New clustering approach in IBM Lotus Connections v2.5

Introduction

The Lotus Connections 2.5 installation wizard is a powerful tool with which you can install Lotus Connection in a stand-alone environment or a cluster environment.

Lotus Connections 2.5 adds many new features, such as Files and Wikis, to the previous 2.0.1 version. The version 2.5 installation wizard also has big changes, while integrating the functionality of the v2.0.1 cluster wizard, allowing you to easily set up a Connections cluster environment.

In this article we describe this new approach to installing a Lotus Connections network deployment, and also discuss the detailed steps to troubleshoot errors that may occur.

Overview

Here we define the term “cluster” to mean an installation on two or more sets of application servers that are grouped to share the application's (for example, Communities) workload. Clustering can provide better performance and improved availability of features, compared with a stand-alone deployment, and is a useful deployment selection in a production environment.

Generally speaking, there are three steps to create a cluster for an enterprise application in a WebSphere Application Server environment:

1. Install the enterprise application on the WebSphere Application Server server in any one of nodes.
2. Federate the node to a cell, using the addNode command.
3. Create the cluster via the wsadmin command or via the Deployment Manager (DM) administrative console.

Figure 1 shows an example cluster deployment using the Communities feature.

Figure 1. Connections cluster deployment of the Communities feature

Benefits of the new cluster deployment

In contrast to version 2.0.1, Lotus Connections 2.5 leverages WebSphere Application Server clustering technology as much as possible. After installing Lotus Connections on the first cluster member server, you can use the first cluster member server as a template to create additional cluster members on secondary nodes. This provides a more flexible approach to extend or reduce clustering throughput.

Other benefit of the new cluster deployment include:

• Simplified clustering deployment steps. Now you can quickly set up the cluster for Lotus Connections 2.5 without running the Connections installer on each of the nodes. In version 2.0.1, you had to install Lotus Connections on every node, which increased the installation time, as well as the maintenance time.

Table 1 compares the main steps of creating clusters for Connections versions 2.0.1 and 2.5.

Table 1. Comparison of version 2.0.1 and 2.5 clustering steps

	2.0.1	2.5
Prerequisite step	Install WAS ND version, then create: dmgr profiles stand profiles	Install WAS ND version, then create: dmgr profiles stand profiles
Step 1	Run the installation wizard on first node: install stand-alone Connections	Run installation wizard on first node: Install stand-alone Connections federate first node into cell, create cluster
Step 2	Run installation wizard on subsequent node: Install stand-alone Connections	Add subsequent node into cell: run addNode.bat/sh to federate node into cell create new cluster member on subsequent node via administrative console
Step 3	Add first node into cell: modify wkplc_comp.properties file manually run cluster wizard to create cluster for one feature run cluster wizard again for another feature, and so on.	No need
Step 4	Add secondary node into cell modify wkplc_comp.properties file manually run cluster wizard to create cluster for one feature run cluster wizard again for another feature, and so on.	No need

• Support of flexible increases and decreases of the cluster scope. The topology can be easily managed within the DM administrative console, including:

• Adding or removing a subsequent server member to the cluster
• Adding or removing secondary nodes

Installing the cluster

Since the Connections v2.0.1 cluster wizard is integrated into Connections v2.5, you can use the steps below to create a cluster during the install of Lotus Connections features:

1. Use Connections installation wizard v2.5 to install the first node of the cluster by first selecting “Network deployment” in the deployment selection window (see figure 2). Click Next.

Figure 2. Deployment selection window


2. In the Install type window, if this is a first cluster to be created, choose “Install the first node of a cluster”; if you've installed a stand-alone deployment and want to convert it to a cluster, choose “Convert an existing stand-alone deployment to network deployment” (see figure 3). Click Next.

Figure 3. Install type window



3. Enter the Deployment Manager host, port, user name, and password in the Deployment Manager information window (see figure 4). Click Next.

Figure 4. Deployment Manager properties window


4. Enter the cluster name for every feature selected to install; click Next (see figure 5).

Figure 5. Specify cluster names window



For more detailed information, refer to the Lotus Connections 2.5 Information Center topic, Installing the first node of a cluster.

After installing the first node, perform these two steps to add a new member to the cluster:

1. Federate the node by running addnode.bat on the node
2. Add new cluster server members via the DM administrative console

For further information, refer to the Information Center topic, Adding subsequent nodes to a cluster.

Troubleshooting tips

If you encounter a problem with running the installation wizard to install a Lotus Connections cluster environment, you need to perform some basic diagnostics and verify your system’s configuration. This section provides important information about how to troubleshoot a problem.

In general you can verify the installation results by checking whether:

(1) there are any error messages in the installation results window.
(2) there are exceptions in the installation log file.
(3) the newly created cluster can start up correctly from the DM administrative console.

Below are some issues that lead to installation failures during network deployment and their causes, against which you can check your environment.

• Not enough space. Make sure you have 500MB of space in the directory.

• Failed to authenticate user for accessing Service Integration Bus (SIBus). An SIBus is a group of one or more application servers in a WebSphere Application Server cell that cooperate to provide asynchronous messaging services. Make sure the administrative user who was specified during install is correct. For a network deployment you must enter the DM administrative user.

• Failed to create server instance. Make sure there is no special character instance name, such as #, $, ^, space, etc.

• Failed to install the first node. Make sure the node in which you are installing is not a managed node. The Connections 2.5 installer wizard must run on an unmanaged node, since it can federate this node into the cell automatically, and it is not supported to run on the DM directly.

• Failed to federate node. Ensure that you don't open any subdirectory under /profiles//config/cells/; otherwise, the federation of node will fail because it can't change the name of the cell directory.

• Failed to add server process into cluster. Ensure you input the correct value for the cluster member name. This value should be unique for the cluster (this issue is especially common on the secondary node). Also ensure the system application Filetransfer has been installed on the DM (this should be installed by default).

Recovery

If the network deployment install fails, you need to recover the environment before re-installing. There are two cases to check:

• If there is a failure before the node is federated: In this case, correct the problem, and then run the installation wizard to convert the stand-alone node to a cluster.

• If there is a failure after node is federated: In this case, first un-federate the node from the DM administrative console, remove configuration items from the DM according to the manual uninstall instructions in the Information Center, and then run the installation wizard.

Conclusion

Hopefully you now have a good understanding of cluster deployment in Lotus Connections v2.5, and how to troubleshoot potential issues within a cluster environment.

Resources

Lotus Connections 2.5 Information Center:
http://publib.boulder.ibm.com/infocenter/ltscnnct/v2r0/index.jsp

developerWorks Lotus Connections 2.5 product page:
http://www.ibm.com/developerworks/lotus/products/connections/?S_TACT=105AGX13&S_CMP=LP

IBM Lotus Connections 2.5 Reviewer's Guide:
http://www.ibm.com/developerworks/lotus/documentation/connections/dw-l-reviewersguide/

Lotus Connections Forum:
http://www-10.lotus.com/ldd/lcforum.nsf?OpenDatabase

About the authors

Bai Jian Su is a Staff Software Engineer working on the Installation and Forum teams for Lotus Connections. You can reach him at subaij@cn.ibm.com.

Zheng Jun Song is a Software Engineer working with the Level 3 Support team for Lotus Connections. You can reach him at songzj@cn.ibm.com.