Softwr

Cloud · head to head

HAProxy vs Eclipse Mosquitto

HAProxy logo

HAProxy

Cloud

High-performance TCP and HTTP load balancer

From
Free
Rated
-
Full reviewWebsite
Eclipse Mosquitto logo

Eclipse Mosquitto

Networking

Small, EPL-licensed MQTT broker that runs on hardware other brokers cannot

From
Free
Rated
-
Full reviewWebsite

The short version

  • Each has a real cost: HAProxy configuration syntax is dense and unforgiving, with a steep initial learning curve; Eclipse Mosquitto there is no clustering: Mosquitto is a single process, so high availability means building your own failover and accepting session loss on switchover.
  • They diverge on capability: HAProxy covers High throughput, Eclipse Mosquitto covers MQTT 5.0 support.
  • Prices and features above were last checked on 31 August 2026.

Where they differ

Only the attributes on which HAProxy and Eclipse Mosquitto actually diverge.

Attributes where HAProxy and Eclipse Mosquitto differ
AttributeHAProxyEclipse Mosquitto
PlatformsLinux, Docker, Kubernetes, Self-hostedLinux, Windows, macOS, Docker
CategoryCloudNetworking

Identical on both: starting price (Free), pricing model (Open source, no licence fee), free tier (Yes), user rating (Not yet rated).

What each one covers

Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.

Only in HAProxy

  • High throughput
  • Layer 4 and 7
  • Health checking
  • Rate limiting and ACLs

Only in Eclipse Mosquitto

  • MQTT 5.0 support
  • Very small footprint
  • Bridging
  • WebSockets listener
  • Command line clients
  • Dynamic security plugin

What people use each for

The jobs each tool is most often brought in to do.

HAProxy

  • Load balancing at traffic levels where proxy efficiency shows up in the hardware billnot Eclipse Mosquitto
  • Precise traffic control — rate limits, sticky sessions, complex routing rulesnot Eclipse Mosquitto
  • TCP load balancing for databases and non-HTTP servicesnot Eclipse Mosquitto

Eclipse Mosquitto

  • A home or building automation stack where the broker must run on the same small computer as everything elsenot HAProxy
  • An industrial gateway that buffers local telemetry and bridges selected topics to a cloud brokernot HAProxy
  • Local development and testing of MQTT clients without provisioning a cloud IoT servicenot HAProxy
  • An air-gapped deployment where a broker with no licence server and no phone-home behaviour is a requirementnot HAProxy

Where each one falls short

Documented limitations, not opinions. Every one is a constraint you would hit in normal use.

HAProxy

  • Configuration syntax is dense and unforgiving, with a steep initial learning curve
  • No automatic certificate management, unlike newer servers that treat it as default behaviour
  • The built-in stats page is basic, so real observability needs exporters and dashboards
  • A dedicated load balancer is more machinery than small deployments need

Eclipse Mosquitto

  • There is no clustering: Mosquitto is a single process, so high availability means building your own failover and accepting session loss on switchover.
  • Persistence is a local file rather than a replicated store, so a disk failure or an unclean shutdown can lose retained messages and queued QoS traffic.
  • Practical capacity is a few thousand concurrent clients on typical hardware, so a growing device fleet eventually forces a migration to a clustered broker.
  • The Eclipse Public Licence is weak copyleft rather than permissive, which some legal teams treat as a blocker when embedding the broker in a shipped commercial product.
  • There is no commercial support to buy from the project, so production incidents rely on community mailing lists or on paying a third party who happens to know the codebase.

Pricing, plan by plan

HAProxy

Free
  • HAProxyFree
    • Full functionality
    • No usage limits
    • Community support

Eclipse Mosquitto

Free
  • Eclipse MosquittoFree
    • Eclipse Public License 2.0 with Eclipse Distribution Licence
    • MQTT 5.0, 3.1.1 and 3.1
    • No client or message limits beyond your hardware

Which should you pick?

Choose HAProxy if

  • You need high throughput.
  • You want to start without paying.
  • You work on Linux, Docker, Kubernetes, Self-hosted.
  • You also want layer 4 and 7.
HAProxy review

Choose Eclipse Mosquitto if

  • You need mqtt 5.0 support.
  • You want to start without paying.
  • You work on Linux, Windows, macOS, Docker.
  • You also want very small footprint.
Eclipse Mosquitto review

Questions people ask

Is HAProxy or Eclipse Mosquitto better?
Neither clearly leads. HAProxy starts at Free and Eclipse Mosquitto at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, HAProxy or Eclipse Mosquitto?
HAProxy starts at Free and Eclipse Mosquitto at Free.
Does HAProxy or Eclipse Mosquitto run on more platforms?
HAProxy runs on Linux, Docker, Kubernetes, Self-hosted. Eclipse Mosquitto runs on Linux, Windows, macOS, Docker.
Can I use HAProxy for free?
Both have a free tier, so you can try either at no cost before committing.
What is HAProxy best used for?
HAProxy is most often used for load balancing at traffic levels where proxy efficiency shows up in the hardware bill, precise traffic control — rate limits, sticky sessions, complex routing rules, tcp load balancing for databases and non-http services. Of those, load balancing at traffic levels where proxy efficiency shows up in the hardware bill and precise traffic control — rate limits, sticky sessions, complex routing rules are not what Eclipse Mosquitto is typically brought in for.
What can HAProxy do that Eclipse Mosquitto cannot?
HAProxy covers High throughput, Layer 4 and 7, Health checking, Rate limiting and ACLs. Eclipse Mosquitto covers MQTT 5.0 support, Very small footprint, Bridging, WebSockets listener.

Answered from the vendors’ own pages

HAProxy: Is HAProxy free?

Yes, the community version is open source. HAProxy Technologies sells HAProxy Enterprise separately.

Eclipse Mosquitto: Can Mosquitto be clustered?

No. It is a single process. High availability requires an external failover arrangement you build yourself.

HAProxy: HAProxy or Nginx?

HAProxy is a specialist load balancer with deeper balancing and health-check features. Nginx also serves static content and is more approachable, which is why it is more common as a general web server.

Eclipse Mosquitto: What licence is it?

Eclipse Public License 2.0 alongside the Eclipse Distribution License, a weak copyleft rather than a permissive licence.

HAProxy: Does HAProxy handle TLS certificates automatically?

No. Certificate issuance and renewal are external, unlike Caddy where it is automatic.

Eclipse Mosquitto: How many clients can it handle?

A few thousand concurrent connections on ordinary hardware; beyond that, use a clustered broker.

Eclipse Mosquitto: Does it support MQTT 5?

Yes, along with 3.1.1 and 3.1.

Share

Related pages

More on HAProxy

More on Eclipse Mosquitto

Keep looking

Other head to heads