Storage Foundation for Oracle® RAC 7.3.1 Administrator's Guide - Linux

Last Published:
Product(s): InfoScale & Storage Foundation (7.3.1)
  1. Section I. SF Oracle RAC concepts and administration
    1. Overview of Storage Foundation for Oracle RAC
      1. About Storage Foundation for Oracle RAC
        1.  
          Benefits of SF Oracle RAC
      2.  
        How SF Oracle RAC works (high-level perspective)
      3. Component products and processes of SF Oracle RAC
        1. Communication infrastructure
          1.  
            Data flow
          2.  
            Communication requirements
        2. Cluster interconnect communication channel
          1. About Low Latency Transport (LLT)
            1.  
              How LLT supports RDMA capability for faster interconnects between applications
          2.  
            Group Membership Services/Atomic Broadcast
        3.  
          Low-level communication: port relationship between GAB and processes
        4. Cluster Volume Manager (CVM)
          1.  
            CVM architecture
          2.  
            CVM communication
          3.  
            CVM recovery
          4.  
            Configuration differences with VxVM
          5. About Flexible Storage Sharing
            1.  
              Flexible Storage Sharing use cases
            2.  
              Limitations of Flexible Storage Sharing
        5. Cluster File System (CFS)
          1.  
            CFS architecture
          2.  
            CFS communication
          3.  
            CFS file system benefits
          4.  
            CFS configuration differences
          5.  
            CFS recovery
          6.  
            Comparing raw volumes and CFS for data files
        6. Cluster Server (VCS)
          1.  
            VCS architecture
          2. VCS communication
            1.  
              About the IMF notification module
          3. About resource monitoring
            1.  
              How intelligent resource monitoring works
          4.  
            Cluster configuration files
        7.  
          About I/O fencing
        8. Oracle RAC components
          1. Oracle Clusterware/Grid Infrastructure
            1.  
              Co-existence with VCS
          2.  
            Oracle Cluster Registry
          3. Application resources
            1.  
              Resource profiles
            2.  
              Oracle Clusterware/Grid Infrastructure node applications
            3.  
              Voting disk
        9. Oracle Disk Manager
          1.  
            ODM architecture
          2.  
            Veritas ODM performance enhancements
          3.  
            ODM communication
        10. RAC extensions
          1.  
            Veritas Cluster Server membership manager
          2.  
            Oracle and cache fusion traffic
      4.  
        Periodic health evaluation of SF Oracle RAC clusters
      5. About Virtual Business Services
        1.  
          Features of Virtual Business Services
        2.  
          Sample virtual business service configuration
      6.  
        About Veritas InfoScale Operations Manager
      7.  
        About Veritas Services and Operations Readiness Tools (SORT)
    2. Administering SF Oracle RAC and its components
      1. Administering SF Oracle RAC
        1.  
          Setting the environment variables for SF Oracle RAC
        2. Starting or stopping SF Oracle RAC on each node
          1.  
            Starting SF Oracle RAC using the script-based installer
          2.  
            Starting SF Oracle RAC manually on each node
          3.  
            Stopping SF Oracle RAC using the script-based installer
          4.  
            Stopping SF Oracle RAC manually on each node
        3.  
          Applying Oracle patches on SF Oracle RAC nodes
        4.  
          Migrating Pluggable Databases (PDB) between Container Databases (CDB)
        5.  
          Installing Veritas Volume Manager, Veritas File System, or ODM patches on SF Oracle RAC nodes
        6.  
          Applying operating system updates on SF Oracle RAC nodes
        7.  
          Adding storage to an SF Oracle RAC cluster
        8.  
          Recovering from storage failure
        9.  
          Backing up and restoring Oracle database using Veritas NetBackup
        10.  
          Enhancing the performance of SF Oracle RAC clusters
        11.  
          Administering SmartIO
        12.  
          Creating snapshots for offhost processing
        13.  
          Managing database storage efficiently using SmartTier
        14.  
          Optimizing database storage using Thin Provisioning and SmartMove
        15.  
          Scheduling periodic health checks for your SF Oracle RAC cluster
        16.  
          Using environment variables to start and stop VCSMM modules
        17.  
          Verifying the nodes in an SF Oracle RAC cluster
      2. Administering VCS
        1.  
          About managing VCS modules
        2.  
          Viewing available Veritas device drivers
        3.  
          Starting and stopping VCS
        4.  
          Environment variables to start and stop VCS modules
        5.  
          Adding and removing LLT links
        6.  
          Configuring aggregated interfaces under LLT
        7.  
          Displaying the cluster details and LLT version for LLT links
        8.  
          Configuring destination-based load balancing for LLT
        9.  
          Enabling and disabling intelligent resource monitoring for agents manually
        10.  
          Administering the AMF kernel driver
