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SC Series array and Oracle storage management

80 Dell EMC SC Series: Oracle Best Practices | CML1114

# grep emcpowerg1 /proc/partitions

120 97 52428784 emcpowerb1

ASM should also have access to all SCSI paths of the PowerPath partitioned pseudo-device:

# /etc/init.d/oracleasm querydisk -p DATA1

Disk "DATA1" is a valid ASM disk

/dev/sdc1: LABEL="DATA1" TYPE="oracleasm"

/dev/sdi1: LABEL="DATA1" TYPE="oracleasm"

/dev/sdac1: LABEL="DATA1" TYPE="oracleasm"

/dev/sdaf1: LABEL="DATA1" TYPE="oracleasm"

/dev/emcpowerb1: LABEL="DATA1" TYPE="oracleasm"

4. In a RAC environment, after all the ASM disks have been created, execute the following command on

the other nodes of the cluster:

/etc/init.d/oracleasm scandisks

For more information on using Dell EMC PowerPath with Oracle ASM see Using Oracle Database 10g’s

Automatic Storage Management with EMC Storage Technology, a joint engineering white paper authored by

Dell EMC and Oracle.

6.2.2 ASMLib and Linux DM-Multipath

After a partition is created on a DM-Multipath pseudo-device and the partition table updated, the DM-Multipath

partitioned pseudo-device is visible

# fdisk /dev/mapper/oraasm-data1

# partprobe /dev/mapper/oraasm-data1

# ls -ltr /dev/mapper/oraasm-data1p1

lrwxrwxrwx 1 root root 7 Apr 14 11:56 /dev/mapper/oraasm-data1p1 -> ../dm-13

To use the partitioned pseudo-device with ASMLib, use the following process:

1. For consistent and persistent device mappings of DM-Multipath devices, ASMLib must be configured

to only scan device-mapper devices (/dev/dm-<n>) before scanning other devices (e.g. the SCSI

devices.). Devices in /dev/mapper/<name> are created by UDEV for improved human readability

and are not known by the kernel. To only scan device-mapper devices, make sure

/etc/sysconfig/oracleasm contains the following ASMLib directive and value, then restart

ASMLib. If the environment is a RAC environment, add the directive to file oracleasm on all nodes of

the cluster. Then, restart ASMLib on all nodes of the cluster:

ORACLEASM_SCANORDER="dm-"

# /etc/init.d/oracleasm restart

Dropping Oracle ASMLib disks: [ OK ]

Shutting down the Oracle ASMLib driver: [ OK ]

Initializing the Oracle ASMLib driver: [ OK ]

Scanning the system for Oracle ASMLib disks: [ OK ]#