The majority of this part of the GroupWise Interoperability Guide (Planning GroupWise in a Linux Cluster through Implementing the GroupWise Web Applications in a Cluster) is designed for those who are creating a new GroupWise system, or at least new domains and post offices, in the context of OES Cluster Services (NCS) on Linux.
If you already have an existing GroupWise system on OES Linux and need to configure it to work in a newly installed cluster, see Moving an Existing Linux GroupWise System into a Linux Cluster.
When you implement a new GroupWise system or a new domain or post office in a clustering environment, overall GroupWise system design does not need to change substantially. For a review, see Planning Your GroupWise System
in the GroupWise Installation Guide. However, the configuration of individual components of your GroupWise system will be significantly different. This section helps you plan the following GroupWise components in a cluster:
A new GroupWise system consisting of the primary domain and the initial post office
A new secondary domain
A new post office
The GroupWise agents: Message Transfer Agent (MTA), Post Office Agent (POA), and Document Viewer Agent (DVA)
During the planning process, component configuration alternatives are explained. For example, you might want the domain and post office together on the same shared partition or on different shared partitions.
The System Clustering Worksheet and the Agent Clustering Worksheet list the information you need as you set up GroupWise in a clustering environment. You should print these worksheets and fill them out as you complete the tasks listed below:
After you have completed the tasks and filled out the System Clustering Worksheet and the Agent Clustering Worksheet, you are ready to continue with Installing OES Cluster Services (NCS) on Linux.
Install OES Cluster Services (NCS) on OES Linux by following the instructions provided in the OES Cluster Services for Linux Administration Guide for your version of OES Linux.
The cluster installation process includes:
Meeting hardware and software requirements
Setting up a shared disk system
Creating a new Cluster object to represent the cluster in NetIQ eDirectory
Adding nodes to the cluster
Installing the OES Cluster Services software on all nodes in the cluster
Creating shared partitions, shared NSS volumes, or shared pools as needed for your cluster, as described in the OES Cluster Services for Linux Administration Guide for your version of OES Linux.
NOTE:For simplicity in this section, the term “shared partition” is intended to include any of these shared storage alternatives.
Cluster-enabling any of these shared storage alternatives, as described in the OES Cluster Services for Linux Administration Guide for your version of OES Linux.
IMPORTANT:Cluster-enabling is required for GroupWise.
Mounting the shared partitions where you want to set up GroupWise domains and post offices.
As you install OES Cluster Services on Linux, record key information about the cluster on the System Clustering Worksheet:
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SYSTEM CLUSTERING WORKSHEET |
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Under Item 1: eDirectory Tree for Cluster, record the name of the eDirectory tree where the new Cluster object has been created. Under Item 2: Cluster Name, record the name of the Cluster object that you created for your GroupWise system. Under Item 3: Cluster Context, record the full context of the Cluster object. Under Item 4: Nodes in Cluster, list the nodes that you have added to the cluster. Include the file system information about each partition, including file system type (nss, reiserfs, ext3, and so on), device name (sda2, hda1, and so on), and mount point directory (/media/nss, /mnt, /mail, and so on). You need this information when you set up the load and unload scripts for the GroupWise cluster resources. Under Item 5: Shared Partitions, list the volume names and volume IDs for the shared partitions that are available for use in your GroupWise system. You need this information when you set up the load and unload scripts for the GroupWise cluster resources. |
The number of nodes and shared partitions that are available in the cluster strongly influences where you can place GroupWise domains and post offices. You have several alternatives:
Your whole GroupWise system can run in a single cluster.
Parts of your GroupWise system can run in one cluster while other parts of it run in one or more other clusters.
Parts of your GroupWise system can run in a cluster while other parts run outside of the cluster, on non-clustered servers.
If you do not have the system resources to run all of your GroupWise system in a clustering environment, you must decide which parts have the most urgent need for the high availability provided by clustering. Here are some suggestions:
Post offices and their POAs must be available in order for users to access their GroupWise mailboxes. Therefore, post offices and their POAs are excellent candidates for the high availability provided by clustering.