      3. Administering I/O fencing
        1.  
          About administering I/O fencing
        2. About the vxfentsthdw utility
          1.  
            General guidelines for using the vxfentsthdw utility
          2.  
            About the vxfentsthdw command options
          3. Testing the coordinator disk group using the -c option of vxfentsthdw
            1.  
              Removing and replacing a failed disk
          4.  
            Performing non-destructive testing on the disks using the -r option
          5.  
            Testing the shared disks using the vxfentsthdw -m option
          6.  
            Testing the shared disks listed in a file using the vxfentsthdw -f option
          7.  
            Testing all the disks in a disk group using the vxfentsthdw -g option
          8.  
            Testing a disk with existing keys
        3. About the vxfenadm utility
          1.  
            About the I/O fencing registration key format
          2.  
            Displaying the I/O fencing registration keys
          3.  
            Verifying that the nodes see the same disk
        4. About the vxfenclearpre utility
          1.  
            Removing preexisting keys
        5. About the vxfenswap utility
          1.  
            Replacing I/O fencing coordinator disks when the cluster is online
          2.  
            Replacing the coordinator disk group in a cluster that is online
          3.  
            Adding disks from a recovered site to the coordinator disk group
          4.  
            Refreshing lost keys on coordinator disks
        6.  
          Enabling or disabling the preferred fencing policy
        7.  
          About I/O fencing log files
        8.  
          Migrating from disk-based fencing to server-based fencing using the installer
        9.  
          Migrating from server-based fencing to disk-based fencing using the installer
      4. Administering the CP server
        1.  
          Refreshing registration keys on the coordination points for server-based fencing
        2.  
          Replacing coordination points for server-based fencing in an online cluster
        3.  
          Migrating from non-secure to secure setup for CP server and SF Oracle RAC cluster communication
      5. Administering CFS
        1.  
          Adding CFS file systems to a VCS configuration
        2.  
          Resizing CFS file systems
        3.  
          Verifying the status of CFS file system nodes and their mount points
      6. Administering CVM
        1.  
          Listing all the CVM shared disks
        2.  
          Establishing CVM cluster membership manually
        3. Changing the CVM master manually
          1.  
            Considerations for changing the master manually
          2.  
            Errors during CVM master switching
        4.  
          Importing a shared disk group manually
        5.  
          Deporting a shared disk group manually
        6.  
          Starting shared volumes manually
        7.  
          Verifying if CVM is running in an SF Oracle RAC cluster
        8.  
          Verifying CVM membership state
        9.  
          Verifying the state of CVM shared disk groups
        10.  
          Verifying the activation mode
      7. Administering Flexible Storage Sharing
        1.  
          About Flexible Storage Sharing disk support
        2.  
          About the volume layout for Flexible Storage Sharing disk groups
        3.  
          Setting the host prefix
        4.  
          Exporting a disk for Flexible Storage Sharing
        5.  
          Setting the Flexible Storage Sharing attribute on a disk group
        6.  
          Using the host disk class and allocating storage
        7.  
          Administering mirrored volumes using vxassist
        8.  
          Displaying exported disks and network shared disk groups
        9.  
          Tuning LLT for memory and performance in FSS environments
        10. Backing up and restoring disk group configuration data
          1.  
            Backing up and restoring Flexible Storage Sharing disk group configuration data
      8. Administering SF Oracle RAC global clusters
        1.  
          About setting up a disaster recovery fire drill
        2. About configuring the fire drill service group using the Fire Drill Setup wizard
          1.  
            Running the fire drill setup wizard
          2.  
            About configuring local attributes in the fire drill service group
        3.  
          Verifying a successful fire drill
        4.  
          Scheduling a fire drill
        5.  
          Sample fire drill service group configuration
  2. Section II. Performance and troubleshooting
    1. Troubleshooting SF Oracle RAC
      1. About troubleshooting SF Oracle RAC
        1. Gathering information from an SF Oracle RAC cluster for support analysis
          1.  
            Gathering configuration information using SORT Data Collector
          2.  
            Gathering SF Oracle RAC information for support analysis
          3.  
            Gathering VCS information for support analysis
          4.  
            Gathering LLT and GAB information for support analysis
          5.  
            Gathering IMF information for support analysis
        2. SF Oracle RAC log files
          1.  
            Collecting important CVM logs
        3.  
          About SF Oracle RAC kernel and driver messages
        4. VCS message logging
          1.  
            GAB message logging
          2.  
            About debug log tags usage
