Storage Foundation for Sybase ASE CE 7.4 Administrator's Guide - Linux
- Overview of Storage Foundation for Sybase ASE CE
- About Storage Foundation for Sybase ASE CE
- How SF Sybase CE works (high-level perspective)
- About SF Sybase CE components
- About optional features in SF Sybase CE
- How the agent makes Sybase highly available
- About Veritas InfoScale Operations Manager
- Administering SF Sybase CE and its components
- Administering SF Sybase CE
- Setting the environment variables for SF Sybase CE
- Starting or stopping SF Sybase CE on each node
- Applying operating system updates on SF Sybase CE nodes
- Adding storage to an SF Sybase CE cluster
- Recovering from storage failure
- Enhancing the performance of SF Sybase CE clusters
- Verifying the nodes in an SF Sybase CE cluster
- Administering VCS
- Viewing available Veritas device drivers
- Starting and stopping VCS
- Environment variables to start and stop VCS modules
- Adding and removing LLT links
- Configuring aggregated interfaces under LLT
- Displaying the cluster details and LLT version for LLT links
- Configuring destination-based load balancing for LLT
- Enabling and disabling intelligent resource monitoring for agents manually
- Administering the AMF kernel driver
- Administering I/O fencing
- About administering I/O fencing
- About the vxfentsthdw utility
- General guidelines for using the vxfentsthdw utility
- About the vxfentsthdw command options
- Testing the coordinator disk group using the -c option of vxfentsthdw
- Performing non-destructive testing on the disks using the -r option
- Testing the shared disks using the vxfentsthdw -m option
- Testing the shared disks listed in a file using the vxfentsthdw -f option
- Testing all the disks in a disk group using the vxfentsthdw -g option
- Testing a disk with existing keys
- About the vxfenadm utility
- About the vxfenclearpre utility
- About the vxfenswap utility
- Enabling or disabling the preferred fencing policy
- About I/O fencing log files
- Administering CVM
- Establishing CVM cluster membership manually
- Changing the CVM master manually
- Importing a shared disk group manually
- Deporting a shared disk group manually
- Verifying if CVM is running in an SF Sybase CE cluster
- Verifying CVM membership state
- Verifying the state of CVM shared disk groups
- Verifying the activation mode
- Administering CFS
- Administering the Sybase agent
- Sybase agent functions
- Monitoring options for the Sybase agent
- Using the IPC Cleanup feature for the Sybase agent
- Configuring the service group Sybase using the command line
- Bringing the Sybase service group online
- Taking the Sybase service group offline
- Modifying the Sybase service group configuration
- Viewing the agent log for Sybase
- Administering SF Sybase CE
- Troubleshooting SF Sybase CE
- About troubleshooting SF Sybase CE
- Restarting the installer after a failed network connection
- Installer cannot create UUID for the cluster
- Troubleshooting I/O fencing
- The vxfentsthdw utility fails when SCSI TEST UNIT READY command fails
- Node is unable to join cluster while another node is being ejected
- System panics to prevent potential data corruption
- Cluster ID on the I/O fencing key of coordinator disk does not match the local cluster's ID
- Fencing startup reports preexisting split-brain
- Registered keys are lost on the coordinator disks
- Replacing defective disks when the cluster is offline
- Troubleshooting Cluster Volume Manager in SF Sybase CE clusters
- Restoring communication between host and disks after cable disconnection
- Shared disk group cannot be imported in SF Sybase CE cluster
- Error importing shared disk groups in SF Sybase CE cluster
- Unable to start CVM in SF Sybase CE cluster
- CVM group is not online after adding a node to the SF Sybase CE cluster
- CVMVolDg not online even though CVMCluster is online in SF Sybase CE cluster
- Shared disks not visible in SF Sybase CE cluster
- Troubleshooting interconnects
- Troubleshooting Sybase ASE CE
- Prevention and recovery strategies
- Prevention and recovery strategies
- Verification of GAB ports in SF Sybase CE cluster
- Examining GAB seed membership
- Manual GAB membership seeding
- Evaluating VCS I/O fencing ports
- Verifying normal functioning of VCS I/O fencing
- Managing SCSI-3 PR keys in SF Sybase CE cluster
- Identifying a faulty coordinator LUN
- Starting shared volumes manually
- Listing all the CVM shared disks
- I/O Fencing kernel logs
- Prevention and recovery strategies
- Tunable parameters
- Appendix A. Error messages
How intelligent resource monitoring works
When an IMF-aware agent starts up, the agent initializes with the IMF notification module. After the resource moves to a steady state, the agent registers the details that are required to monitor the resource with the IMF notification module. For example, the process agent registers the PIDs of the processes with the IMF notification module. The agent's imf_getnotification function waits for any resource state changes. When the IMF notification module notifies the imf_getnotification function about a resource state change, the agent framework runs the monitor agent function to ascertain the state of that resource. The agent notifies the state change to VCS which takes appropriate action.
A resource moves into a steady state when any two consecutive monitor agent functions report the state as ONLINE or as OFFLINE. The following are a few examples of how steady state is reached.
When a resource is brought online, a monitor agent function is scheduled after the online agent function is complete. Assume that this monitor agent function reports the state as ONLINE. The next monitor agent function runs after a time interval specified by the MonitorInterval attribute. If this monitor agent function too reports the state as ONLINE, a steady state is achieved because two consecutive monitor agent functions reported the resource state as ONLINE. After the second monitor agent function reports the state as ONLINE, the registration command for IMF is scheduled. The resource is registered with the IMF notification module and the resource comes under IMF control.The default value of MonitorInterval is 60 seconds.
A similar sequence of events applies for taking a resource offline.
Assume that IMF is disabled for an agent type and you enable IMF for the agent type when the resource is ONLINE. The next monitor agent function occurs after a time interval specified by MonitorInterval. If this monitor agent function again reports the state as ONLINE, a steady state is achieved because two consecutive monitor agent functions reported the resource state as ONLINE.
A similar sequence of events applies if the resource is OFFLINE initially and the next monitor agent function also reports the state as OFFLINE after you enable IMF for the agent type.