1 Reply Latest reply: Mar 4, 2014 1:43 AM by Aritra-Oracle RSS

    ASM diskgroups automatic mounting when a RAC node is booted

    1007321

      Hello,

       

      We're on RAC in 11g on RH 6 on Dell with EqualLogic storage. Using ASMLib.

      When installing the Grid infrastructure I left many things to defaults and ended up with:

       

      o spfile parameter in +ASM1/2 instances is null;

       

      o when dumping this spfile to a text pfile, I read the following:

      ~ +ASM1.asm_diskgroups='ARCH1','REDO1','FRA1','STBYREDO'#Manual Mount

      ~ +ASM2.asm_diskgroups='ARCH1','FRA1','REDO1','STBYREDO'#Manual Mount

      ~ *.asm_diskgroups='ARCH1','REDO1','FRA1','STBYREDO','DATA1'     [<= here ALL my diskgroups are present !]

      ~ *.asm_diskstring='/dev/oracleasm/disks'

       

      My questions:

      1/ should I modify spfile parameter explicitly to the path I find in ASMCMD ??

      (which is: should I do an "ALTER SYSTEM SET spfile='+DATA1/cluname/ASMPARAMETERFILE/REGISTRY.243.847143025' scope=both") ??

       

      Regarding my asm_disk* parameters:

      2/ when doing a "show parameter asm_disktring" (or a SELECT FROM gv$parameter) it is null, and the

      doc says "The default value of the ASM_DISKSTRING parameter is a NULL string", which is what I have, then:

      a) if I have no +ASM*.asm_diskstring parameter listed in my pfile indeed, how come I find a *.asm_diskstring with the good value ?

      b) should I modify this parameter and do an explicit ALTER SYSTEM asm_diskstring to set it to '/dev/oracleasm/disks' ??

       

      3/ asm_diskgroups only contain ARCH1, REDO1, FRA1 and STBYREDO: DATA1 is missing, therefore should I modify

      this parameter and do an explicit ALTER SYSTEM asm_diskgroups to set it to 'ARCH1','REDO1','FRA1','STBYREDO','DATA1' ??

      What is best practice here ?

       

      4/ what is this "#Manual Mount" comment, where does it come from ?

       

      In advance, thanks.

      Regards,

      Seb

        • 1. Re: ASM diskgroups automatic mounting when a RAC node is booted
          Aritra-Oracle

          Hi Seb,    

           

           

          We're on RAC in 11g on RH 6 on Dell with EqualLogic storage. Using ASMLib.

          When installing the Grid infrastructure I left many things to defaults and ended up with:

           

          o spfile parameter in +ASM1/2 instances is null;

           

          o when dumping this spfile to a text pfile, I read the following:

          ~ +ASM1.asm_diskgroups='ARCH1','REDO1','FRA1','STBYREDO'#Manual Mount

          ~ +ASM2.asm_diskgroups='ARCH1','FRA1','REDO1','STBYREDO'#Manual Mount

          ~ *.asm_diskgroups='ARCH1','REDO1','FRA1','STBYREDO','DATA1'     [<= here ALL my diskgroups are present !]

          ~ *.asm_diskstring='/dev/oracleasm/disks'

           

          My questions:

          1/ should I modify spfile parameter explicitly to the path I find in ASMCMD ??

          (which is: should I do an "ALTER SYSTEM SET spfile='+DATA1/cluname/ASMPARAMETERFILE/REGISTRY.243.847143025' scope=both") ??

           

           

          ==>> You can use amscmd spset command is you have ASM spfile,

           

           

          example,

           

           

          $ asmcmd

          ASMCMD> spset +DATA/stgrac-cluster/asmparameterfile/registry.253.821440401

          ASMCMD>

           

           

           

          Regarding my asm_disk* parameters:

          2/ when doing a "show parameter asm_disktring" (or a SELECT FROM gv$parameter) it is null, and the

          doc says "The default value of the ASM_DISKSTRING parameter is a NULL string", which is what I have, then:

          a) if I have no +ASM*.asm_diskstring parameter listed in my pfile indeed, how come I find a *.asm_diskstring with the good value ?

           

           

          ==>> If you are using ASMlib in your system ,and asm_diskstring is NULL ,means it is actually using ASMlib through ORCL:* path.

               From v$asm_disk view you can see it is using ASMLib API.

            

            So,no need to change this value.

            

          b) should I modify this parameter and do an explicit ALTER SYSTEM asm_diskstring to set it to '/dev/oracleasm/disks' ??

           

           

          ===>> If you use this path ,then ASM will not use ASMlib API ,rather it will use system calls to access those devices .

           

          3/ asm_diskgroups only contain ARCH1, REDO1, FRA1 and STBYREDO: DATA1 is missing, therefore should I modify

          this parameter and do an explicit ALTER SYSTEM asm_diskgroups to set it to 'ARCH1','REDO1','FRA1','STBYREDO','DATA1' ??

          What is best practice here ?

           

          ==>>It seems DATA is holding spfile ,even if you do not add it ,ASM will pull up this diskgroup .

              If you want ,you can add it on asm_diskgroups parameter of ASM.

           

           

           

          4/ what is this "#Manual Mount" comment, where does it come from ?

           

           

          ==>> Validate if you have any pfile of ASM is available on dbs directory on this system of ASM_HOME .

           

           

          Regards,

          Aritra