          3.  
            Enabling debug logs for agents
          4.  
            Enabling debug logs for the VCS engine
          5.  
            Enabling debug logs for IMF
          6.  
            Message catalogs
      2.  
        Restarting the installer after a failed network connection
      3.  
        Installer cannot create UUID for the cluster
      4.  
        Troubleshooting SF Oracle RAC pre-installation check failures
      5.  
        Troubleshooting LLT health check warning messages
      6. Troubleshooting I/O fencing
        1.  
          SCSI reservation errors during bootup
        2.  
          The vxfentsthdw utility fails when SCSI TEST UNIT READY command fails
        3.  
          Node is unable to join cluster while another node is being ejected
        4.  
          System panics to prevent potential data corruption
        5.  
          Cluster ID on the I/O fencing key of coordinator disk does not match the local cluster's ID
        6. Fencing startup reports preexisting split-brain
          1.  
            Clearing preexisting split-brain condition
        7.  
          Registered keys are lost on the coordinator disks
        8.  
          Replacing defective disks when the cluster is offline
        9.  
          Troubleshooting I/O fencing health check warning messages
        10. Troubleshooting CP server
          1.  
            Troubleshooting issues related to the CP server service group
          2.  
            Checking the connectivity of CP server
        11. Troubleshooting server-based fencing on the SF Oracle RAC cluster nodes
          1.  
            Issues during fencing startup on SF Oracle RAC cluster nodes set up for server-based fencing
        12. Issues during online migration of coordination points
          1.  
            Vxfen service group activity after issuing the vxfenswap command
      7. Troubleshooting Cluster Volume Manager in SF Oracle RAC clusters
        1.  
          Restoring communication between host and disks after cable disconnection
        2.  
          Shared disk group cannot be imported in SF Oracle RAC cluster
        3.  
          Error importing shared disk groups in SF Oracle RAC cluster
        4.  
          Unable to start CVM in SF Oracle RAC cluster
        5.  
          CVM group is not online after adding a node to the SF Oracle RAC cluster
        6.  
          CVMVolDg not online even though CVMCluster is online in SF Oracle RAC cluster
        7.  
          Shared disks not visible in SF Oracle RAC cluster
      8. Troubleshooting CFS
        1.  
          Incorrect order in root user's <library> path
      9. Troubleshooting interconnects
        1.  
          Example entries for mandatory devices
      10. Troubleshooting Oracle
        1.  
          Error when starting an Oracle instance in SF Oracle RAC
        2.  
          Clearing Oracle group faults
        3.  
          Oracle log files show shutdown called even when not shutdown manually
        4.  
          DBCA fails while creating an Oracle RAC database
        5.  
          Oracle's clusterware processes fail to start
        6.  
          Oracle Clusterware fails after restart
        7.  
          Troubleshooting the Virtual IP (VIP) configuration in an SF Oracle RAC cluster
        8.  
          Troubleshooting Oracle Clusterware health check warning messages in SF Oracle RAC clusters
      11. Troubleshooting ODM in SF Oracle RAC clusters
        1.  
          File System configured incorrectly for ODM shuts down Oracle
      12.  
        Troubleshooting Flex ASM in SF Oracle RAC clusters
    2. Prevention and recovery strategies
      1.  
        Verification of GAB ports in SF Oracle RAC cluster
      2.  
        Examining GAB seed membership
      3.  
        Manual GAB membership seeding
      4.  
        Evaluating VCS I/O fencing ports
      5.  
        Verifying normal functioning of VCS I/O fencing
      6. Managing SCSI-3 PR keys in SF Oracle RAC cluster
        1.  
          Evaluating the number of SCSI-3 PR keys on a coordinator LUN, if there are multiple paths to the LUN from the hosts
        2.  
          Detecting accidental SCSI-3 PR key removal from coordinator LUNs
      7.  
        Identifying a faulty coordinator LUN
    3. Tunable parameters
      1.  
        About SF Oracle RAC tunable parameters
      2. About GAB tunable parameters
        1.  
          About GAB load-time or static tunable parameters
        2.  
          About GAB run-time or dynamic tunable parameters
      3. About LLT tunable parameters
        1.  
          About LLT timer tunable parameters
        2.  
          About LLT flow control tunable parameters
        3.  
          Setting LLT timer tunable parameters
      4. About VXFEN tunable parameters
        1.  
          Configuring the VXFEN module parameters
      5.  
        Tuning guidelines for campus clusters
  3. Section III. Reference
    1. Appendix A. List of SF Oracle RAC health checks
      1.  
        LLT health checks
      2.  
        I/O fencing health checks
      3.  
        PrivNIC health checks in SF Oracle RAC clusters
      4.  
        Oracle Clusterware health checks in SF Oracle RAC clusters
      5.  
        CVM, CFS, and ODM health checks in SF Oracle RAC clusters
    2. Appendix B. Error messages
      1.  
        About error messages
      2.  
        VxVM error messages
      3. VXFEN driver error messages
        1.  
          VXFEN driver informational message
        2.  
          Node ejection informational messages

