问题描述：使用udev绑定磁盘后，rac2节点找不到asm盘。
[root@rac1 ~]# ls -l /dev/asm*
lrwxrwxrwx 1 root root 3 Apr 12 21:34 /dev/asm-data -> sdf
lrwxrwxrwx 1 root root 3 Apr 12 21:34 /dev/asm-fra -> sde
lrwxrwxrwx 1 root root 3 Apr 12 21:34 /dev/asm-ocr1 -> sdb
lrwxrwxrwx 1 root root 3 Apr 12 21:34 /dev/asm-ocr2 -> sdc
lrwxrwxrwx 1 root root 3 Apr 12 21:34 /dev/asm-ocr3 -> sdd
[root@rac2 ~]# ls -l /dev/asm*
ls: cannot access /dev/asm*: No such file or directory
问题分析：

1. 产生设备的UUID
   [root@rac1 soft]# for disk in ls /dev/sd*

do
echo $disk /usr/lib/udev/scsi_id --whitelisted --replace-whitespace --device=$disk
done
/dev/sda
36000c29a3f1f673ab2003650906d8058
/dev/sda1
36000c29a3f1f673ab2003650906d8058
/dev/sda2
36000c29a3f1f673ab2003650906d8058
/dev/sdb
36000c29f23eb1c1c70cb55be9d3bbe83
/dev/sdc
36000c29f1c9adff981a0460809176e82
/dev/sdd
36000c29e10c0ba87351e9abb4d974522
/dev/sde
36000c29795ca76b79287fcdef61dbfb6
/dev/sdf
36000c29d815879e550a21a210d5ed69b
等价于[root@rac1 rules.d]# /usr/lib/udev/scsi_id -g -u -d /dev/sdb
36000c29f23eb1c1c70cb55be9d3bbe83

2. 创建映射文件
   [root@rac1 rules.d]# vi /etc/udev/rules.d/99-oracle-asmdevices.rules

KERNEL==“sd*”, SUBSYSTEM==“block”, PROGRAM=="/usr/lib/udev/scsi_id --whitelisted --replace-whitespace --device=/dev/$name", RESULT=="36000c29f23eb1c1c70cb55be9d3bbe83", SYMLINK+="asm-ocr1", OWNER="grid", GROUP="asmadmin", MODE="0660" KERNEL=="sd*", SUBSYSTEM=="block", PROGRAM=="/usr/lib/udev/scsi_id --whitelisted --replace-whitespace --device=/dev/$name", RESULT==“36000c29f1c9adff981a0460809176e82”, SYMLINK+=“asm-ocr2”, OWNER=“grid”, GROUP=“asmadmin”, MODE=“0660”
KERNEL==“sd*”, SUBSYSTEM==“block”, PROGRAM=="/usr/lib/udev/scsi_id --whitelisted --replace-whitespace --device=/dev/$name", RESULT=="36000c29e10c0ba87351e9abb4d974522", SYMLINK+="asm-ocr3", OWNER="grid", GROUP="asmadmin", MODE="0660" KERNEL=="sd*", SUBSYSTEM=="block", PROGRAM=="/usr/lib/udev/scsi_id --whitelisted --replace-whitespace --device=/dev/$name", RESULT==“36000c29795ca76b79287fcdef61dbfb6”, SYMLINK+=“asm-fra”, OWNER=“grid”, GROUP=“asmadmin”, MODE=“0660”
KERNEL==“sd*”, SUBSYSTEM==“block”, PROGRAM=="/usr/lib/udev/scsi_id --whitelisted --replace-whitespace --device=/dev/$name", RESULT==“36000c29d815879e550a21a210d5ed69b”, SYMLINK+=“asm-data”, OWNER=“grid”, GROUP=“asmadmin”, MODE=“0660”
3) 重新加载分区表（逐个加载）
/sbin/partprobe /dev/sdb
/sbin/partprobe /dev/sdc
/sbin/partprobe /dev/sdd
/sbin/partprobe /dev/sde
/sbin/partprobe /dev/sdf
4) 启动udev
/usr/sbin/udevadm control --reload-rules
systemctl status systemd-udevd.service
systemctl enable systemd-udevd.service
5) 让配置生效：
/sbin/udevadm trigger --type=devices --action=change
udevadm control --reload-rules
6) 检查设备是否正确绑定
[root@rac1 udev]# ls -l /dev/asm*
lrwxrwxrwx 1 root root 3 Apr 12 21:05 /dev/asm-data -> sdf
lrwxrwxrwx 1 root root 3 Apr 12 21:05 /dev/asm-fra -> sde
lrwxrwxrwx 1 root root 3 Apr 12 21:05 /dev/asm-ocr1 -> sdb
lrwxrwxrwx 1 root root 3 Apr 12 21:05 /dev/asm-ocr2 -> sdc
lrwxrwxrwx 1 root root 3 Apr 12 21:05 /dev/asm-ocr3 -> sdd
已尝试的处理方法：
读取第二个节点的磁盘的分区信息依然未能查到绑定磁盘
[root@db12c_02 ~]# fdisk /dev/sdb
Welcome to fdisk (util-linux 2.23.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Command (m for help): p
Disk /dev/sdf: 4294 MB, 4294967296 bytes, 8388608 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0xc1b37f09
[root@rac2 ~]# ls -l /dev/asm*
ls: cannot access /dev/asm*: No such file or directory