using your SMTP server credentials.

Limits

Limit	Value
Max inbound message size	25 MB
Inbound rate limit	600 emails/minute per identity
Max forwarding rules per identity	50
Port (production)	25
Port (development)	2525

Troubleshooting

Problem	Likely cause	Fix
Emails not arriving	DNS MX records not propagated	Check with dig MX yourdomain.com. Wait up to 48 hours for DNS propagation.
Port 25 connection refused	VPS blocks port 25	Use FORGE_EMAIL_INBOUND_PORT=2525 for testing, or request unblock from VPS provider.
All emails dropped as spam	Spam threshold too strict	Lower threshold or set mode to “Off” temporarily to check if emails are arriving.
Forwarded email not in inbox	Destination spam filter	Check Gmail/Proton spam folder. Whitelist noreply@forge.yourserver.com.
SPF validation fails	Missing SPF record	Add "v=spf1 mx -all" TXT record to your domain.