About Low Latency Transport (LLT)

The Low Latency Transport protocol is used for all cluster communications as a high-performance, low-latency replacement for the IP stack.

LLT has the following two major functions:

  • Traffic distribution

    LLT provides the communications backbone for GAB. LLT distributes (load balances) inter-system communication across all configured network links. This distribution ensures all cluster communications are evenly distributed across all network links for performance and fault resilience. If a link fails, traffic is redirected to the remaining links. A maximum of eight network links are supported.

  • Heartbeat

    LLT is responsible for sending and receiving heartbeat traffic over each configured network link. The heartbeat traffic is point to point unicast. LLT uses ethernet broadcast to learn the address of the nodes in the cluster. All other cluster communications, including all status and configuration traffic is point to point unicast. The heartbeat is used by the Group Membership Services to determine cluster membership.

The heartbeat signal is defined as follows:

  • LLT on each system in the cluster sends heartbeat packets out on all configured LLT interfaces every half second.

  • LLT on each system tracks the heartbeat status from each peer on each configured LLT interface.

  • LLT on each system forwards the heartbeat status of each system in the cluster to the local Group Membership Services function of GAB.

  • GAB receives the status of heartbeat from all cluster systems from LLT and makes membership determination based on this information.

Figure: Heartbeat in the cluster shows heartbeat in the cluster.

Figure: Heartbeat in the cluster

Heartbeat in the cluster

LLT can be configured to designate specific cluster interconnect links as either high priority or low priority. High priority links are used for cluster communications to GAB as well as heartbeat signals. Low priority links, during normal operation, are used for heartbeat and link state maintenance only, and the frequency of heartbeats is reduced to 50% of normal to reduce network overhead.

If there is a failure of all configured high priority links, LLT will switch all cluster communications traffic to the first available low priority link. Communication traffic will revert back to the high priority links as soon as they become available.

While not required, best practice recommends to configure at least one low priority link, and to configure two high priority links on dedicated cluster interconnects to provide redundancy in the communications path. Low priority links are typically configured on the public or administrative network.

If you use different media speed for the private NICs, Veritas recommends that you configure the NICs with lesser speed as low-priority links to enhance LLT performance. With this setting, LLT does active-passive load balancing across the private links. At the time of configuration and failover, LLT automatically chooses the link with high-priority as the active link and uses the low-priority links only when a high-priority link fails.

LLT sends packets on all the configured links in weighted round-robin manner. LLT uses the linkburst parameter which represents the number of back-to-back packets that LLT sends on a link before the next link is chosen. In addition to the default weighted round-robin based load balancing, LLT also provides destination-based load balancing. LLT implements destination-based load balancing where the LLT link is chosen based on the destination node id and the port. With destination-based load balancing, LLT sends all the packets of a particular destination on a link. However, a potential problem with the destination-based load balancing approach is that LLT may not fully utilize the available links if the ports have dissimilar traffic. Veritas recommends destination-based load balancing when the setup has more than two cluster nodes and more active LLT ports. You must manually configure destination-based load balancing for your cluster to set up the port to LLT link mapping.

See Configuring destination-based load balancing for LLT.

LLT on startup sends broadcast packets with LLT node id and cluster id information onto the LAN to discover any node in the network that has same node id and cluster id pair. Each node in the network replies to this broadcast message with its cluster id, node id, and node name.

LLT on the original node does not start and gives appropriate error in the following cases:

  • LLT on any other node in the same network is running with the same node id and cluster id pair that it owns.

  • LLT on the original node receives response from a node that does not have a node name entry in the /etc/llthosts file.