Domains and their MTAs are less noticeable to users when they are unavailable (unless users in different post offices happen to be actively engaged in an email discussion when the MTA goes down). On the other hand, domains and their MTAs are critical to GroupWise administrators, although administrators might be more tolerant of a down server than end users are. Critical domains in your system are the primary domain and, if you have one, a hub or routing domain. These domains should be in the cluster, even if other domains are not.
The GWIA might or might not require high availability in your GroupWise system, depending on the importance of immediate messaging across the Internet and the use of POP3 or IMAP4 clients by GroupWise users.
The Monitor Agent is a vital partner with the GroupWise High Availability service, described in Installing the GroupWise Monitor Software
in the GroupWise Installation Guide. The GroupWise High Availability service automatically restarts agents that go down under circumstances that do not cause the entire server to go down. If you want this protection for your GroupWise agents, you can run the Monitor Agent in your cluster.
See also, Monitor and the GroupWise High Availability Service on Linux
in the GroupWise Installation Guide.
There is no right or wrong way to implement GroupWise in a clustering environment. It all depends on the specific needs of your particular GroupWise system and its users.
The considerations involved in planning a new domain in a clustering environment are essentially the same as for any other environment.
Primary Domain:
If you are setting up a new GroupWise system in a clustering environment, you are creating the primary domain as you complete the tasks in this section. To prepare, review Planning Your GroupWise System
and Installing the GroupWise Server Software
in the GroupWise Installation Guide, which includes links to the Simple GroupWise System Worksheet and the Primary Domain Worksheet. These cover planning the primary domain and an initial post office in the primary domain.
Secondary Domain:
If your GroupWise system already exists, you are creating a new secondary domain. To prepare, review Creating a New Domain
in the GroupWise Administration Guide, which includes a link to the Secondary Domain Worksheet.
Regardless of the type of domain you are creating, keep in mind the following cluster-specific details as you fill out the worksheet you need:
When you specify the location for the domain directory (and for a new GroupWise system, the post office directory) on the worksheet, remember that it will be on a GroupWise partition, not on the node where you will be running the GroupWise Installation program.
IMPORTANT:Configuring a domain or post office directly at the root of a cluster volume is not supported. An example of a root path on an NSS volume is /media/nss/GW. In this example, you need a sub-directory under GW when configuring your domain in order to avoid issues with GroupWise certificates.
A working example can be found in the Sample Cluster Load Script where DOM is the volume root with a sub-directory of utah.
Do not concern yourself with the GroupWise agent information on the worksheet. You will plan the agent installation later.
When you have completed the worksheet, transfer the key information from the Primary Domain Worksheet
or the Secondary Domain Worksheet
in the GroupWise Installation Guide to the System Clustering Worksheet.
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SYSTEM CLUSTERING WORKSHEET |
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Under Item 9: Domain Name, transfer the domain name and database directory to the System Clustering Worksheet. Under Item 7: GroupWise Partition for Domain, transfer the domain location to the System Clustering Worksheet. Also specify the secondary IP address of the shared partition where you plan to create the domain. |
IMPORTANT:Do not create the new domain until you are instructed to do so in Creating a New GroupWise System to Work with OES Cluster Services.
The considerations involved in planning a new post office in a clustering environment are essentially the same as for any other environment. The initial post office in a new GroupWise system on Linux is planned on the Post Office Worksheet. To plan additional new post offices, review Creating a New Post Office
in the GroupWise Administration Guide, which includes a link to the Post Office Worksheet. When you specify the location for the post office directory, remember that it will be on a GroupWise partition, not on the node where you will be running the GroupWise Installation program.
When you have completed the worksheet, transfer key information from the Post Office Worksheet to the System Clustering Worksheet.
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SYSTEM CLUSTERING WORKSHEET |
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Under Item 10: Post Office Name, transfer the post office name and database location to the System Clustering Worksheet. Also specify the secondary IP address of the shared partition where you plan to create the domain. If you will create the post office on a different GroupWise partition from where the domain is located, under Item 8: Shared Partition for Post Office, transfer the post office location to the System Clustering Worksheet. Also specify the secondary IP address of the shared partition where you plan to create the post office. |
IMPORTANT:Do not create the new post office until you are instructed to do so in Creating a New GroupWise System to Work with OES Cluster Services.
