RHEL 7.2使用EMC Powerpath扩容2T磁盘空间，需要添加至以用12C RAC for ASM系统中。下面是具体步骤，主机人员告知扩容别名为data_center_16、data_center_17

1：linux 7 系统下添加映射存储LUN(无需重启)
1>查看机器HBA卡信息--两个节点机器都得root用户执行
#ls /sys/class/fc_host
host0-10
2>通过修改文件“scan”权限，让系统重新扫描新的硬件设备
echo '- - -' > /sys/class/scsi_host/host0/scan
echo '- - -' > /sys/class/scsi_host/host1/scan
echo '- - -' > /sys/class/scsi_host/host2/scan
echo '- - -' > /sys/class/scsi_host/host3/scan
echo '- - -' > /sys/class/scsi_host/host4/scan
echo '- - -' > /sys/class/scsi_host/host5/scan
echo '- - -' > /sys/class/scsi_host/host6/scan
echo '- - -' > /sys/class/scsi_host/host7/scan
echo '- - -' > /sys/class/scsi_host/host8/scan
echo '- - -' > /sys/class/scsi_host/host9/scan
echo '- - -' > /sys/class/scsi_host/host10/scan

3>查询新识别出的来设备，两个节点机器都得执行root用户
#powermt display dev=all
#ls -al /dev/emcpower*
#powermt display
#powermt config
#powermt save

4>查询新增的扩容盘为data_center_16、data_center_17
Pseudo name=emcpowert
VNX ID=CKM00141100044 [data_center]
Logical device ID=60060160F7303500ACF6E88706A1E811 [data_center_16]
state=alive; policy=CLAROpt; queued-IOs=0
Owner: default=SP B, current=SP B Array failover mode: 4

==============================================================================
--------------- Host --------------- - Stor - -- I/O Path -- -- Stats ---

HW Path I/O Paths Interf. Mode State Q-IOs Errors

==============================================================================
9 lpfc sdcx SP B0 active alive 0 0
9 lpfc sdcv SP A1 active alive 0 0
1 lpfc sdct SP A0 active alive 0 0
1 lpfc sdcr SP B1 active alive 0 0

Pseudo name=emcpoweru
VNX ID=CKM00141100044 [data_center]
Logical device ID=60060160F7303500ADF6E88706A1E811 [data_center_17]
state=alive; policy=CLAROpt; queued-IOs=0
Owner: default=SP B, current=SP B Array failover mode: 4

--------------- Host --------------- - Stor - -- I/O Path -- -- Stats ---

HW Path I/O Paths Interf. Mode State Q-IOs Errors

==============================================================================
9 lpfc sdcy SP B0 active alive 0 0
9 lpfc sdcw SP A1 active alive 0 0
1 lpfc sdcu SP A0 active alive 0 0
1 lpfc sdcs SP B1 active alive 0 0

并且查看有关系统信息是否有emcpowert、emcpoweru此次扩容盘别名
cat /proc/partitions | awk {'print $4'} |grep emcpower|sort

5> 执行root下脚本asm_udev_ol7.sh

[root@dwdb1 ~]# more asm_udev_ol7.sh
#!/bin/bash
for i in $(cat /proc/partitions | awk {'print $4'} |grep emcpower|sort);
do
echo "ACTION==\"add|change\", KERNEL==\"emcpower*\", ENV{DEVTYPE}==\"disk\",SUBSYSTEM==\"block\", PROGRAM==\"
/usr/lib/udev/scsi_id -g -u -d --whitelisted --replace-whitespace --device=\$devnode\", RESULT==\"/usr/lib/u<br/>dev/scsi_id -g -u -d --whitelisted --replace-whitespace --device=/dev/$i\",RUN+=\"/bin/sh -c 'mknod /dev/asm
-$i b \$major \$minor; chown grid:asmadmin /dev/asm-$i; chmod 0660 /dev/asm-$i'\"" >> /etc/udev/rules.d/
99-oracle-asmdevices.rules_bak
done

