Run precheck

Precheck verifies if all the installation requirements of Unravel are fulfilled. You can check the prerequisites to ensure that all the requirements are in place before running precheck. After you download Unravel and deploy the Unravel binaries, you can run a precheck. In case any of the install requirements are not fulfilled, it is displayed in the Precheck output along with the required rectifications.

  1. Navigate to the installation directory.

  2. Run precheck as follows:

    <Unravel installation directory>/versions/<unravel-version>/setup --precheck

    There can be some service instances that you know can fail when you run the precheck before installation. In such cases to skip the checks, you can run precheck with additional arguments.

    For example, if you want to skip memory and Hadoop checks, run precheck with the following arguments:

    <Unravel installation directory>/versions/<unravel-version>/manager setup --filter-precheck ~hadoop,~mem_minimum

    Following is a sample output of running the precheck:

    2020-07-17 21:23:12 Sending logs to: /tmp/healthcheck-20200717212312-server.domain.com/healthcheck.log
    2020-07-17 21:23:13 Gathering information ................ Ok
    2020-07-17 21:23:36 Running checks .................... Ok
    Check uptime                  : OK
    Clock sync                    : OK
    CPU requirement               : OK, 8 cores
    Disk access                   : OK, /tmp/healthcheck/healthcheck/plugins/system is writable
    Disk freespace                : OK, precheck, found 152 GB.
    Kerberos tools                : OK
    Memory requirement            : OK, 98 GB
    Network ports                 : OK
    OS libraries                  : OK
    OS release                    : OK, centos 7.6
    OS settings                   : OK
    SELinux                       : OK
    Tmp noexec                    : OK
    Clients                       : OK
                                  - Found hadoop
                                  - Found hdfs
                                  - Found yarn
                                  - Found hive
                                  - Found beeline
    Distribution                  : OK, found CDH 6.1.1
    HDFS access                   : OK, /
    YARN access                   : OK
    Healthcheck bundle: /tmp/healthcheck-20200717212312-server.domain.com.tar.gz


In a multi-cluster environment, pre-checks must be run separately on the core node as well as on the edge node.