Skip to main content


Part 1: Installing Unravel Server on CDH+CM

This topic explains how to deploy Unravel Server on Cloudera Distribution of Hadoop (CDH). Your CDH environment must be running Cloudera Manager (CM).


If you have not already done so, confirm your cluster meets Unravel's CDH​ compatibility matrix hosting requirements.

1. Configure the host

Use Cloudera Manager to allocate a cluster gateway/edge/client host with HDFS access, and create a gateway configuration for the host. The gateway configuration must have client roles for HDFS, YARN, Spark, Hive, and optionally, Spark2.

3. Install Unravel Server
  1. Download the Unravel Server RPM.

  2. Ensure that the host machine's local disks have the minimum space required.

    Unravel Server uses two separate disks: one for binaries (/usr/local/unravel) and one for data (/srv/unravel). The separate disk /srv/unravel is beneficial for performance. If either of the disks do not have the minimum space required, create symbolic links for them to another disk drive.


    To check the space on a volume use the df command. For example,

    df -h /srv
  3. Install the Unravel Server RPM.

    sudo rpm -Uvh unravel-version.rpm
5. Configure Unravel Server with basic options
  1. (Optional) Enable additional daemons for high-volume workloads.

  2. In /usr/local/unravel/etc/, set general properties for Unravel Server.

  3. Point Unravel Server to logs on HDFS.

    Unravel collects HDFS logs for analysis. To point Unravel Server to these logs, set the following properties in /usr/local/unravel/etc/

    For example,


    To confirm that you have the right path, use the hdfs dfs -ls command. For example,

    hdfs dfs -ls /user/history/done
    hdfs dfs -ls /tmp/logs
  4. If Kerberos is enabled, create or identify a principal and keytab for Unravel daemons to use for access to HDFS and the REST API.

  5. If Sentry is enabled:

    1. Create your own alternate principal with narrow privileges and HDFS access permissions.

    2. Verify that the user running the Unravel daemon /etc/unravel_ctl has the permissions shown in the table below.






      Your alt principal


      Spark event log


      Your alt principal


      Spark2 event log (if Spark2 is installed)


      Your alt principal


      MapReduce logs


      Your alt principal


      YARN aggregation folder


      Your alt principal


      Obtain table partition sizes with "stat" only

  6. If you are using a virus scanner

    We recommend you disable your virus scanner from scanning the elasticsearch directories which are located under /srv/unravel.

6. Change the run-as user and group for Unravel daemons

Unravel daemons run under the local user unravel by default. However, if you have Kerberos or Sentry enabled, or a non-Kerberos cluster with simple Unix security, or a different username for the Unravel user, or a non-local user such as an LDAP user, run script to change the Unix owner and group of the Unravel daemons.

8. Start Unravel services

Run the following command to start all Unravel services:

sudo /etc/init.d/ start
sleep 60

This completes the basic/core configuration.

9. Log into Unravel UI
  1. Find the hostname of Unravel Server.

    echo "http://$(hostname -f):3000/"

    If you're using an SSH tunnel or HTTP proxy, you might need to make adjustments.

  2. Using a supported web browser, (see ​Unravel's ​​Databricks​ compatibility matrix), navigate to http://unravel-host:3000 and log in with username admin with password unraveldata.


    Unravel UI displays collected data.