2 Setting Up Zero Downtime Migration Software

When you install Zero Downtime Migration software, read this section carefully as there may have been changes since the last time you performed an installation.

The Zero Downtime Migration software kit supports both physical and logical migrations. You only need to install one kit to get all of the functionality.

Always see the Zero Downtime Migration Release Notes for the latest information about known issues. Also, see the README file included with the downloaded Zero Downtime Migration software for any additional information about software installation and updates.

For information about updating existing software to the latest release, removing the software, and starting and stopping the Zero Downtime Migration service, see Managing the Zero Downtime Migration Service.

Prepare a Host for Zero Downtime Migration Software Installation

If a host has not had Zero Downtime Migration software installed on it previously, verify that it complies with the requirements and perform any pre-installation tasks, then download and install the software. Once the software is installed, the host is referred to as the Zero Downtime Migration service host.

Provision a host with the following prerequisites and complete the following preinstallation tasks before installing Zero Downtime Migration software on it.

  • The Zero Downtime Migration service host should be a dedicated system, but it can be shared for other purposes; however, the Zero Downtime Migration service host should not have Oracle Grid Infrastructure running on it.

  • Zero Downtime Migration software requires a standalone Linux host running Oracle Linux 7.

  • The Zero Downtime Migration service host must be able to connect to the source and the target database servers.

  • Ensure that the Linux host has 100 GB of free storage space.

  • You may use an existing user, or, on the Zero Downtime Migration service host, as root user, create a zdm group and add zdmuser user to the group.

    For example,

    root> groupadd zdm
    root> useradd –g zdm zdmuser
  • Verify that the glibc-devel and expect packages are installed.

    For Oracle Linux 7 installations with Base Environment "Minimal Install" you also need to install the packages unzip libaio oraclelinux-developer-release-el7.

  • Verify that the /etc/hosts entry for the host name and IP address are configured as expected, so that the host selected for Zero Downtime Migration software installation resolves to the correct IP address and the IP address is reachable with ping.

  • During the installation, the script might report any missing packages and instructions for setting appropriate values for kernel parameters. Be sure to install the missing packages and set the kernel parameters before the Zero Downtime Migration software installation.

  • Optionally, set a ZDM_HOME environment variable to the absolute path of the directory where the Zero Downtime Migration software will be installed. All of the examples in this document use $ZDM_HOME.

    zdmuser> export ZDM_HOME=absolute_path_to_zdm_home

Install Zero Downtime Migration Software

All commands are run as zdmuser.

  1. Download the Zero Downtime Migration software kit from https://www.oracle.com/database/technologies/rac/zdm-downloads.html to the Zero Downtime Migration service host.
  2. Install the Zero Downtime Migration software as a non-root user.

    In this example the installation user is zdmuser.

    1. Change to the directory to where Zero Downtime Migration software is downloaded and unzip the software.
      zdmuser> cd zdm_download_directory
      zdmuser> unzip zdmversion.zip 
    2. Run the Zero Downtime Migration installation script.
      zdmuser>./zdminstall.sh setup oraclehome=zdm_oracle_home oraclebase=zdm_base_directory
              ziploc=zdm_software_location –zdm
      • zmdinstall.sh is the installation script
      • oraclehome is the absolute path to the Oracle Home directory where the Zero Downtime Migration software will be installed.
      • oraclebase is the absolute path to the base directory where all of the Zero Downtime Migration configuration files, logs, and other artifacts are stored
      • ziploc is the location of the compressed software file (zip) included in the Zero Downtime Migration kit

      For example,

      zdmuser>./zdminstall.sh setup oraclehome=/u01/app/zdmhome
              oraclebase=/u01/app/zdmbase ziploc=/u01/app/oracle/zdm/shiphome/zdm_home.zip

    Hereafter, the oraclehome value is referred to as ZDM_HOME, and the oraclebase value is referred to as ZDM_BASE.

    Ignore the following messages which are displayed on the terminal at the end of installation. There is no need to run these scripts.

    As a root user, execute the following script(s):
            1. $ZDM_HOME/inventory/orainstRoot.sh
            2. $ZDM_HOME/root.sh
  3. Start the Zero Downtime Migration service as user zdmuser.
    zdmuser> $ZDM_HOME/bin/zdmservice start

    You must start zdmservice before you can migrate your databases using Zero Downtime Migration.

    If you must stop the Zero Downtime Migration service, run the following command.

    zdmuser> $ZDM_HOME/bin/zdmservice stop
  4. Verify that the Zero Downtime Migration service installation is successful.
    When you run the following command, the output should be similar to that shown here.
    zdmuser> $ZDM_HOME/bin/zdmservice status
            Service Status
    Running:       true
    Tranferport:   5000-7000
    Conn String:   jdbc:mysql://localhost:8897/
    RMI port:      8895
    HTTP port:     8896
    Wallet path:   /u01/app/zdmbase/crsdata/fopds/security
  5. If necessary, change the default MySQL port.

    Zero Downtime Migration uses MySQL internally, configuring it by default on port 8897, as shown in the above zdmservice status example output. If you want to change this port number, see Setting the MySQL Port.