7 Replies Latest reply: Mar 21, 2014 12:30 AM by Simo Kemppinen RSS

    ASM Spfile

    user11153253

      Hi folks,

       

      we have 3 Nodes RAC Production database .

      Grid infrastructure is installed by user grid

      Database software is installed by user Oracle.

       

      so when i query on each instance for central spfile it showing me below and we have separate instance specific parameter file which is pointing to Central spfile or Pfile

       

      #su - oracle

      node1 $ cd $ORACLE_HOME/dbs

      $ls

      initebase1.ora

      $cat initebase.ora

      spfile=/+DATA1/EBASE/spfile.ora

       

      SQL>show parameter spfile;

      spfile=/+DATA1/EBASE/spfile.ora

       

      SQL>show parameter pfile;

      spfile=/+DATA1/EBASE/spfile.ora



      the same above  result comes on Node2, Node3

      But when i log in through  grid user like below

       

      #su - grid

      $cd $ORACLE_HOME/dbs

      $ls

       

      SQL>show parameter spfile;

      spfile=/OCRVD/clustername/registry./spfile.ora


      SQL>show parameter pfile;

      spfile=/OCRVD/clustername/registry./spfile.ora


      My questions is here


      1)is there  no instance specific ASM parameter file which points to Central spfile or pfile for ASM?

      2)Please clarify the above spfile=/OCRVD/clustername/registry./spfile.ora is my central  spfile for ASM. or not?



      thanks & Regards.

        • 1. Re: ASM Spfile
          J.A.

          Hi

          Each database use a spfile/pfile, in this RAC the Spfile is in the ASM, so each database instance can access the same spfile, this is correct.

           

          Also the ASM  has its own Spfile, normally in a RAC the ASM Spfile lives on the OCR/Voting disk DiskGroup, so each ASM instance can access the same Spfile, this is correct.

           

          I hope this help you

           

          Regards

          • 2. Re: ASM Spfile
            Simo Kemppinen

            Hi,

             

            For RAC installations there is single shared ASM spfile for all instances. If you want to see it you have to check it from ASM instance (run following in cluster first node):

            export ORACLE_HOME=<Your_Grid_Home>

            export ORACLE_SID=+ASM1

            sqlplus / as sysasm

             

            SQL> show parameter spfile;

             

            # To see what is inside the file do this:

            SQL> create pfile='/tmp/asmpfile.ora' from spfile;

            SQL> ! less /tmp/asmpfile.ora

             

            When you look the file you can notice that there is instance specific parameters.

            Like:

            +ASM1.__large_pool_size

            and

            +ASM2.__large_pool_size=16777216

             

            So the file is shared but inside it there is instance specific parameters.

             

            And if you checked this value from your ASM instance then it is your shared (central) spfile:

            spfile=/OCRVD/clustername/registry./spfile.ora

             

            Here you can find more specific info about ASM spfile:

            Administering Oracle ASM Instances

            • 3. Re: ASM Spfile
              user11153253

              Hi simo

               

              look out the outpout of spfile

               

              SQL> show parameter spfile;

              NAME                                 TYPE        VALUE

              ------------------------------------ ----------- ------------------------------

              spfile                               string      +OCVD/vserv-eppm-cs/asmparamet

                                                               erfile/registry.253.840038473

              SQL> ! less /tmp/asmpfile.ora

              +ASM1.asm_diskgroups='ARCH','DATA1'#Manual Mount

              +ASM2.asm_diskgroups='ARCH','DATA1'#Manual Mount

              *.asm_power_limit=1

              *.diagnostic_dest='/oracle/app/grid'

              *.instance_type='asm'

              *.large_pool_size=12M

              *.remote_login_passwordfile='EXCLUSIVE'

               

               

              [grid@vserv-EPPM-DB3 dbs]$ cd $ORACLE_HOME/dbs

              [grid@vserv-EPPM-DB3 dbs]$ ls

              ab_+ASM1.dat  hc_+ASM1.dat  init.ora  orapw+ASM

               

              Here where is my instance specific parameter or spfile which communicate to Central above spile ( +OCVD/vserv-eppm-cs/asmparameterfile/registry.253.840038473)?

               

               

               


              • 4. Re: ASM Spfile
                Simo Kemppinen

                Yes this is your shared spfile:

                 

                +OCVD/vserv-eppm-cs/asmparameterfile/registry.253.840038473

                 

                 

                It is in ASM diskgroup so if you want to check the path where it is you can use amscmd:

                 

                export ORACLE_HOME=<Your_Grid_Home>

                 

                export ORACLE_SID=+ASM1

                 

                 

                asmcmd

                 

                 

                ASMCMD> cd +OCVD/vserv-eppm-cs/asmparameterfile

                 

                ASMCMD> ls -l

                 

                 

                But remember that spfile is in binary mode so you cannot see inside it. But you can make pfile from spfile, like we did above, and then watch inside it.

                 

                And like I said with RAC there is no instance specific spfile only shared spfile. And inside that shared file there is common values for all instances and values for specific instances.

                • 6. Re: ASM Spfile
                  user11153253

                  Hi simo,

                   

                  thanks for your reply,

                  As you said there is no instance specific spfile or instance specific parameter. how much you sure about it, please confrim.me

                  thanks again for your sharing.

                   

                   

                  thanks $& regards

                  • 7. Re: ASM Spfile
                    Simo Kemppinen

                    This document confirms it:

                    Administering Oracle ASM Instances

                     

                    It says:

                    "When installing Oracle ASM in a clustered Oracle ASM environment, OUI creates a single, shared SPFILE for Oracle ASM in a disk group."