HP UX Serviceguard Storage Management Software manual Command Failures, Performance Issues

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Troubleshooting

Cluster File System Problems

mount: slow

The node may be in the process of joining the cluster.

If you try to mount a file system that is already mounted onto another cluster node, without the -ocluster option, (that is, not in shared mode), for example:

#mount -F vxfs /dev/vx/dsk/share/vol01 /vol01

The following error message displays:

vxfs mount: /dev/vx/dsk/share/vol01 is already mounted, /vol01 is busy, allowable number of mount points exceeded, or cluster reservation failed for the volume

Command Failures

Manual pages not accessible with the man command. Set the MANPATH environment variable to include the path to the Veritas manual pages.

The mount, fsck, and mkfs utilities reserve a shared volume. They fail on volumes that are in use. Be careful when accessing shared volumes with other utilities such as dd, it is possible for these commands to destroy data on the disk.

Running some commands, such as vxupgrade -n 7/vol02, can generate the following error message:

vxfs vxupgrade: ERROR: not primary in a cluster file system

This means that you can run this command only on the primary, that is, the system that mounted this file system first.

Performance Issues

Quick I/O File system performance is adversely affected if a cluster file system is mounted with the qio option enabled and Quick I/O is licensed, but the file system is not used for Quick I/O files. Because qio is enabled by default, if you do not intend to use a shared file system for Quick I/O, explicitly specify the noqio option when mounting.

High Availability Issues

Low Memory

Under heavy loads, software that manages heartbeat communication links may not be able to allocate kernel memory. If this occurs, a node halts to avoid any chance of network partitioning. Reduce the load on the node if this happens frequently.

A similar situation may occur if the values in the /etc/llttab files on all cluster nodes are not correct or identical.

Appendix A

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Contents Second Edition Legal Notices Contents Troubleshooting Cluster Volume Manager AdministrationPrinting History Printing HistoryPage Technical Overview Group Lock Manager Overview of Cluster File System ArchitectureCluster File System Design Cluster File System FailoverSupported Features CFS Supported FeaturesVxFS Functionality on Cluster File Systems CFS Unsupported Features Unsupported FeaturesCFS Unsupported Features Benefits and Applications Advantages To Using CFSWhen To Use CFS Benefits and Applications Chapter Cluster File System Architecture Membership Ports Veritas Cluster Volume Manager FunctionalityRole of Component Products Cluster CommunicationAbout CFS Cluster File System and The Group Lock ManagerAsymmetric Mounts Primary and Secondary Mount Options Parallel I/OCluster File System Backup Strategies File System Tuneables Error Handling PolicySynchronizing Time on Cluster File Systems Distributing Load on a ClusterExample of a Four-Node Cluster About Veritas Cluster Volume Manager FunctionalityPrivate and Shared Disk Groups Activation Modes for Shared Disk Groups Activation Modes for Shared Disk GroupsAllowed and conflicting activation modes Connectivity Policy of Shared Disk GroupsLimitations of Shared Disk Groups About Veritas Cluster Volume Manager Functionality Chapter Cluster File System Administration Cluster File System Administration Cluster Messaging GAB Cluster Communication LLT Volume Manager Cluster Functionality Overview Cluster and Shared Mounts Cluster File System OverviewAsymmetric Mounts Cluster File System Commands Cluster File System AdministrationDistributing the Load on a Cluster Time Synchronization for Cluster File SystemsGrowing a Cluster File System Fstab fileCluster File System Administration Creating a Snapshot on a Cluster File System Cluster Snapshot CharacteristicsSnapshots for Cluster File Systems Performance Considerations# cfsumount /mnt1snap Cluster Volume Manager Overview of Cluster Volume Management Example of a 4-Node Cluster Disk group activation mode restrictions Either of the write modes on other nodes will fail # cfsdgadm display Behavior of Master Node for Different Failure Policies Disk Group Failure PolicyRecovery in a CVM Environment Troubleshooting Resource Temporarily Unavailable Installation IssuesInaccessible System Incorrect Permissions for Root on Remote SystemInstallation Issues Cluster File System Problems Unmount FailuresMount Failures Command Failures Performance IssuesHigh Availability Issues Cluster File System Problems Appendix a