InfoScale™ 9.0 Cluster Server Administrator's Guide - Windows
- Section I. Clustering concepts and terminology
- Introducing Cluster Server
- About Cluster Server
- About cluster control guidelines
- About the physical components of VCS
- Logical components of VCS
- Types of service groups
- Agent classifications
- About cluster control, communications, and membership
- About security services
- About cluster topologies
- VCS configuration concepts
- Introducing Cluster Server
- Section II. Administration - Putting VCS to work
- About the VCS user privilege model
- Getting started with VCS
- Administering the cluster from the command line
- About administering VCS from the command line
- Stopping the VCS engine and related processes
- About managing VCS configuration files
- About managing VCS users from the command line
- About querying VCS
- About administering service groups
- Modifying service group attributes
- About administering resources
- About administering resource types
- About administering clusters
- Configuring resources and applications in VCS
- About configuring resources and applications
- About Virtual Business Services
- About Intelligent Resource Monitoring (IMF)
- About fast failover
- How VCS monitors storage components
- About storage configuration
- About configuring network resources
- About configuring file shares
- About configuring IIS sites
- About configuring services
- Before you configure a service using the GenericService agent
- About configuring processes
- About configuring Microsoft Message Queuing (MSMQ)
- About configuring the infrastructure and support agents
- About configuring applications using the Application Configuration Wizard
- Adding resources to a service group
- About application monitoring on single-node clusters
- Configuring the service group in a non-shared storage environment
- About the VCS Application Manager utility
- About testing resource failover using virtual fire drills
- Modifying the cluster configuration
- Section III. Administration - Beyond the basics
- Controlling VCS behavior
- VCS behavior on resource faults
- About controlling VCS behavior at the service group level
- Customized behavior diagrams
- VCS behavior for resources that support the intentional offline functionality
- About controlling VCS behavior at the resource level
- Service group workload management
- Sample configurations depicting workload management
- The role of service group dependencies
- VCS event notification
- VCS event triggers
- List of event triggers
- Controlling VCS behavior
- Section IV. Cluster configurations for disaster recovery
- Connecting clusters–Creating global clusters
- VCS global clusters: The building blocks
- About global cluster management
- About serialization - The Authority attribute
- Prerequisites for global clusters
- Setting up a global cluster
- Configuring replication resources in VCS
- About IPv6 support with global clusters
- About cluster faults
- About setting up a disaster recovery fire drill
- Test scenario for a multi-tiered environment
- Administering global clusters from Cluster Manager (Java console)
- Administering global clusters from the command line
- About global querying in a global cluster setup
- Administering clusters in global cluster setup
- Setting up replicated data clusters
- Connecting clusters–Creating global clusters
- Section V. Troubleshooting and performance
- VCS performance considerations
- How cluster components affect performance
- How cluster operations affect performance
- VCS performance consideration when a system panics
- VCS agent statistics
- Troubleshooting and recovery for VCS
- VCS message logging
- Handling network failure
- Troubleshooting VCS startup
- Troubleshooting service groups
- Troubleshooting and recovery for global clusters
- VCS utilities
- VCS performance considerations
- Section VI. Appendixes
- Appendix A. VCS user privileges—administration matrices
- Appendix B. Cluster and system states
- Appendix C. VCS attributes
- Appendix D. Configuring LLT over UDP
- Appendix E. Handling concurrency violation in any-to-any configurations
- Appendix F. Accessibility and VCS
- Appendix G. Executive Order logging
About resources and resource dependencies
Resources are hardware or software entities that make up the application. Disk groups and file systems, network interface cards (NIC), IP addresses, and applications are a few examples of resources.
Resource dependencies indicate resources that depend on each other because of application or operating system requirements. Resource dependencies are graphically depicted in a hierarchy, also called a tree, where the resources higher up (parent) depend on the resources lower down (child).
Figure: Sample resource dependency graph shows the hierarchy for a database application.
Resource dependencies determine the order in which resources are brought online or taken offline. For example, you must import a disk group before volumes in the disk group start, and volumes must start before you mount file systems. Conversely, you must unmount file systems before volumes stop, and volumes must stop before you deport disk groups.
A parent is brought online after each child is brought online, and this continues up the tree, until finally the application starts. Conversely, to take a managed application offline, VCS stops resources by beginning at the top of the hierarchy. In this example, the application stops first, followed by the database application. Next the IP address and file systems stop concurrently. These resources do not have any resource dependency between them, and this continues down the tree.
Child resources must be brought online before parent resources are brought online. Parent resources must be taken offline before child resources are taken offline. If resources do not have parent-child interdependencies, they can be brought online or taken offline concurrently.
A new type of resource dependency has been introduced wherein a parent resource can depend on a set of child resources. The parent resource is brought online or remains online only if a minimum number of child resources in this resource set are online.
For example, if an application depends on five IPs and if this application has to be brought online or has to remain online, at least two IPs must be online. You can configure this dependency as shown in the figure below.
The system creates a set of child IP resources and the application resource will depend on this set. For this example, the assumption is that the application resource is res1 and the child IP resources are res2, res3, res4, res5, and res6.
If two or more IP resources come online, the application attempts to come online. If the number of online resources falls below the minimum requirement, (in this case: 2), resource fault is propagated up the resource dependency tree.
Note:
Arctera InfoScale Operations Manager and Java GUI does not support atleast resource dependency and so the dependency is shown as normal resource dependency.