Why do they indicate exchange in the logstash config when linking to the rabbitmq queue as a source of logs?

Question

RabbitMQ

I have logs in the rabbitmq queue.
I want to connect logstash with a log queue for further loading into elasticsearch.

There were some questions:

1. Where to place logstash'a config for input/output description?
Different sources have different information.
I try to write the config here: /etc/logstash/conf.d/rabbitmq.conf
I created the config file myself. Will the system find it on its own?
Or do you need to connect somewhere?

2. Do I need to describe output for elasticserach by default? Or will they go there by default from logstash?

3. The most important question:

I often see the following in various examples of logstash + rabbitmq configs:

input {
  rabbitmq {
    host => my_host_name
    port => 5672
    vhost => /
    user => guest
    password => guest
    queue => my_queue_name
    exchange => logs
  }
}

namely, along with the name of the queue indicate *exchange* ? for what ? And there were even cases when it was purely exchange, even without the name of the queue?

Answer 1

I try to write the config here: /etc/logstash/conf.d/rabbitmq.conf
I created the config file myself. Will the system find it on its own?

yes, this is a very popular and convenient method of adding configs - the main config contains 'include conf.d/*.conf' - look in /etc/logstash/logstash.conf.

Is it necessary to describe output for elasticserach by default? Or will they go there by default from logstash?

need.

Answer 2

I will answer only for rabbitmq. In the concept of this broker, it is necessary to send a message to exchange, since it is a message router. It is technically possible to send to the queue, but you should not do this because then there will be difficulties if necessary to reconfigure