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4 Replies Latest reply: May 20, 2013 8:35 AM by AshishShukla RSS

OCR Redundancy - Can we have OCR Mirror with Redo logs in REDO01 diskgroup?

Azam Newbie
Currently Being Moderated
Hello,

I have 2 node Oracle 11gr2 (11.2.0.3) RAC on AIX 6.1. Currently there is only one OCR and one VD residing in OCRVD diskgroup which as external redundancy.

## STATE File Universal Id File Name Disk group
-- ----- ----------------- --------- ---------
1. ONLINE a27d6a5df2db4f31bf0c9c9d31870b1f (/dev/rhdisk11) [OCRVD]
Located 1 voting disk(s).


$ ocrcheck
Status of Oracle Cluster Registry is as follows :
Version : 3
Total space (kbytes) : 262120
Used space (kbytes) : 3152
Available space (kbytes) : 258968
ID : 899322289
Device/File Name : +OCRVD
Device/File integrity check succeeded

Device/File not configured

Device/File not configured

Device/File not configured

Device/File not configured

Cluster registry integrity check succeeded

Logical corruption check bypassed due to non-privileged user

OCRVD Diskgroup is created using 5 disks of size 1G with RAID 1.

1. Is it possible that I multiplex OCR and VD in the same diskgroup?
2. If it is not possible, then shall I add OCR and VD in other diskgroups (Eg: REDO01 and REDO02 - these are for Redo logs)?

Edited by: Azam on May 20, 2013 2:46 PM
  • 1. Re: OCR Redundancy - Can we have OCR Mirror with Redo logs in REDO01 diskgroup?
    MahirM.Quluzade Guru
    Currently Being Moderated
    Azam wrote:
    Hello,

    I have 2 node Oracle 11gr2 (11.2.0.3) RAC on AIX 6.1. Currently there is only one OCR and one VD residing in OCRVD diskgroup which as external redundancy.

    ## STATE File Universal Id File Name Disk group
    -- ----- ----------------- --------- ---------
    1. ONLINE a27d6a5df2db4f31bf0c9c9d31870b1f (/dev/rhdisk11) [OCRVD]
    Located 1 voting disk(s).


    $ ocrcheck
    Status of Oracle Cluster Registry is as follows :
    Version : 3
    Total space (kbytes) : 262120
    Used space (kbytes) : 3152
    Available space (kbytes) : 258968
    ID : 899322289
    Device/File Name : +OCRVD
    Device/File integrity check succeeded

    Device/File not configured

    Device/File not configured

    Device/File not configured

    Device/File not configured

    Cluster registry integrity check succeeded

    Logical corruption check bypassed due to non-privileged user

    OCRVD Diskgroup is created using 5 disks of size 1G with RAID 1.

    1. Is it possible that I multiplex OCR and VD in the same diskgroup?
    No, it is no posible
    2. If it is not possible, then shall I add OCR and VD in other diskgroups (Eg: REDO01 and REDO02 - these are for Redo logs)?
    Yes you can add other diskgroups. As the root user, run the following command to add an OCR location to either Oracle ASM
    ocrconfig -add +REDO01
    ocrconfig -add +REDO02
    As you know mirroring on ASM level between ASM disks which is contains in ASM DISKGROUP.


    Regards
    Mahir M. Quluzade
  • 2. Re: OCR Redundancy - Can we have OCR Mirror with Redo logs in REDO01 diskgroup?
    rarain Explorer
    Currently Being Moderated
    Hi,

    With OCR you can also move voting disk from one diskgroup to another diskgroup online and based on the redundancy of the diskgroup number of voting disks will be configured.

    # crsctl replace votedisk <+DISKGROUP_NAME>

    External-> one voting disk
    Normal -> Three voting disk
    High -> Five Voting disk

    Thanks
  • 3. Re: OCR Redundancy - Can we have OCR Mirror with Redo logs in REDO01 diskgroup?
    MahirM.Quluzade Guru
    Currently Being Moderated
    rarain wrote:
    Hi,

    With OCR you can also move voting disk from one diskgroup to another diskgroup online and based on the redundancy of the diskgroup number of voting disks will be configured.

    # crsctl replace votedisk <+DISKGROUP_NAME>

    External-> one voting disk
    Normal -> Three voting disk
    High -> Five Voting disk

    Thanks
    Oracle recommended : High Redundancy disk groups for OCR and VOTE disk. Only for OCR Normal Redundancy must be with 3 and High is must be 5 Fail group.
    If you are using disk groups for normal data (non OCR). Normal redundancy 2 way mirroring, and High redundancy is 3 way mirroring.

