Frequently Asked Questions

General Questions

Why LavinMQ?

Handle LavinMQ

Integration and availability

Security

General Questions

What is LavinMQ?

LavinMQ is a high-performance messaging queuing software built upon the AMQP 0.9.1 protocol. It gives applications a common platform to send and receive messages. LavinMQ comes with low RAM requirements and the ability to handle extremely long queues and many connections. LavinMQ is built to include popular characteristics from other message brokers, combining the best from RabbitMQ and Kafka, the ease of use of AMQP, and the freedom to re-consuming messages like Kafka with a persistent exchange and replayable/rewindable queues.

Messages can be sent across languages, platforms, and OS, which decouples processes from each other and creates a highly scalable system. All AMQP client libraries work with LavinMQ and there are AMQP client libraries for almost every platform on the market including Ruby, Node.js, Java, Python, PHP and Crystal.

What is a Message?

A message is the data transported between the publisher and the consumer; essentially a message is a byte array with headers on top.

Read more about messages.

What is a Message Queue?

A message queue enables independent, unrelated applications to exchange information asynchronously. Message queues store packets of information created by other applications for yet another set of applications to consume. In doing so, a message queue prevents data loss and enables efficient, continuous system function even in the case of a network or another failure.

What is a Message Broker?

LavinMQ is a message queuing server, also known as a message broker. A message broker’s purpose is to handle incoming messages from applications. The message broker routes the messages within the broker to one or many destinations and stores them in a queue until they are consumed by a consumer.

What is AMQP?

LavinMQ implements an extension of the open standard AMQP 0.9.1 specification. It is the protocol used as the basis for a set of standards controlling the entire message passing process. LavinMQ implements the AMQP protocol, version 0.9.1.

As with other message queuing protocols, the defining features of AMQP are message orientation and queuing. Routing is another feature and is basically the process by which an exchange decides which queues to place your message on. Messages in LavinMQ are routed from the exchange to the queue depending on exchange types and keys. Reliability and security are other important features of AMQP

All AMQP client libraries work with LavinMQ and there are AMQP client libraries for almost every platform out there, including Ruby, Node.js, Java, Python, Crystal, and PHP.

What is a Connection?

A connection is a TCP connection between your application and the LavinMQ broker.

Read more about AMQP Connections and Channels

What is a Channel?

A channel is a virtual connection inside a (TCP) connection. A channel is used to send AMQP commands to the broker. Publishing or consuming messages or subscribing to a queue are all done over a channel.

Read more about AMQP Connections and Channels

Why LavinMQ?

How can we use LavinMQ?

Imagine that you have a web service that receives many requests every second, where no request should get lost and the request processing is time-consuming. Further, imagine that your web service always has to be available and ready to receive a new request instead of being locked by the processing of previously received requests.

In this case, placing a queue between the web service and the processing service is the best way to achieve a successful outcome. The two processes will be decoupled and do not need to wait for each other. If you have a lot of requests coming in a short amount of time, the processing system will be able to process them all. The queue will persist requests if their number becomes really huge.

Then imagine that your business and your workload is growing and you need to scale up your system. All that is needed to be done now is to add more workers to work off the queues faster.

In addition to providing a buffer between a web service and another processing service, message queues can be used for more advanced scenarios. LavinMQ can be configured to route and distribute messages according to different rules and different processes. Messages can be added to different queues depending on how the messages should be handled. The processing systems can then process them at their leisure.

Use LavinMQ when you want a fast and easy to set up a message broker with routing options. Use LavinMQ when you need support for long queues and many connections. This blog describes when to use LavinMQ.

Handle LavinMQ

How can I separate applications within the same broker?

Virtual Hosts (vhosts) make it possible to separate applications on one broker. You can isolate users, exchanges, queues, etc. to one specific vhost. You can separate environments, e.g. production to one vhost and staging to another vhost, within the same broker instead of setting up multiple brokers.

vhosts can be added to all dedicated instances. The downside of using a single instance is that there’s no resource isolation between virtual hosts.

Read more about AMQP vhosts

Integration and availability

Do I enable any plugins in LavinMQ?

No, all features are enabled by default.

Which protocols does LavinMQ support?

LavinMQ supports AMQP version 0.9.1 and MQTT.

What is lavinmqctl?

Yes, it is possible to use lavinmqctl directly to your LavinMQ running on CloudAMQP. The CLI tool accepts a full URI, including username and password under the –host flag. Use the same username and password as you use for your AMQP connections.

Read more about LavinMQ Command Line Interface.

Is it possible to move messages from one server to another?

LavinMQ provides two types of federation: exchange and queue federation. A federated exchange can route messages published to an upstream server to a local queue. A federated queue allows a local consumer to receive messages from an upstream queue.

Security

Does LavinMQ support TLS/SSL?

LavinMQ does support TLS (SSL). In most clients it is easy to use TLS, just replace amqp:// with amqps:// in the URL.

Note: TLS will only secure messages during the transport. What we recommend for highly sensitive information (HIPAA, PCI, etc.) is encrypting the message bodies on your side and that you have a shared key between the publishers and the consumers.

Can I send encrypted message bodies sent over AMQP?

AMQP’s messages are just byte arrays, you can send anything, encrypted or not.