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
VCS behavior when an online resource faults
In the following example, a resource in an online state is reported as being offline without being commanded by the agent to go offline.
VCS goes through the following steps when an online resource faults:
VCS first verifies the Monitor routine completes successfully in the required time. If it does, VCS examines the exit code returned by the Monitor routine. If the Monitor routine does not complete in the required time, VCS looks at the FaultOnMonitorTimeouts (FOMT) attribute.
If FOMT=0, the resource will not fault when the Monitor routine times out. VCS considers the resource online and monitors the resource periodically, depending on the monitor interval.
If FOMT=1 or more, VCS compares the CurrentMonitorTimeoutCount (CMTC) with the FOMT value. If the monitor timeout count is not used up, CMTC is incremented and VCS monitors the resource in the next cycle.
If FOMT= CMTC, this means that the available monitor timeout count is exhausted and VCS must now take corrective action. VCS checks the Frozen attribute for the service group. If the service group is frozen, VCS declares the resource faulted and calls the resfault trigger. No further action is taken.
If the service group is not frozen, VCS checks the ManageFaults attribute at the resource level. VCS marks the resource as ONLINE|ADMIN_WAIT and fires the resadminwait trigger if its group-level value is NONE or if its resource-level value is IGNORE. If ManageFaults is set to ACT at the resource level or ALL at the group level, VCS invokes the Clean function with the reason Monitor Hung.
Note:
The resource-level ManageFaults value supersedes the corresponding service group-level value. VCS honors the service group-level ManageFaults value only when the corresponding resource-level value is blank ("").
If the Clean function is successful (that is, Clean exit code = 0), VCS examines the value of the RestartLimit attribute. If Clean fails (exit code = 1), the resource remains online with the state UNABLE TO OFFLINE. VCS fires the resnotoff trigger and monitors the resource again.
If the Monitor routine does not time out, it returns the status of the resource as being online or offline.
If the ToleranceLimit (TL) attribute is set to a non-zero value, the Monitor cycle returns offline (exit code = 100) for a number of times specified by the ToleranceLimit and increments the ToleranceCount (TC). When the ToleranceCount equals the ToleranceLimit (TC = TL), the agent declares the resource as faulted.
If the Monitor routine returns online (exit code = 110) during a monitor cycle, the agent takes no further action. The ToleranceCount attribute is reset to 0 when the resource is online for a period of time specified by the ConfInterval attribute.
If the resource is detected as being offline a number of times specified by the ToleranceLimit before the ToleranceCount is reset (TC = TL), the resource is considered faulted.
After the agent determines the resource is not online, VCS checks the Frozen attribute for the service group. If the service group is frozen, VCS declares the resource faulted and calls the resfault trigger. No further action is taken.
If the service group is not frozen, VCS checks the ManageFaults attribute. If ManageFaults=NONE, VCS marks the resource state as ONLINE|ADMIN_WAIT and calls the resadminwait trigger. If ManageFaults=ALL, VCS calls the Clean function with the CleanReason set to Unexpected Offline.
If the Clean function fails (exit code = 1) the resource remains online with the state UNABLE TO OFFLINE. VCS fires the resnotoff trigger and monitors the resource again. The resource enters a cycle of alternating Monitor and Clean functions until the Clean function succeeds or a user intervenes.
If the Clean function is successful, VCS examines the value of the RestartLimit (RL) attribute. If the attribute is set to a non-zero value, VCS increments the RestartCount (RC) attribute and invokes the Online function. This continues till the value of the RestartLimit equals that of the RestartCount. At this point, VCS attempts to monitor the resource.
If the Monitor returns an online status, VCS considers the resource online and resumes periodic monitoring. If the monitor returns an offline status, the resource is faulted and VCS takes actions based on the service group configuration.