    Regards
    Mahir M. Quluzade
  • 4. Re: OCR Redundancy - Can we have OCR Mirror with Redo logs in REDO01 diskgroup?
    AshishShukla Newbie
    Currently Being Moderated
    Hello Azam,


    First of all answer for your question is YES.

    One of the new feature of 11.2 RAC is, now we can store OCR & VOTING disk both on ASM. Even if you want you can store both OCR & Voting disk on the same diskgroup.

    Please not that ASM does striping for OCR file but it keeps voting file as it is without doing striping.
    In my case My OCR & VOTING disks are on +DATA diskgroup.

    [grid@host01 ~]$ crsctl query css votedisk

    ## STATE File Universal Id File Name Disk group
    -- ----- ----------------- --------- ---------
    1. ONLINE 43b81ce42d9d4f9bbfcc3914003d5ac9 (ORCL:ASMDISK01) *[DATA]*
    2. ONLINE 38e71bedf4174f24bfa7ee6ab48ef858 (ORCL:ASMDISK02) *[DATA]*
    3. ONLINE 026cb26c84424f49bf130480562ab3f1 (ORCL:ASMDISK03) *[DATA]*
    Located 3 voting disk(s).

    [root@host01 ~]# ocrcheck
    Status of Oracle Cluster Registry is as follows :
    Version : 3
    Total space (kbytes) : 262120
    Used space (kbytes) : 3584
    Available space (kbytes) : 258536
    ID : 456262459
    Device/File Name : +DATA*

    ASM does striping for OCR that you can verify from this output:

    ASMCMD> lstmpl -G DATA -l
    Group_Name Group_Num Name      Stripe           Sys Redund      PriReg MirrReg
    DATA 2 ARCHIVELOG           COARSE      Y MIRROR      COLD COLD
    DATA 2 ASMPARAMETERBAKFILE      COARSE      Y MIRROR      COLD COLD
    DATA 2 ASMPARAMETERFILE      COARSE      Y MIRROR      COLD COLD
    DATA 2 ASM_STALE           COARSE      Y HIGH      COLD COLD
    DATA 2 AUTOBACKUP           COARSE      Y MIRROR      COLD COLD
    DATA 2 BACKUPSET           COARSE      Y MIRROR      COLD COLD
    DATA 2 CHANGETRACKING      COARSE      Y MIRROR      COLD COLD
    DATA 2 CONTROLFILE      FINE      Y HIGH      COLD COLD
    DATA 2 DATAFILE           COARSE      Y MIRROR      COLD COLD
    DATA 2 DATAGUARDCONFIG      COARSE      Y MIRROR      COLD COLD
    DATA 2 DUMPSET           COARSE      Y MIRROR      COLD COLD
    DATA 2 FLASHBACK           COARSE      Y MIRROR      COLD COLD
    DATA 2 FLASHFILE           COARSE      Y MIRROR      COLD COLD
    DATA 2 OCRBACKUP           COARSE      Y MIRROR      COLD COLD
    DATA        2          OCRFILE                        COARSE       Y    MIRROR       COLD    COLD
    DATA 2 ONLINELOG           COARSE      Y MIRROR      COLD COLD
    DATA 2 PARAMETERFILE      COARSE      Y MIRROR      COLD COLD
    DATA 2 TEMPFILE           COARSE      Y MIRROR      COLD COLD
    DATA 2 XTRANSPORT      COARSE      Y MIRROR      COLD COLD


    Even if you want you can store OCR in one diskgroup and VOTING in another diskgroup. But remember if you are planning to store VOTING disk on any ASM diskgroup then number VOTING disk depend on the redundancy level of the ASM diskgroup.
    e.g:
    diskgroup with,
    External Redundancy     :      One VOTING DISK
    Normal Redundancy     :      Three VOTING DISKS
    High Redundancy     :      Five VOTING DISKS

    Now if you want to move your OCR disks to any other diskgroup, then:

    [root@host01 ~]# *ocrconfig -add +TEST*

    [root@host01 ~]# ocrcheck
    Status of Oracle Cluster Registry is as follows :
    Version : 3
    Total space (kbytes) : 262120
    Used space (kbytes) : 3584
    Available space (kbytes) : 258536
    ID : 456262459
    *Device/File Name         :      +DATA*
    Device/File integrity check succeeded
    *Device/File Name         :      +TEST*
    Device/File integrity check succeeded


    [root@host01 ~]# *ocrconfig -delete +DATA*
    [root@host01 ~]# ocrcheck
    Status of Oracle Cluster Registry is as follows :
    Version : 3
    Total space (kbytes) : 262120
    Used space (kbytes) : 3584
    Available space (kbytes) : 258536
    ID : 456262459
    *Device/File Name         :      +TEST*
    Device/File integrity check succeeded




    Thanks,
    Ashish Shukla

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