README: new behaviour described.

README.adoc

@@ -1,22 +1,47 @@
 = DNSBL exporter
 
-Provides an exporter to scan known DNSBL-provides for listing of target-IP.
+Provides an exporter to scan known DNSBL-providers for listing of target-IP.
 
 == Installation
 
 1. You have to installed `ruby` and `bundler`:
-
++
+[source,sh]
+----
 apt install ruby
 gem install bundler
+----
 
 2. Clone the repository to the destination, you want to have installed dnsbl_exporter.
 
-3. Start on boot:
+3. Copy `config.yml.example` to `config.yml` and change settings like resolver.
+
+4. Start on boot:
 +
+[source,sh]
+----
 useradd prometheus
 sudo -u prometheus bundle install
 erb dnsbl_exporter.service.erb > /etc/systemd/system/dnsbl_exporter.service
 systemctl daemon-reload
 systemctl enable --now dnsbl_exporter.service
+----
 
-4. In prometheus, define the target-IP as `target`.
+5. In prometheus, define the target-IP as `target`-param.
++
+[source,yaml]
+----
+- job_name: dnsbl4
+  static_configs:
+  - targets:
+    - '1.2.3.4'
+    - '1234::abcd'
+  relabel_configs:
+  - source_labels: [__address__]
+    target_label: __param_target
+    replacement: '${1}'
+  - source_labels: [__param_target]
+    target_label: instance
+  - target_label: __address__
+    replacement: {{prometheus_jobs_dnsbl_target}}
+----