6>生成的/etc/udev/rules.d/99-oracle-asmdevices.rules_bak中取出（360060160f7303500acf6e88706a1）
ACTION=="add|change", KERNEL=="emcpower", ENV{DEVTYPE}=="disk",SUBSYSTEM=="block", PROGRAM=="/usr/lib/udev/s
csi_id -g -u -d --whitelisted --replace-whitespace --device=$devnode", RESULT=="360060160f7303500acf6e88706a1
e811",RUN+="/bin/sh -c 'mknod /dev/asm-emcpowert b $major $minor; chown grid:asmadmin /dev/asm-emcpowert; chm
od 0660 /dev/asm-emcpowert'"
ACTION=="add|change", KERNEL=="emcpower", ENV{DEVTYPE}=="disk",SUBSYSTEM=="block", PROGRAM=="/usr/lib/udev/s
csi_id -g -u -d --whitelisted --replace-whitespace --device=$devnode", RESULT=="360060160f7303500adf6e88706a1
e811",RUN+="/bin/sh -c 'mknod /dev/asm-emcpoweru b $major $minor; chown grid:asmadmin /dev/asm-emcpoweru; chm
od 0660 /dev/asm-emcpoweru'"

7>然后vi /etc/udev/rules.d/99-oracle-asmdevices.rules新增两条信息，将改好的文件，scp到节点二。

ACTION=="add|change", KERNEL=="emcpower", ENV{DEVTYPE}=="disk",SUBSYSTEM=="block", PROGRAM=="/usr/lib/udev/s
csi_id -g -u -d --whitelisted --replace-whitespace --device=$devnode", RESULT=="360060160f7303500acf6e88706a1
e811",RUN+="/bin/sh -c 'mknod /dev/asm-data15 b $major $minor; chown grid:asmadmin /dev/asm-data15; chmod 066
0 /dev/asm-data15'"
ACTION=="add|change", KERNEL=="emcpower", ENV{DEVTYPE}=="disk",SUBSYSTEM=="block", PROGRAM=="/usr/lib/udev/s
csi_id -g -u -d --whitelisted --replace-whitespace --device=$devnode", RESULT=="360060160f7303500adf6e88706a1
e811",RUN+="/bin/sh -c 'mknod /dev/asm-data16 b $major $minor; chown grid:asmadmin /dev/asm-data16; chmod 066
0 /dev/asm-data16'"

2、udev 确认99.rules文件在两边后，两个节点执行以下命令；
/sbin/udevadm control --reload
/sbin/udevadm trigger --type=devices --action=change
检查磁盘是否属组正确

3、ASM磁盘组加磁盘或创建新的磁盘组。
[grid@dwdb1 ~]$ sqlplus / as sysasm
sysasm$alter diskgroup DATA add disk '/dev/asm-data15','/dev/asm-data16' rebalance power 10; ###该参数可以动态调整，10太慢的话，可以改到中间值5.

--查看执行效率
select group_number,operation,state ,power,est_minutes from v$asm_operation;

--等到执行完成后，改回1，11值为最小性能，1为最大性能
alter diskgroup DATA rebalance power 1;

--至此扩容工作已经完成，下面是具体监控办法
--检查header_status状态，不应该有MEMBER以外的状态
select group_number,disk_number,name,state,path,header_status from v$asm_disk;

--监控alert日志输出结果
2018-08-17T16:43:33.399676+08:00
NOTE: Assigning number (3,14) to disk (/dev/asm-data15)
SUCCESS: completed reconfiguration of group 3 (DATA)
NOTE: Assigning number (3,15) to disk (/dev/asm-data16)
SUCCESS: completed reconfiguration of group 3 (DATA)

--监控查看rebalance进度，完成后查询为空，改回power 为1
select inst_id, operation, state, power, sofar, est_work, est_rate, est_minutes from gv$asm_operation;