Configuring I/O fencing to prevent data corruption

Perform the following tasks to configure I/O fencing to prevent data corruption in the event of a communication failure.

To configure I/O fencing to prevent data corruption

  1. After installing and configuring SFCFSHA or SF Oracle RAC, configure I/O fencing for data integrity.

    See the Storage Foundation Cluster File System High Availability Configuration and Upgrade Guide.

    See the Storage Foundation for Oracle RAC Configuration and Upgrade Guide.

  2. Set up the storage at a third site.

    You can extend the DWDM to the third site to have FC SAN connectivity to the storage at the third site. You can also use iSCSI targets as the coordinator disks at the third site.

    For example:

    Enable I/O fencing by using the coordinator disks from all the three sites.

    # vxdisksetup -i disk04 format=cdsdisk
    
    # vxdisksetup -i disk09 format=cdsdisk
    # vxdisksetup -i disk10 format=cdsdisk
    # hastop -all
    # vxdg init fencedg disk10 disk04 disk09
    # vxdg -g fencedg set coordinator=on
    # vxdg deport fencedg
    # vxdg -t import fencedg
    # vxdg deport fencedg

    Edit the main.cf to add "UseFence = SCSI3"

    # vi /etc/VRTSvcs/conf/config/main.cf
    # more /etc/vxfendg
    fencedg
    # more /etc/vxfentab
    /dev/vx/rdmp/disk10
    /dev/vx/rdmp/disk04
    /dev/vx/rdmp/disk09
    # cp /etc/vxfen.d/vxfenmode_scsi3_dmp /etc/vxfemode
    
    /etc/init.d/vxfen start
    Starting vxfen..
    Checking for /etc/vxfendg
    Starting vxfen.. Done

    On all nodes, start VCS:

    # hastart

    Set the site name for each host.

    # vxdctl set site=site1
    # vxdctl set site=site2
    # vxdctl set site=site3
    
  3. Start I/O fencing on all the sites.