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Distributed Setup in Documentum III - Installing Remote Content File Server

December 21st, 2008

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In my last post, we discussed setting up of the primary site for a Single Repository Distributed Setup. In this post, we will look at installing the Remote Content File Server - the distributed storage component of a Distributed Setup. However, before we start the installation of the remote file server, we need to make a few changes to the configuration of primary content server that we installed in previous post. These settings include setting up of a distributed storage area and moving all system objects (dm_sysobject) to this distributed storage area.

Documentum abstracts all the details of distributed stores into what is known as a “Distributed Storage Area”. If you have worked with file stores and storage areas in Documentum Administrator (DA) before, you might already be aware of it. A distributed storage area is collection of filestores local or remote that are grouped together into a single logical unit. A filestore is just a drive or folder that has been allocated to Documentum to store documents and files. When you add filestores to a distributed storage area, all of them become part of a single storage area. When a user writes or saves a file to such a distributed storage area, content server determines the location and proximity of the user relative to the filestores in the distributed storage area and stores the file in a filestore that is nearest to the user. Internally, Content Server uses the concept of “Network Locations”, “Proximity Values” and “Remote file stores” to achieve this. All this is however, transparent, to the end user.

To prepare the primary content server for distributed setup, fire up your browser and point it to Documentum Administrator (DA) for the primary content Server. Login as either the installation owner or a superuser. On the navigation tree on left hand side, select “Storage” to bring up storage administrtion page. The screen should look the one below:

Before we setup a distributed storage area, we need to create a new local file store that will be part of this distributed area. The reason for creating a local filestore is two fold. One, it will be best to store all system files locally for obvious reasons. Therefore, after creating the new local file store we will move all dm_sysobjects to this filestore. And two, this filestore will also store any files that will be saved and accessed locally by users that are in proximity of this file store. You may also chose not to store any file on this file store. In this case, the final configuration will look slighlty different. Stay tuned for my next post for details. And yes, according to EMC’s distributed configuration guide, leaving the filestore_01 as it is, is a good choice for compatibility reasons.

To add a new local filestore, select “File Store” from File -> New menu, as shown below:

Enter a name for the file store e.g. filestore_02 and choose a path. Select “Select Server Path” option under “Location or Path” and choose a directory to store the content files in. This could be any location on SERVER’s hard drive where you’d like to store your content file e.g. “C:\Data”. Press “OK” when done.

Now that we’ve created a local filestore, it is time to create a distributed storage area. From File menu, select Distributed Store under New as shown below:

On the “New Distributed Store” webpage, specify a name for the distributed store e.g. distributed_store and select “Fetch Content Locally Only” checkbox. When you select this option on a give file/distributed store, content server only serves file that are on that files store. If a store has been identified as the nearest one for a particular user and the requested file is not present on that file store, content server WILL NOT fetch file directly from any other store. Instead, it will request the file from the other file store on behalf of this file store. The file in question will first be copied on to the local file store and only then will it be served to the user. This ensures that any subsequent fetches for this file from that file store’s region are fast.

Click on the “Components” tab or press the “Next” button.

Click the “Add” button and add the local file store you just created (filestore_02) by selecting filestore_02 (or whatever name you chose) and pressing the ” |>” button as shown below.

So that you screen looks like the one below.

Click OK and then click Finish to close the dialog box.

You should see you newly created file store and distributed storage area in the Storage administration screen now:

Once done, its now time to set the default storage area for all sysobjects to the newly created distributed storage area. To do this, select “Types” from navigation tree on left in DA and locate “dm_sysobject” on right frame.

Right click on dm_sysobject and select “Properties”. You should see a screen similar to the one below:

Under the “Info” tab, look for a drop down list called “Default Storage” and select the distributed storage area that you created above (distributed_store). Click “OK”

Now that you’ve told Content Sever to store all new dm_sysobjects in the distributed storage area, its time to move the ones that are already there to the distributed storage area.

From the Tools menu in DA, select “DQL Editor”.

The DQL page should open up. Copy and paste the following DQL query replacing ‘distributed_store’ with whatever name you chose for your distributed storage area above and press Execute button. Please be patient as this query might take while to finish.

