Managing the Zero Downtime Migration Service

10.1 Starting and Stopping the Zero Downtime Migration Service

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

Start the Zero Downtime Migration service, zdmservice, as user zdmuser, with the following command.

zdmuser> $ZDM_HOME/bin/zdmservice start

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

zdmuser> $ZDM_HOME/bin/zdmservice stop

10.2 Checking Zero Downtime Migration Service Status

Check the status of the Zero Downtime Migration to see if it is running, and other service details.

To check the Zero Downtime Migration service status use the following command.

zdmuser> $ZDM_HOME/bin/zdmservice status
---------------------------------------
        Service Status
---------------------------------------
Running: false
 Tranferport:
 Conn String: jdbc:derby:/scratch/zdmuser/ZDM/base/derbyRepo;create=true
 Repo Path: /scratch/zdmuser/ZDM/base/derbyRepo
 RMI port: 8897
 HTTP port: 8898
 SSH port: 22
 Wallet path: /scratch/zdmuser/ZDM/base/crsdata/phoenix/security

10.3 Updating Zero Downtime Migration Software

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.

Before you begin the software update, review the following requirements.

Updating Zero Downtime Migration to the latest software can only be done from the latest Zero Downtime Migration kit. The current version is 26.1, and update can be done from version 21.5. Verify your software kit version using the following command:
```
zdmcli -build
full version: "26.1.0"
patch version: ""
label date: 260119
ZDM kit build date: Jan 28 2026 18:32:33 UTC
CPAT build version: 25.11.0
```
Verify that your existing Zero Downtime Migration software install location has at least 15GB free space.
Verify that you have enough space to back up the existing Zero Downtime Migration home (ZDM_HOME) and ZDM_BASE to the software download location.
Important: Run the update script from outside of the currently installed Zero Downtime Migration home.

Running the script from within a Zero Downtime Migration home results in home install and uninstall failures and leaves the service in an inconsistent state.
The path specified in ziploc should have read/write access for zdmuser.
All of the commands in the following procedure should be run as the existing Zero Downtime Migration software owner. For example, run as zdmuser in the examples that follow.

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.
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 
```
Run the zdminstall.sh script as the exiting Zero Downtime Migration home owner to update the software from the software download location.
```
zdmuser>./zdminstall.sh update oraclehome=existing_zdm_oracle_home
   ziploc=zdm_software_location
```
- zmdinstall.sh is the installation and update script
- oraclehome is the absolute path to the Oracle Home where the existing Zero Downtime Migration software is installed
- ziploc is the location of the compressed software file (zip) included in the Zero Downtime Migration kit
For example,
```
zdmuser>/u01/app/oracle/zdm/shiphome/update/zdminstall.sh update
     oraclehome=/u01/app/zdmhome
     ziploc=/u01/app/oracle/zdm/shiphome/update/zdm_home.zip
```
The update script does the following operations.
1. Backs up the existing Zero Downtime Migration home (ZDM_HOME) and ZDM_BASE into software download location
2. Stops the currently running Zero Downtime Migration service
3. Removes the currently installed Zero Downtime Migration home
4. Installs the new binaries in the Zero Downtime Migration home
5. Restores the configuration data.
The new Zero Downtime Migration home will retain all of the details of any migrations run with the previous Zero Downtime Migration home.
The Zero Downtime Migration service must be manually started after the upgrade. 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
```

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: false
 Tranferport:
 Conn String: jdbc:derby:/scratch/zdmuser/ZDM/base/derbyRepo;create=true
 Repo Path: /scratch/zdmuser/ZDM/base/derbyRepo
 RMI port: 8897
 HTTP port: 8898
 SSH port: 22
 Wallet path: /scratch/zdmuser/ZDM/base/crsdata/phoenix/security

10.4 Uninstalling Zero Downtime Migration Software

Remove Zero Downtime Migration software from the Zero Downtime Migration service host.

All commands are run as zdmuser.

Stop the Zero Downtime Migration service.
```
zdmuser> $ZDM_HOME/bin/zdmservice stop
```
Run the following command to uninstall the software.
```
zdmuser> $ZDM_HOME/bin/zdmservice deinstall
```

10.5 Performing a Silent Update or Deinstallation

You can skip the confirmation prompt during Zero Downtime Migration software update or deinstallation to ensure these operations run smoothly.

A -silent option is available for zdminstall.sh update or deinstall operations to avoid being asked for confirmation, as shown in the following examples.

Example of silent update:

zdmuser> cd zdm_download_directory
zdmuser> unzip zdmversion.zip 
...
zdmuser>./zdminstall.sh update -silent oraclehome=absolute_path_to_zdm_home  
ziploc=zdm_software_location

Example of silent deinstall:

zdmuser> $ZDM_HOME/bin/zdmservice deinstall -silent

10.6 Viewing the Cloud Premigration Advisor Tool Version

There are two ways to display the current version for the Cloud Premigration Advisor Tool (CPAT).

Run the Cloud Premigration Advisor Tool script with the --version option.
```
$ZDM_HOME/rhp/zdm/lib/cpat/premigration.sh --version
```
Run ZDMCLI with the -build option.
```
zdmuser> $ZDM_HOME/bin/zdmcli -build
```

10.7 Updating the Cloud Premigration Advisor Tool

Keep the Cloud Premigration Advisor Tool up to date to get the latest migration remedies, as well as any bug fixes in the tool.

Note:

Schedule Cloud Premigration Advisor Tool updates when no migrations are running.

Download the latest version of the tool from Cloud Premigration Advisor Tool (CPAT) Analyzes Databases for Suitability of Cloud Migration (Doc ID 2758371.1).
Check the version of the tool that is currently installed in your Zero Downtime Migration home.
```
./ZDM_home/rhp/zdm/lib/cpat/premigration.sh --version
```
Back up the currently installed tool by making a copy of the contents of directory $ZDM_HOME/rhp/zdm/lib/cpat.
Delete all of the files in directory $ZDM_HOME/rhp/zdm/lib/cpat.
Unzip the new Cloud Premigration Advisor Tool release file to $ZDM_HOME/rhp/zdm/lib/cpat.
If needed, change the permissions on the unzipped files to remove unauthorized access.
Verify that the new version of the tool is installed in your Zero Downtime Migration home.
```
./ZDM_home/rhp/zdm/lib/cpat/premigration.sh --version
```

10 Managing the Zero Downtime Migration Service