Denodo Replicator provides an interface for import/export operations between several Denodo Platform servers so that you can synchronize them. This document introduces the reader to the tool.
This document is aimed at system administrators that require performing synchronization operations between different servers of Denodo Platform.
This document describes:
This software requires, at least, JRE1.7 installed. The environment variable JAVA_HOME must be pointing to the folder containing the JRE installation.
As the import/export functionalities make use of several files in your Denodo Platform installation, you will need to have the environment variable DENODO_HOME set and pointing to your Denodo Platform installation folder.
This software is distributed in a zip file. To install it, extract its content to a folder in the file system.
To launch the application, execute one of the scripts included in the bin folder:
These scripts use the JAVA_OPTS environment variable to configure the JVM. If it does not exist, the variable will be set to -Xmx1024m, usually enough for the import/export features. Please, make sure you use enough memory for the import/export processes to work.
Once the tool is launched, the initial empty screen will be displayed. Below there is an image.
Denodo Replicator can connect with a Denodo server that has SSL enabled.
Some configuration might be needed at the launcher scripts:
-Djavax.net.ssl.trustStore=<path_to_truststore>.
Note that, depending on the operating system you are using, you might need to modify denodo-replicator.bat or denodo-replicator.sh.
You could adapt your denodo-replicator.bat script by replacing this line:
%JAVA_BIN% %JAVA_OPTS% -classpath "%REPLICATOR_CLASSPATH%" com.denodo.connect.monitoring.replicator.ReplicatorTool %* |
with:
%JAVA_BIN% %JAVA_OPTS% -Djavax.net.ssl.trustStore= "DENODO_HOME/jre/lib/security/cacerts" -classpath "%REPLICATOR_CLASSPATH%" com.denodo.connect.monitoring.replicator.ReplicatorTool %* |
In addition, all the certificates of the servers secured with SSL taking part in Replicator’s synchronization operations have to be imported into the java cacerts store file of the installation of the platform pointed by the DENODO_HOME environment variable.
There is al alternative option instead of modifying the execution scripts: to modify the JAVA_HOME environment variable. Setting the virtual machine of the DENODO_HOME installation as JAVA_HOME. If you execute Denodo Replicator in a Windows system, you can do this:
> set JAVA_HOME=%DENODO_HOME%\jre > denodo_replicator.bat |
IMPORTANT: The Denodo Platform version and patch of the servers involved in the process should be the same in order for the import/export to work. Please, prior to synchronizing using Replicator make sure:
If the previous requirements are not met, please, perform the synchronization processes manually by using the import/export scripts as explained at the “Virtual DataPort Administration Guide”.
The Denodo Replicator has three main areas: the menu bar, the side tree, and the workspace.
It has the following menu entries:
It shows a list of the servers and environments that have been added to the tool.
The following options are available for each type of element and they are accessible using the right click popup menu.
The right click menu options for each server are:
The right click menu options for each environment are:
Edit: opens the edit environment dialog in the workspace area
Delete: removes the environment from the list. A confirmation popup will be displayed prior to this operation.
Synchronize Environment: imports metadata from the Master node to the other servers in the environment. When this action is used, a pop-up window appears, where you can choose the options of the synchronization:
For each server that belongs to the environment, these are the right click menu options:
When this action is used, a pop-up window appears, where you can choose the options of the import. These options are the same that in the option Synchronice environment, you can learn more about these options above these lines.
It is the main screen of the tool and it is where all the dialogs are displayed.
This section provides a detailed overview on the servers section of the tool.
Before synchronizing any set of servers, those servers must be added to Denodo Replicator. The screen where a new server is defined can be accessed in three ways:
The New Server form looks like this:
The following parameters must be filled:
All the parameters are required. Once the form is filled, click Ok to create the server, or Cancel to leave the tool with no changes.
An existing server can be edited by clicking on the Edit option of the popup menu of the server node. The form is identical to the New Server form, but the inputs are filled in with the current parameters.
Once the modifications are done, click Ok to modify the server, or Cancel to leave the server with no changes.
This section provides a detailed overview on the environments section of the tool. An environment is just a set of servers that can be synchronized between them: import master server metadata into every other server in the environment.
The screen for defining a new environment can be accessed in three ways:
Below there is a screenshot of the New Environment form, displayed in the workspace area:
The following parameters must be filled:
Name is required and, at least, one server must be selected. Once the form is filled, click Ok to create the environment, or Cancel to leave the dialog, with no changes.
An existing environment can be edited by clicking on the Edit option of the popup menu of the environment. The form is almost identical to the New Environment one, but the inputs are filled with the current parameters and there is one additional button to clear the master node of the environment.
In case you wish to clear the master node, click Clear Master Node. Otherwise, once the modifications are done, click Ok to modify the environment, or Cancel to leave the environment with no changes.
Once you have an environment defined and its master node configured, you can synchronize that environment by right clicking on the environment name and selecting the option Synchronize Environment.
The synchronization operation consists of exporting the metadata of the master node to a single file for re-creating the same metadata in the rest of the servers of the environment.
The steps performed by the synchronization process are:
An exception at this point will abort the whole process and an error icon will appear next to the master node name.
If an exception occurs during this step, the synchronization of this server will stop although, the other servers will not be affected and the whole process will go on. In this case the progress bar will turn red to let you know there has been an exception.
Below there is an image of the synchronization process once finished:
The window above contains three main areas:
During the execution of the synchronization process there can be both exceptions and errors. There is an important difference between them.
If an exception occurs, the progress bar will turn red and the task throwing the exception will be aborted whereas, if there is an error, the task execution will go on and a warning icon will appear on the left of the window so that you know at what point the error happened and you can go to that part of the log in the window.
An error can be just a problem with the execution of any VQL sentence contained in the master node export when imported into a server whereas an exception may be a connection problem to a server node.
The progress bar at the top of the synchronization window will let you know when the process finishes. If any exceptions arise, the bar will turn red.
All the different tasks of the current synchronization process will be displayed here. Each task contains an icon at the right that lets you know its status:
Waiting status. The task is waiting to be executed |
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Processing. The task is being executed |
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Ok. The task has finished correctly |
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Warning. The task has finished but it has errors. You should check the log of the task |
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Error. The task has not finished due to an exception. You should check the log of the task. In this case, the progress bar will turn red as a task execution has been aborted |
This window displays the logging information of the tasks performed. Any error messages will be displayed in red so that they can be easily located. Note that every task starts with a bold message, i.e. “Synchronizing serverA with master...”, “Saving serverB backup...”, etc.
Symptom
Denodo Replicator tries to connect to a VDP server and shows the following error: “sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target”
Resolution
VDP Server has SSL enabled, so it is necessary to specify the location of the trust store in the launcher script of the Replicator.
In order to enable SSL connections between VDP Server and the Replicator see section Enable SSL connections.
Symptom
Denodo Replicator tries to make ping in a server and shows the following error:
Resolution
VDP Server and Denodo Replicator are not compatible. You should update the version of VDP server or the version of Denodo Replicator.