1.10

How to use Cerebro on DC/OS

Cerebro is a web admin tool for managing Elastic clusters.

• Estimated time for completion: 5 minutes
• Target audience: Elastic clusters administrators.
• Scope: Install and use Cerebro.

Table of Contents:

• Prerequisites
• Install Cerebro
• Cerebro configuration
• Using Cerebro
• Uninstall Elasticsearch

Prerequisites

• A running DC/OS 1.10 cluster with least one agent with 0.5 CPU, 1.5 GB RAM and 1 GB of disk space available.

Install Cerebro

To install Cerebro, you can either use DC/OS CLI:

$ dcos package install cerebro

optionally you can provide extra options:

$ dcos package install cerebro --options=cerebro.json

where cerebro.json would contain advanced configuration, with e.g. predefined Elastic clusters:

{
  "service": {
    "name": "cerebro",
    "user": "nobody",
    "cpus": 0.5,
    "mem": 1180,
    "instances": 1,
    "heap": 1024
  },
  "elastic": {
    "cluster_1": "http://master.es01.l4lb.thisdcos.directory:9200",
    "cluster_2": "http://master.es02.l4lb.thisdcos.directory:9200"
  },
  "authentication": {
    "type": "none",
  }
}

Or install from Cerebro from DC/OS Catalog (Universe):

If you hit the "Configure" button you can adjust Cerebro's configuration the same way as with CLI. You can define up to 5 Elastic clusters (later you can define even more):

All configuration options can be altered later, thus you don't have to worry about this now.

After pressing "Deploy" button, you should see the Cerebro service running via the Services tab of the DC/OS UI:

Using Cerebro

We can use the DC/OS Admin Router to provide access to the Cerebro UI: use the URL http://$DCOS_DASHBOARD/service/cerebro/ and replace $DCOS_DASHBOARD with the URL of your DC/OS UI:

Optionally you can access Cerebro via Marathon-LB, in that case it might be good idea to configure some authentication mechanism.

Cerebro configuration

Cerebro offers various configuration options exposed via ENV variables. You can pre-define several Elastic clusters by using ES_{n} variables. For each cluster you can define following:

• ES_1 URI to master node, e.g. http://localhost:9200
• ES_1_NAME human readable name of cluster (shown on Cerebro home page)
• ES_1_USER username
• ES_1_PASS password

LDAP authentication

In order to authenticate user via LDAP set CEREBRO_AUTH to ldap. And define following variables with approprite value:

• CEREBRO_LDAP_URL connection URL, e.g. ldap://host:port
• CEREBRO_LDAP_BASE LDAP base ou=active,ou=Employee
• CEREBRO_LDAP_METHOD simple
• CEREBRO_LDAP_DOMAIN example.com

Uninstall Cerebro

To uninstall Cerebro:

$ dcos package uninstall cerebro

Further resources

1. Cerebro project
2. Cerebro DC/OS packing