How to Enabling and Diabling VxDMP devices for use with Oracle ASM

Enable DMP support for ASM to make DMP devices visible to ASM as available disks

To make DMP devices visible to ASM

1. From ASM, make sure ASM_DISKSTRING is set to the value/dev/raw/*.

   For Linux:

   The value for ASM_DISKSTRING is /dev/raw/*.

   SQL> show parameter ASM_DISKSTRING;
   	NAME                 TYPE        VALUE
   	-------------------- ----------- ---------------
   	asm_diskstring       string      /dev/raw/*

   For AIX, HP-UX, and Solaris:

   The value for ASM_DISKSTRING is /dev/vx/rdmp/*.

   SQL> show parameter ASM_DISKSTRING;
   	NAME                 TYPE        VALUE
   	-------------------- ----------- ---------------
   	asm_diskstring       string      /dev/vx/rdmp/*

2. As root user, enable DMP devices for use with ASM.

   # vxdmpraw enable usernamegroupname [devicename ...]

   For example:

   # vxdmpraw enable oracle dba eva4k6k0_1

3. For Linux, perform this step:

   The vxdmpraw enable command creates raw devices in the /dev/raw/* directory, corresponding to the DMP devices. Query the raw devices for devices with major number 201 and minor number between 241 to 255. There are 16 entries, since disks in Linux can have a maximum of 16 partitions. For example:

   # raw -qa | grep "major 201, minor 241"
   /dev/raw/raw54:  bound to major 201, minor 241

   The above output indicates that /dev/raw/raw54 corresponds to the partition/dev/vx/rdmp/eva4k6k0_1s1. Similarly, /dev/raw/raw55 corresponds to/dev/vx/rdmp/eva4k6k0_1s2 and so forth. Finally, /dev/raw/raw69 corresponds to/dev/vx/rdmp/eva4k6k0_1s15.

4. From ASM, confirm that ASM can see these new devices.

   SQL> select name,path,header_status from v$asm_disk;

   Sample output for Linux:

   NAME  PATH	                     HEADER_STATUS
   ---------------------------------------------
   ...   .......                   ....
         /dev/raw/raw53	           CANDIDATE
   ...  	.......   	               ....

   Sample output for AIX, HP-UX, and Solaris:

   NAME  PATH	                     HEADER_STATUS
   ---------------------------------------------
   ...   .......                   ....
        	/dev/vx/rdmp/eva4k6k0_1	  CANDIDATE
   ...  	.......   	               ....

Remove DMP devices from the listing of ASM disks

To remove DMP devices from the listing of ASM disks, disable DMP support for ASM from the device. You cannot remove DMP support for ASM from a device that is in an ASM disk group.

To remove the DMP device from the listing of ASM disks

1. If the device is part of any ASM disk group, remove the device from the ASM disk group.

2. As root user, disable DMP devices for use with ASM.

   # vxdmpraw disable diskname

   For example:

   # vxdmpraw disable eva4k6k0_1