UPDATE dm_sysobject (ALL) OBJECTS SET a_storage_type=’distributed_store’ where a_storage_type=’filestore_01′

After a few seconds or minutes, you should see a screen like the one below:

If this is a fresh content server installation, you should not get any errors. In case you do, try and resolve those errors first before moving on. The most likely and obvious cause of an error could be that the files are in use and could not be moved by Content Server. Try restarting the content server or deleting the files if they are not system or data files e.g. logs.

Finally, set the server time out value in primary server’s server.ini to 30 minutes. You do this by selecting “Edit Server.ini” from “Docbase” tab in Documentum Server Manager (Start menu->All Programs->Documentum->Documentum Server Manager), as show below:

Look for a section called [SERVER_STARTUP] and add the following entry as shown below:

client_session_timeout=30

Save the file and close notepad and Documentum Server Manager.

Now that we have moved all files to the new storage area, it is time for us to install and configure the remote content file server.

Copy the entire Documentum Installable on the server that is designated to become a remote file store. The installation will not work over a network. Extract the files on a local disk and double click a file called “serverWinSuiteSetup.exe”. The installation program should begin.

The installation program for Documentum is organized as follows:

The basic installation program that installs required content server binaries etc.
Once the base install is over, you can either choose to configure a new docbase or a remote content file server.
If you choose to configure a new docbase, then you can add a new docbroker and a new docbase
Or else, you can create a new docbroker and a new remote content file server.

As you can see, the base install is must for both docbase and file server installation. Follow the instructions in my previous post to complete the base installation. You know that the base install is over when you see a screen like this:

Choose “Configure Content-File Server for use with an existing repository” and press Next>.

The next screen is just an informative screen. Click Next. If you get a screen prompting you to restart you computer, restart. You should “Content File Server Configuration Program” after you log back in:

Press next to continue.

Enter the password for installation owner and press next. This username and password for installation owner has to be identical for primary content server and remote content file server (including domain) otherwise the setup will not work.

Enter the name of the docbroker for the PRIMARY content server (the one created in previous post). Installation program will use this docbroker to retrieve a list of repositories accordingly will create a remote content file server. Press next to continue.

You will be presented with a drop down list of repositories know to that docbroker. Select the repository you want to add a file store to and type in super user user name, password and domain. Click next.

You will be asked to select the connection mode for clients. Select Native and Secure and press next to continue.

On the following screen, specify a directory where you’d like to store content files for the distributed store and press Next. Note that this is the area where a users documents and other content files will be stored.

Again, enter the location for storing shared files -jars, dlls etc or just let it be a default location and press next.

The next screen will prompt you to enter a service name. This is the name of filestore’s service that will run on this distributed store machine. I usually go with the default choice (same as docbase name). Press next to continue with installation.

Okay, this is where the fun starts now. You should see a screen similar to the one below:

followed either by a success message (unlikely) or a screen with an error (most likely) message which looks like this and says “Error - cannot find source: dbpasswd.txt Please read error log C:\Documentum\product\6.5\install\dmadmin.ServerConfigurator.log for more information”

My experience tells me that this error can be caused by two reasons:

The DSN name for the database are different on primary and content file server. Check the names and if they are different, change the DSN name on the content file server to match the name on Primary server.
There is a bug in one of scripts that installer runs while configuring the remote content file server. The script is called dm_rcs_copyfiles.ebs. The bug surfaces if you specify a domain name in one of the previous screens. To make your way around this bug, click “OK” on the error message to come back to the “Service Name” screen. Go back 4 screens by clicking “Back” button 4 times to come to the Repository and username selection screen and delete the Repository Super User Domain. Click next and continue with installation.

The installation program caches the values entered by the user, so if even after changing DSN name or removing domain name you still get the error, quit the installation program completely and start remote content file server configuration program from scratch. To start the configuration program locate a file called cfsConfigurationProgram.exe in C:\Documentum\product\6.5\install and double click on it.

In you are lucky not to get the error first time, you should see a success screen saying that your configuration of a remote content file server is complete and successful.

The configuration program not only creates a local docbroker and a filestore, it also registers this file store in the primary content server. All you now need to do is add this filestore to the distributed storage area you created before and configure ACS and network locations. How exactly to configure, will be discussed in next post. Stay tuned!