The considerations involved in planning a new library in a clustering environment are essentially the same as for any other environment. However, in a Linux cluster, you should not plan to locate a document storage area on a remote storage area. If you choose to place it outside the post office directory structure, it should still be located on the same server with the post office.
You can plan a library for a clustered post office by following the standard instructions provided in Creating and Managing Libraries
in the GroupWise Administration Guide and filling out the Library Worksheet
. Then provide the library information on the System Clustering Worksheet.
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SYSTEM CLUSTERING WORKSHEET |
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Under Item 11: Document Storage Area Location, mark where you want to create the library’s document storage area. |
IMPORTANT:Do not create the new library until you are instructed to do so in Creating a New GroupWise System to Work with OES Cluster Services.
There are several cluster-specific issues to consider as you plan to configure the Linux MTA, POA, and DVA in your clustered GroupWise system:
By default, the GroupWise agents listen on all IP addresses, both primary and secondary, that are bound to the server. This means that any time there is a possibility of two of the same type of agents loading on the same node, it is important that each agent use the appropriate secondary IP address of the GroupWise partition. The secondary IP address moves with each agent when it fails-over, so that, in the case of the POA, GroupWise clients do not lose their connections to the POA.
If you are planning to set up a GroupWise name server to help GroupWise clients locate their post offices, make sure that the default POA port number of 1677 is used somewhere in the cluster. For more information, see Simplifying Client Access with a GroupWise Name Server
in the GroupWise Administration Guide.
Clustering is not necessary in order to provide high availability for the DVA. As an alternative to clustering, you can install the DVA on multiple servers outside the cluster, as described in Scaling Your DVA Installation
in the GroupWise Administration Guide.
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AGENT CLUSTERING WORKSHEET |
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Under Item 3: MTA Network Information, transfer the domain secondary IP address from the System Clustering Worksheet to the Agent Clustering Worksheet. Under Item 6: POA Network Information, transfer the post office secondary IP address from the System Clustering Worksheet to the Agent Clustering Worksheet. Under Item 7: DVA Network Information, transfer the post office secondary IP address from the System Clustering Worksheet to the Agent Clustering Worksheet. |
By default, a GroupWise partition is configured to have all nodes in the cluster in its failover list, organized in ascending alphanumeric order. Only one node at a time can have a particular GroupWise partition mounted and active. If a GroupWise partition’s preferred node fails, the partition fails-over to the next node in the failover list. You should customize the failover list for each GroupWise partition based on the fan-out-failover principle.
When a node fails, its partitions should not all fail-over together to the same secondary node. Instead, the partitions should be distributed across multiple nodes in the cluster. This prevents any one node from shouldering the entire processing load typically carried by another node. In addition, some partitions should never have the potential of being mounted on the same node during a failover situation. For example, a post office and POA that service a large number of very active GroupWise client users should never fail-over to a node where another very large post office and heavily loaded POA reside. If they did, users on both post offices would notice a decrease in responsiveness of the GroupWise client.
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AGENT CLUSTERING WORKSHEET |
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Under Item 2: Domain Failover List, list the nodes that you want to have in the domain partition failover list. The MTA might need to run on any node that the domain partition fails over to. Therefore, you will install the agent software on all of the nodes in the domain failover list. If you are planning the post office on a different GroupWise partition from where the domain is located, under Item 5: Post Office Failover List, list the nodes that you want to have in the post office partition failover list. The POA (and the DVA if you installed along with the POA) might need to run on any node that the post office partition fails over to. Therefore, you will install the agent software on all of the nodes in the post office failover list. |
A cluster resource is a shared partition, secondary IP address, application, service, Web server, and so on, that can function successfully anywhere in the cluster. Cluster resources include the GroupWise agents and the Messenger agents. For example, you might create a /mnt/gwsystem mount point, or you might create /mnt/dom1 and /mnt/po1 mount points.
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AGENT CLUSTERING WORKSHEET |
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Under Item 8: Cluster Resource Information, list the mount point and secondary IP address for the GroupWise partition where the domain and post office will be located. |
Aside from the cluster-specific issues discussed in the preceding sections, the considerations involved in planning for the GroupWise Linux agents are the same in a clustering environment as for any other environment. Review Working with the GroupWise Agents
and Linux: Managing the GroupWise Agents
in the GroupWise Installation Guide.
