How to Monitor Your HAProxy Load Balancer with Vigilmon

HAProxy is the gold standard for high-availability load balancing. It routes traffic to hundreds of backend servers while maintaining near-zero downtime. But HAProxy itself needs to be monitored — and so do the backends it routes to. Here's how to set up comprehensive HAProxy monitoring with Vigilmon.

HAProxy Monitoring Layers

1. HAProxy process — is the load balancer itself reachable?
2. Frontend health — is the VIP/frontend accepting connections?
3. Backend health — are individual backend servers responding?
4. Routed services — are the end-user-facing services healthy?

Enable HAProxy Health Check Endpoint

Add a dedicated health endpoint to your HAProxy config:

frontend http-in
    bind *:80
    default_backend servers

    # Health check endpoint for Vigilmon
    acl health_check path /haproxy-health
    use_backend health_backend if health_check

backend health_backend
    http-request return status 200 content-type text/plain string "OK"

backend servers
    balance roundrobin
    option httpchk GET /health
    server web1 10.0.0.1:8080 check
    server web2 10.0.0.2:8080 check
    server web3 10.0.0.3:8080 check

Setting Up Vigilmon Monitors

Monitor 1: HAProxy Frontend Health

1. Sign in at vigilmon.online
2. + New Monitor → URL: https://yourdomain.com/haproxy-health
3. Check interval: 1 minute
4. Alert on: 2 consecutive failures

Monitor 2: End-User Service Health

Create additional monitors for your application endpoints:

https://api.yourdomain.com/health → API Monitor
https://yourdomain.com/ → Homepage Monitor

Monitor 3: SSL Certificate Tracking

Vigilmon automatically checks SSL certificates on HTTPS monitors. You'll get expiry alerts 30, 14, and 7 days before expiry.

Multi-Region Monitoring for HAProxy

For global HAProxy deployments, enable multi-region checks in Vigilmon:

• US East — verify primary datacenter
• EU West — verify European failover
• Asia Pacific — verify APAC presence

If only one region fails, it's likely a routing/BGP issue rather than HAProxy itself.

Alerting Configuration

Connect Vigilmon to your incident response stack:

Slack #ops → immediate team notification
PagerDuty → on-call escalation
Email → manager notification
Webhook → trigger automated failover script

The webhook integration lets you trigger automatic HAProxy failover when Vigilmon detects an issue.

Setting Up a Status Page

Vigilmon's public status pages let you communicate load balancer health to downstream teams or customers.

Conclusion

HAProxy + Vigilmon gives you multi-layer load balancer monitoring:

• ✅ HAProxy frontend health checks
• ✅ End-user service monitoring
• ✅ SSL certificate tracking
• ✅ Multi-region verification
• ✅ Automated alerting and incident management
• ✅ Public status pages

Get started in 5 minutes — no agent installation, no code changes. Free tier at vigilmon.online.