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.
If you already have Zero Downtime Migration software installed on a host, you should always make sure it is the latest available release. Zero Downtime Migration software updates give you the latest features and fixes while retaining existing job information, metadata, and log files. Always check the version and determine if it is the latest by comparing it with what's available on the downloads page.
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.
2.1 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 pre-installation tasks before installing Zero Downtime Migration software on it.
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The Zero Downtime Migration service host should be a dedicated system, but it can be shared for other purposes.
However, if the Zero Downtime Migration service is installed on the same host where RHP server is deployed, see Running RHP and Zero Downtime Migration Service on the Same Host for more info.
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Zero Downtime Migration software requires a standalone Linux host running on any one of the following platforms:
Oracle Linux 7, Oracle Linux 8, or Red Hat Enterprise Linux 8.
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The Zero Downtime Migration service host must be able to connect to the source and the target database servers.
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Ensure that the Linux host has 100 GB of free storage space.
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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
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Verify that the
glibc-devel
andexpect
packages are installed.For Oracle Linux 8, or Red Hat Enterprise Linux 8 installations with Base Environment "Minimal Install" you also need to install the packagesunzip libaio oraclelinux-developer-release-el7 libnsl
andncurses-compat-libs
.- Minimum OS version Oracle Linux 7 - Ensure Packages 'glibc-devel' and 'expect' are installed - For higher versions such as Oracle Linux 8: - Ensure Packages 'libnsl' and 'ncurses-compat-libs' are also installed - glibc-devel' and 'expect are a must for either versions - unzip libaio oraclelinux-developer-release-el7 libnsl and ncurses-compat-libs are required for Oracle Linux 8 and Red Hat Enterprise Linux 8
-
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 withping
. -
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
2.3 Installing Zero Downtime Migration on VM in Oracle Cloud Infrastructure
You can install ZDM on a VM in OCI by performing the following steps:
2.4 Installing Zero Downtime Migration on Red Hat Enterprise Linux 8 in an Oracle Cloud Infrastructure Instance
You can install ZDM on a Red Hat Enterprise Linux 8 in an OCI instance by performing the following steps:
2.4.1 To install Zero Downtime Migration on Red Hat Enterprise Linux 8
- Obtain Red Hat Enterprise Linux 8.8 KVM Guest Image from here.
- Upload the image to a new OCI bucket.
- Import the image as custom image.
- Create an instance from the image.
- Generate new SSH keys.
- Connect to the RHEL8 OCI instance.