IMPORTANT:Do not install the Linux agent software until you are instructed to do so in Creating a New GroupWise System to Work with OES Cluster Services.
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Item |
Explanation |
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1) eDirectory Tree for Cluster: |
Record the eDirectory tree where you created the new Cluster object when you installed OES Cluster Services for Linux. For more information, see Installing OES Cluster Services (NCS) on Linux |
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2) Cluster Name: Master IP Address: |
Record the name of the new Cluster object that you created for your GroupWise system. Also record the virtual IP address of the cluster that will remain constant regardless of which node is currently active. For more information, see Installing OES Cluster Services (NCS) on Linux. |
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3) Cluster Context: |
Record the full context where you created the new Cluster object. For more information, see Installing OES Cluster Services (NCS) on Linux. |
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4) Nodes in Cluster:
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List the nodes that are part of the cluster that you set up for your GroupWise system. Also list the file system type (reiserfs, ext3, and so on), device name (sda2, hda1, and so on), and mount point directory (/mnt, /mail, and so on) for each. You need this information as you create load and unload scripts for GroupWise agents. For more information, see Installing OES Cluster Services (NCS) on Linux. |
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5) Shared Partitions in Cluster:
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List the volume name and volume ID for each shared partition that is available for use in your GroupWise system. For more information, see Installing OES Cluster Services (NCS) on Linux. |
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6) GroupWise Partition for Software Distribution Directory: Secondary IP Address: Directory: |
If desired, specify the name of the shared partition where the GroupWise software distribution directory will reside and the full path to its location. For more information, see Introduction to GroupWise and OES Cluster Services on Linux. |
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7) GroupWise Partition for Domain: Secondary IP Address: Post Office on Same Partition as Domain?
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Specify the name of the shared partition where the GroupWise domain will reside and its secondary IP address. For more information, see Planning a New Clustered Domain. |
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8) GroupWise Partition for Post Office: Secondary IP Address: |
Specify the name of the shared partition where the GroupWise post office will reside and its secondary IP address. For more information, see Planning a New Clustered Post Office. |
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9) Domain Name: Domain Directory: |
Specify a unique name for the domain. Specify the directory on the GroupWise partition where you want to create the new domain. For more information, see Planning a New Clustered Domain. |
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10) Post Office Name: Post Office Directory: |
Specify a unique name for the post office. Specify the directory on the GroupWise partition where you want to create the post office. For more information, see Planning a New Clustered Post Office. |
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11) Document Storage Area Location:
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If you need a library for a clustered post office, mark where you want to create its document storage area and provide a directory if necessary. For more information, see Planning a New Library for a Clustered Post Office. |
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Item |
Explanation |
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1) Domain Name: Domain Location: |
Transfer this information from the System Clustering Worksheet (item 9). |
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2) Domain Failover List: |
List other nodes in the cluster where the GroupWise domain and its MTA can fail-over. For more information, see Determining Appropriate Failover Lists for the Linux Agents. |
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3) MTA Network Information:
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Record the MTA network address information for the server where the MTA will run. The MTA IP address is the same as the domain secondary IP address in the cluster. |
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4) Post Office Name: Post Office Location: |
Transfer this information from the System Clustering Worksheet (item 10). |
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5) Post Office Failover List: |
List other nodes in the cluster where the GroupWise post office and its POA can fail-over. For more information, see Determining Appropriate Failover Lists for the Linux Agents. |
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6) POA Network Information:
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Record the POA network address information for the server where the POA will run. The POA IP address is the same as the post office secondary IP address in the cluster. |
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7) DVA Network Information:
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If you are configuring the DVA along with the POA so that it can participate in the cluster, record the DVA network address information for the server where the DVA will run. When you install the DVA along with the POA, the DVA IP address is the same as the post office secondary IP address in the cluster. |
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8) Cluster Resource Information
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List the cluster resource information for the GroupWise partition where the domain and post office serviced by the agents are located. For more information, see Determining Cluster Resource Information for the Linux Agents. |