Dynamic Multi-Pathing 7.3.1 Administrator's Guide - Linux
- Understanding DMP
- Setting up DMP to manage native devices
- Using Dynamic Multi-Pathing (DMP) devices with Oracle Automatic Storage Management (ASM)
- Administering DMP
- Administering DMP using the vxdmpadm utility
- Gathering and displaying I/O statistics
- Specifying the I/O policy
- Administering disks
- Discovering and configuring newly added disk devices
- About discovering disks and dynamically adding disk arrays
- How to administer the Device Discovery Layer
- Changing the disk device naming scheme
- Dynamic Reconfiguration of devices
- Reconfiguring a LUN online that is under DMP control using the Dynamic Reconfiguration tool
- Manually reconfiguring a LUN online that is under DMP control
- Event monitoring
- Performance monitoring and tuning
- Appendix A. DMP troubleshooting
- Appendix B. Reference
Enabling Dynamic Multi-Pathing (DMP) devices for use with Oracle Automatic Storage Management (ASM)
Enable DMP support for Oracle Automatic Storage Management (ASM) to make DMP devices visible to ASM as available disks. DMP support for ASM is available for char devices (/dev/vx/rdmp/*
).
To make DMP devices visible to ASM
- From ASM, make sure ASM_DISKSTRING is set to the correct value:
/dev/vx/rdmp/*
For example:
SQL> show parameter ASM_DISKSTRING; NAME TYPE VALUE -------------------- ----------- --------------- asm_diskstring string /dev/vx/rdmp/*
- As root user, enable DMP devices for use with ASM.
# vxdmpraw enable username groupname mode [devicename ...]
where username represents the ASM user running the ASM instance, groupname represents the UNIX/Linux groupname of the specified user-id, and mode represents the permissions to set on the device. If you specify one or more devicenames, DMP support for ASM is enabled for those devices. If you do not specify a devicename, DMP support is enabled for all devices in the system that have an ASM signature.
For example:
# vxdmpraw enable oracle dba 765 eva4k6k0_1
ASM support is enabled. The access permissions for the DMP device are set to the permissions specified by mode. The changes are persistent across reboots.
- From ASM, confirm that ASM can see these new devices.
SQL> select name,path,header_status from v$asm_disk;
NAME PATH HEADER_STATUS --------------------------------------------- ... ....... .... /dev/vx/rdmp/eva4k6k0_1 CANDIDATE ... ....... ....
- From ASM, increase the Oracle heartbeat wait time from the default value of 15 seconds. To prevent the Oracle application from marking the disk as offline during the DMP failover, increase the default value for _asm_hbeatiowait.
For example, to set the value to 360 seconds:
SQL> alter system set "_asm_hbeatiowait"=360 scope=spfile sid='*';
Restart the ASM instance for the new parameter to take effect.