Skip to content

Administrator Guide — NetCell MailGuard

NetCell MailGuard (nmg) is an SMTP security gateway distributed as a Debian package (Bookworm, amd64 + arm64). It is built on Postfix, rspamd, ClamAV, and a YARA sandbox, with active-active cluster support.

Contents

Section Description
Installation System requirements, installation, initial setup
Dashboard System overview, threat radar, traffic metrics
Domains & Routing Managing mail domains, transport routes, DKIM
Mail Configuration Postfix parameters, TLS, thresholds, all filter options
Quarantine Managing the quarantine queue — release, reject, allow-list
Mail Queue Monitor and control the active mail queue
Mail Logs & Trace Search logs, trace a message through all Postfix hops
Filters & Rules Sender filters, RBL, composites, phishing feeds, TLDs
Sandbox YARA analysis of attachments and URLs
Security Alerts IOC monitor, outbound guard, retroscan
DMARC Evaluating DMARC aggregate reports
Firewall Managing IP access rules
Bayes Training Spam and ham training, spam bursts, analytics
Reporting Traffic statistics and reports
Cluster Adding/removing nodes, cluster health
Users & Roles Managing admin users and API keys
Settings License, TLS, branding, auto-update, backup
Privacy (GDPR) Archiving rules, compliance

Quick Reference

# Service status
systemctl status nmg-api nmg-scheduler nmg-sandbox postfix rspamd

# Live logs
journalctl -u nmg-api -f

# Show Postfix queue
postqueue -p

# Test rspamd config
rspamadm configtest --strict