Uninstall Exasol

This section explains how to completely uninstall Exasol 8 from a host system.

Prerequisites

The user performing this procedure must either be root or a user with sudo access.

Procedure

The following examples use the c4 and confd_client command-line tools in a Linux terminal. For more information about these tools, see Exasol Deployment Tool (c4) and ConfD.

Step 1: Shut down the database

  1. Connect to EXAClusterOS (COS) using c4 connect -t <DEPLOYMENT>[.<NODE>]/cos. For example:

    c4 connect -t 1/cos

    For more information about how to use c4 connect, see How to use c4.

  2. If the database is running, stop it now using the ConfD job db_stop. For example:

    confd_client db_stop db_name: MY_DATABASE

  3. To verify that the database has stopped, use the ConfD job db_state. If the result is setup, the database is stopped. For example:

    confd_client db_state db_name: MY_DATABASE
    ...
    Result:
    'setup'

Step 2: Remove resources on the hosts

  1. To remove all resources that were created by c4 on the host system, run the following commands as sudo in a Linux terminal:

    If you are carrying out this operation as root, the sudo command should be omitted.

    # stop and disable the c4 services
    sudo systemctl stop c4_cloud_command
    sudo systemctl stop c4
    sudo systemctl disable c4
    sudo systemctl disable c4_cloud_command

    # remove the c4 services
    sudo rm /etc/systemd/system/c4_cloud_command.service
    sudo rm /etc/systemd/system/c4_cloud_command.env
    sudo rm /etc/systemd/system/c4.service
    sudo rm /etc/systemd/system/c4.env

    # remove directories and files created by c4
    sudo rm -r /var/lib/ccc
    sudo rm -r /usr/local/bin/c4
    sudo rm -r /var/log/ccc

    # unmount and remove the /x mount point
    sudo umount /x && sudo rm -rf /x

  2. Remove the .ccc directory in the home directory of the installation user:

    # if you are logged in as the installation user:
    rm -r ~/.ccc

    # if you are logged in as root:
    rm -r /home/<installation_user>/.ccc

  3. Repeat these steps on all hosts where you have installed Exasol 8.

After Exasol has been uninstalled, you can remove the installation user on the hosts if it is no longer needed. In that case you must be logged in as another user with sudo permissions or as root.