HP HA s Software manual Rules for Using the EMS Disk Monitor with MC/ServiceGuard

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Monitoring Disk Resources

Rules for Using the EMS Disk Monitor with MC/ServiceGuard

Rules for Using the EMS Disk Monitor with MC/ServiceGuard

The disk monitor is designed especially for use with MC/ServiceGuard to provide package failover if host adapters, busses, controllers, or disks fail. Here are some examples:

•In a cluster where one copy of data is shared between all nodes in a cluster, you may want to fail over a package if the host adapter has failed on the node running the package. Because busses, controllers, and disks are shared, package fail over to another node because of bus, controller, or disk failure would not successfully run the package. To make sure you have proper failover in a shared data environment, you must create identical package dependencies on all nodes in the cluster. MC/ServiceGuard can then compare the resource “UP” values on all nodes and fail over to the node that has the correct resources available.

•In a cluster where each node has its own copy of data, you may want to fail over a package to another node for any number of reasons:

•host adapter, bus, controller, or disk failure

•unprotected data (the number of copies is reduced to one)

•performance has degraded because one of the PV links has failed

For example, in a cluster of web servers where each node has a copy of the data and users are distributed for load balancing, you can fail over a package to another node with the correct resources available. Again, the package resource dependencies should be conﬁgured the same on all nodes.

Disk availability is based on pv_summary. See “Conﬁguring MC/ServiceGuard Package Dependencies” in Chapter 1 for information on conﬁguring package dependencies.

In addition to conﬁguring disks as MC/ServiceGuard package dependencies, you may also want to have alerts sent to a system management tool such as HP OpenView IT/Operations or Network Node Manager. Although MC/ServiceGuard and EMS work together to provide package failover, they do not send events or log the source of the failure. Also, failures may not cause a package to fail over, but may expose a single point of failure that you want to know about. Therefore, it is recommended you also conﬁgure requests from the SAM interface to EMS.

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Chapter 2

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Contents Using EMS HA Monitors B5735-90001 AugustLegal Notices Contents Monitoring Cluster Resources Monitoring Network InterfacesMonitoring System Resources TroubleshootingGlossary Contents Printing Date Part Number Edition Printing HistoryB5735-90001 Page Preface PublicationsPage Installing and Using EMS Event Monitoring Services High Availability Monitors What are EMS HA Monitors?Chapter Role of EMS HA Monitors in a High Availability Environment Installing and Removing EMS HA Monitors Installing EMS HA MonitorsRemoving EMS HA Monitors Using EMS HA Monitors Event Monitoring Service Resource Class HierarchyStatus AvailMB PvpvlinkEvent Monitoring Service Screen Selecting a Resource to Monitor ScreenUsing Wildcards Creating a Monitoring Request Monitoring Request ParametersHow Do I Tell EMS When to Send Events? What is a Polling Interval? Which Protocols Can I Use to Send Events?What is a Notiﬁcation Comment? Modifying Monitoring Requests Copying Monitoring RequestsRemoving Monitoring Requests Conﬁguring MC/ServiceGuard Package Dependencies Service EMSPackage Conﬁguration Screen Package Resource Dependencies Screen Resource Parameters Screen Using EMS HA Monitors Monitoring Disk Resources Monitoring Disk Resources Disk Monitor Reference Disk Monitor Resource Class HierarchyPhysical Volume Summary Interpreting Physical Volume SummaryDisk Monitor Reference Physical Volume and Physical Volume Link Status Interpreting Physical Volume and Physical Volume Link StatusLogical Volume Summary Interpreting Logical Volume SummaryLogical Volume Status Interpreting Logical Volume StatusLogical volume is inactive Logical volume is DOWN, a complete copy of the data is notLogical Volume Number of Copies Interpreting Logical Volume CopiesRules for Using the EMS Disk Monitor with MC/ServiceGuard Rules for Using the EMS Disk Monitor with MC/ServiceGuard Rules for RAID Arrays Pvsummary Calculations Case Conclusion StateCreating Volume Groups on Disk Arrays Using PV Links Adding PVGs to Existing Volume Groups# mkdir /dev/vgdatabase Creating Logical Volumes Rules for Mirrored Individual Disks Creating Disk Monitoring Requests Disk Monitoring Request Suggestions Parameters When Disks Fail Resources to Monitor for RAID Arrays RAID Array ExamplePvgup Return Resources to Monitor for Mirrored Disks Mirrored Disks ExampleMonitoring Parameters Resource Notify Condition Option Resources to Monitor for Lock Disks Example for Interpreting the pvsummary for Mirrored DisksNumber Pvsummary Valid Meaning Value Devices Resource Monitoring Parameters Notify Condition OptionResources to Monitor for Root Volumes Monitoring Cluster Resources Cluster Monitor Resource Class Hierarchy Cluster Monitor ReferenceCluster Cluster Status Interpreting Custer StatusNode Status Interpreting Node StatusPackage Status Interpreting Package StatusCreating Cluster Monitoring Requests Monitoring Network Interfaces Network Monitor Resource Class Hierarchy Network Monitor ReferenceInterpreting LAN Interface Status Chapter Net/interfaces/lan/status/LANname When value is Conﬁguring Network Monitoring Requests30 sec HourMonitoring System Resources System Monitor Reference System Resource Monitor Class HierarchyInterpreting Number of Users Number of UsersResource Name Value Range Interpretation Interpreting Job Queues Job QueuesResource Name Value Interpretation Range Filesystem Available Space Filesystem Available SpaceResource Name Creating System Resource Monitoring Requests 6Troubleshooting EMS Directories and Files Etc/opt/resmon/log Logging and tracing EMS LoggingEMS Tracing Network Performance Issues System Performance IssuesPerformance Considerations Testing Monitor Requests Testing Disk Monitor RequestsTesting Cluster Monitor Requests Testing Network Monitor RequestsMaking Sure Monitors are Running Glossary Notiﬁcation See alert Glossary Glossary Index Index Index