RHEL5 uses multipath to configure ASMdisk

Fdisk view disk [root @ db11g ~] # Catetcredhat-releaseRedHatEnterpriseLinuxServerrelease5.9 (Tikanga) [root @ db11g ~] # [Root @ db11g ~] # [Root @ db11g ~] # Fdisk-lDiskdevsda: 32.2 GB, 32212254720bytes255heads, 63 sectorstrack, 3916c

Fdisk view disk [root @ db11g ~] # Cat/etc/redhat-release Red Hat Enterprise Linux Server release 5.9 (Tikanga) [root @ db11g ~] # [Root @ db11g ~] # [Root @ db11g ~] # Fdisk-lDisk/dev/sda: 32.2 GB, 32212254720 bytes255 heads, 63 sectors/track, 3916 c

Fdisk view disk

[root@db11g ~]# cat /etc/redhat-release Red Hat Enterprise Linux Server release 5.9 (Tikanga)[root@db11g ~]# [root@db11g ~]# [root@db11g ~]# fdisk -lDisk /dev/sda: 32.2 GB, 32212254720 bytes255 heads, 63 sectors/track, 3916 cylindersUnits = cylinders of 16065 * 512 = 8225280 bytes   Device Boot      Start         End      Blocks   Id  System/dev/sda1   *           1          13      104391   83  Linux/dev/sda2              14        3916    31350847+  8e  Linux LVMDisk /dev/sdb: 17.1 GB, 17179869184 bytes255 heads, 63 sectors/track, 2088 cylindersUnits = cylinders of 16065 * 512 = 8225280 bytesDisk /dev/sdb doesn't contain a valid partition tableDisk /dev/sdc: 10.7 GB, 10737418240 bytes255 heads, 63 sectors/track, 1305 cylindersUnits = cylinders of 16065 * 512 = 8225280 bytesDisk /dev/sdc doesn't contain a valid partition table

Obtain the scsi id

[root@db11g ~]# /sbin/scsi_id -g -u -s /block/sdbSATA_VBOX_HARDDISK_VB3c0bb909-10aab3a0_[root@db11g ~]# /sbin/scsi_id -g -u -s /block/sdcSATA_VBOX_HARDDISK_VB3edd7dc1-fd831bf4_

Run the following command in RHEL6:

scsi_id --whitelisted --replace-whitespace –-device=/dev/sdb

Install the multipath rpm package

[root@db11g ~]# yum install device-mapper*Loaded plugins: rhnplugin, securityThis system is not registered with ULN.You can use up2date --register to register.ULN support will be disabled.Setting up Install ProcessPackage device-mapper-multipath-0.4.9-56.0.3.el5.x86_64 already installed and latest versionPackage device-mapper-multipath-libs-0.4.9-56.0.3.el5.x86_64 already installed and latest versionPackage device-mapper-event-1.02.67-2.el5.x86_64 already installed and latest versionPackage device-mapper-1.02.67-2.el5.x86_64 already installed and latest versionPackage device-mapper-1.02.67-2.el5.i386 already installed and latest versionNothing to do[root@db11g ~]# [root@db11g ~]# [root@db11g ~]# [root@db11g ~]# [root@db11g ~]# rpm -qa|grep device-mapperdevice-mapper-multipath-libs-0.4.9-56.0.3.el5device-mapper-event-1.02.67-2.el5device-mapper-1.02.67-2.el5device-mapper-1.02.67-2.el5device-mapper-multipath-0.4.9-56.0.3.el5

Obtain the uid and gid of the grid user. The gid here is the gid of the asmadmin group.

[root@db11g ~]# cat /etc/passwd|grep gridgrid:x:1100:1000:Grid Infrastructure Owner:/home/grid:/bin/bash[root@db11g ~]# cat /etc/group|grep asmadminasmadmin:x:1200:grid,oracle[root@db11g ~]# id -a griduid=1100(grid) gid=1000(oinstall) groups=1000(oinstall),1200(asmadmin),1201(asmdba),1202(asmoper),1300(dba)

Configure/etc/multipath. conf

[root@db11g ~]# cp /usr/share/doc/device-mapper-multipath-0.4.9/multipath.conf /etc/[root@db11g ~]# cat /etc/multipath.confdefaults {user_friendly_names noqueue_without_daemon noflush_on_last_del yesmax_fds max} blacklist {devnode "^hd[a-z]"devnode "^(ram|raw|loop|fd|md|dm-|sr|scd|st)[0-9]*"devnode "^cciss.*"} devices {        device {                vendor                  "OPNFILER "                product                 "LUN"                path_grouping_policy    group_by_prio                features                "3 queue_if_no_path pg_init_retries 50"                getuid_callout          "/sbin/scsi_id -g -u -s /block/%n"                path_checker            tur                path_selector           "round-robin 0"                hardware_handler        "1 alua"                failback                immediate                rr_weight               uniform                rr_min_io               128        }} multipaths {        multipath {                wwid                    SATA_VBOX_HARDDISK_VB3c0bb909-10aab3a0_                 alias                   datadisk                uid                     1100                                                               gid                     1200                                                      }           multipath {                wwid                    SATA_VBOX_HARDDISK_VB3edd7dc1-fd831bf4_                   alias                   fradisk                                                          uid                     1100                                                               gid                     1200                                                        }}

Start multipath

[root@db11g ~]# modprobe dm-multipath[root@db11g ~]# modprobe dm-round-robin[root@db11g ~]# chkconfig multipathd start[root@db11g ~]# chkconfig multipathd on[root@db11g ~]# /etc/init.d/multipathd startStarting multipathd daemon: [  OK  ][root@db11g ~]# ps -ef|grep multipathdroot      3084     1  0 13:16 ?        00:00:00 /sbin/multipathdroot      3186  2877  0 13:16 pts/0    00:00:00 grep multipathd[root@db11g ~]# multipath -F[root@db11g ~]# multipath -v2Jan 15 13:17:40 | SATA_VBOX_HARDDISK_VBa64c2685-cc2f3dd0_: ignoring mapcreate: datadisk (SATA_VBOX_HARDDISK_VB3c0bb909-10aab3a0_) undef ATA,VBOX HARDDISKsize=16G features='0' hwhandler='0' wp=undef`-+- policy='round-robin 0' prio=1 status=undef  `- 1:0:0:0 sdb 8:16 undef ready runningcreate: fradisk (SATA_VBOX_HARDDISK_VB3edd7dc1-fd831bf4_) undef ATA,VBOX HARDDISKsize=10G features='0' hwhandler='0' wp=undef`-+- policy='round-robin 0' prio=1 status=undef  `- 2:0:0:0 sdc 8:32 undef ready running[root@db11g ~]# [root@db11g ~]# multipath -llfradisk (SATA_VBOX_HARDDISK_VB3edd7dc1-fd831bf4_) dm-3 ATA,VBOX HARDDISKsize=10G features='0' hwhandler='0' wp=rw`-+- policy='round-robin 0' prio=1 status=active  `- 2:0:0:0 sdc 8:32 active ready runningdatadisk (SATA_VBOX_HARDDISK_VB3c0bb909-10aab3a0_) dm-2 ATA,VBOX HARDDISKsize=16G features='0' hwhandler='0' wp=rw`-+- policy='round-robin 0' prio=1 status=active  `- 1:0:0:0 sdb 8:16 active ready running

[root@db11g ~]# ll /dev/mapper/*diskbrw-rw---- 1 grid asmadmin 252, 2 Jan 15 13:17 /dev/mapper/datadiskbrw-rw---- 1 grid asmadmin 252, 3 Jan 15 13:17 /dev/mapper/fradisk