IBM HashiCorp Consul

Why HashiCorp Consul?

Traffic between services is the part of the estate that perimeter cybersecurity never sees: it never crosses a firewall, and it is usually unencrypted because it was assumed to be internal. A service mesh makes that traffic authenticated and inspectable — which is also the first place worth looking after any compromise.

Microservices communication is often unencrypted. Manual service discovery doesn’t scale. Service-to-service authorization missing or hardcoded. Multi-datacenter networking is complex challenge. External services (RDS, SaaS) outside mesh.

HashiCorp Consul is service networking platform for distributed systems. Service discovery - automatic registration and health checking. Service mesh with mTLS - encrypted by default. Intentions - declarative authorization. Multi-datacenter native.

How does it work?

Service Discovery

Automatic networking:

• Service registration
• Health checking
• DNS and HTTP API
• KV store
• Dynamic updates

Service Mesh

Zero Trust networking:

• mTLS encryption
• Sidecar proxy (Envoy)
• Transparent proxy
• Traffic control
• L7 routing

Intentions

Service authorization:

• Allow/deny policies
• Declarative configuration
• Namespace isolation
• Identity-based
• Auditable

Main features

Service Discovery

• Automatic registration
• Health checking
• DNS interface
• HTTP API
• Multi-datacenter

Service Mesh

• mTLS everywhere
• Envoy sidecar
• Transparent proxy mode
• Traffic splitting
• Failover

Traffic Management

• Load balancing
• Canary deployments
• Blue-green routing
• Circuit breakers
• Rate limiting

External Services

• ESM (External Service Monitor)
• SaaS integration
• RDS, Azure DB discovery
• Health monitoring
• Mesh integration

Architecture

┌─────────────────────────────────────────┐
│            Consul Servers               │
│         (Control Plane)                 │
└─────────────────┬───────────────────────┘
                  │
    ┌─────────────┼─────────────┐
    │             │             │
┌───┴───┐    ┌────┴───┐   ┌─────┴───┐
│ App A │    │ App B  │   │ App C   │
│+Envoy │←──→│+Envoy  │←──→│+Envoy  │
│(mTLS) │    │(mTLS)  │   │(mTLS)   │
└───────┘    └────────┘   └─────────┘

Deployment Options

Model	Use Case	Features
OSS	Development, small prod	Core features
Enterprise	Production	Namespaces, audit, admin partitions
HCP Consul	Managed	Zero ops, global scale

Multi-Runtime Support

• Kubernetes - native integration
• VMs - traditional deployments
• Nomad - HashiCorp orchestrator
• ECS/EKS - AWS containers
• Bare metal - any Linux

For whom?

• Platform teams building service mesh
• DevOps deploying microservices
• Security teams seeking Zero Trust networking
• Multi-cloud/hybrid environments

Benefits

For Platform: Unified service networking, automatic discovery, traffic control

For Security: mTLS everywhere, service authorization, audit logging

For Operations: Multi-datacenter, observability integration, simplified networking

Specifications

Proxy	Envoy sidecar
Encryption	mTLS (automatic)
Discovery	DNS, HTTP API
Scale	Thousands of services

FAQ

What is service mesh? Infrastructure layer handling service-to-service communication. Encryption, routing, observability.

Is mTLS automatic? Yes. Consul automatically generates certificates and rotates them. Zero config for encryption.

How does transparent proxy work? Application doesn’t know about mesh. Consul redirects traffic through Envoy without code changes.

What are intentions? Service-to-service authorization rules. “Service A may talk to Service B”. Declarative and auditable.

Does it support multi-datacenter? Yes. Native federation. WAN gossip for cross-DC discovery and failover.

How does it integrate with Kubernetes? Connect injector for sidecar injection. Consul as service registry for K8s services.

What about external services (RDS, SaaS)? External Service Monitor (ESM). Consul can monitor and include external services in mesh.

Do I need Envoy? Consul uses Envoy as data plane. Automatic deployment and configuration.

What does observability look like? Metrics export to Prometheus, traces to Jaeger/Zipkin. Consul UI dashboard.

What does support look like? HashiCorp/IBM support. nFlo offers Consul deployment, migration and mesh architecture design.