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这篇文章给大家分享的是有关如何解决使用 udev 管理 asmdisk 执行 /sbin/scsi_id 不显示 UUID 的问题的内容。丸趣 TV 小编觉得挺实用的，因此分享给大家做个参考，一起跟随丸趣 TV 小编过来看看吧。
在搭建 RAC 的时候，使用 udev 方式来创建 ASM 磁盘，执行 /sbin/scsi_id 命令不知道啥原因, 死活获取不到 UUID, 执行结果啥也不显示。
[root@seiang2 ~]# scsi_id -u -g
/dev/sdb
没有 uuid 貌似没法配置 udev
rules 文件，通过查阅相关资料，通过如下两种方式实现的, 通过 udevinfo（6 版本操作系统 udevadm 取代了 udevinfo）命令获取分区的信息, 可以利用分区中的这 2 项信息 SYSFS{start}== 63 和 SYSFS{size}== 16771797（6 版本变为 ATTR{start}== 4241160 和 ATTR{size}== 2120580）来代替 uuid 唯一标识这个设备；
实验环境：
操作系统：Redhat5.5
Hostname：seiang2.comsys.com
操作系统：Redhat6.4
Hostname：test.comsys.com
目录
一、使用 udevinfo/udevadm 获取分区的唯一标识
二、使用裸设备创建 asm 磁盘
关于 Linux 下的 udev 详细介绍：http://blog.itpub.net/31015730/viewspace-2142429/
一、使用 udevinfo/udevadm 获取分区的唯一标识
新增加一块磁盘，并对它进行分区，分区之后通过 udevinfo/udevadm 命令来获取分区的唯一标识；
Redhat5 版本
[root@seiang2
~]# ll /sbin/udev*
-rwxr-xr-x
1 root root 15176 May 5 2009
/sbin/udevcontrol
-rwxr-xr-x
1 root root 61864 May 5 2009
/sbin/udevd
-rwxr-xr-x
1 root root 899928 May 5 2009 /sbin/udevd.static
-rwxr-xr-x
1 root root 23680 May 5 2009
/sbin/udevsettle
-rwxr-xr-x
1 root root 24144 May 5 2009
/sbin/udevtrigger
[root@seiang2
~]# cd
/sys/block/sdb
[root@seiang2
~]# udevinfo -a
-p /sys/block/sdb
Udevinfo
starts with the device specified by the devpath and then
walks
up the chain of parent devices. It prints for every device
found,
all possible attributes in the udev rules key format.
rule to match, can be composed by the attributes of the device
the attributes from one single parent device.
looking at device /block/sdb :
KERNEL== sdb
SUBSYSTEM== block
SYSFS{stat}== 63
93 1248 19
0 0 0
0 0 19
19
SYSFS{size}== 10485760
SYSFS{removable}== 0
SYSFS{range}== 16
SYSFS{dev}== 8:16
looking at parent device
/devices/pci0000:00/0000:00:0d.0/host1/target1:0:0/1:0:0:0 :
ID== 1:0:0:0
BUS== scsi
DRIVER== sd
SYSFS{dh_state}== detached
SYSFS{ioerr_cnt}== 0x0
SYSFS{iodone_cnt}== 0x51
SYSFS{iorequest_cnt}== 0x51
SYSFS{iocounterbits}== 32
SYSFS{timeout}== 60
SYSFS{state}== running
SYSFS{rev}== 1.0
SYSFS{model}== VBOX HARDDISK
SYSFS{vendor}== ATA
SYSFS{scsi_level}== 6
SYSFS{type}== 0
SYSFS{queue_type}== simple
SYSFS{queue_depth}== 31
SYSFS{device_blocked}== 0
looking at parent device
/devices/pci0000:00/0000:00:0d.0/host1/target1:0:0 :
ID== target1:0:0
BUS==
DRIVER==
looking at parent device
/devices/pci0000:00/0000:00:0d.0/host1 :
ID== host1
BUS==
DRIVER==
looking at parent device
/devices/pci0000:00/0000:00:0d.0 :
ID== 0000:00:0d.0
BUS== pci
DRIVER== ahci
SYSFS{broken_parity_status}== 0
SYSFS{enable}== 1
SYSFS{modalias}== pci:v00008086d00002829sv00000000sd00000000bc01sc06i01
SYSFS{local_cpus}== 00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000
SYSFS{irq}== 177
SYSFS{class}== 0x010601
SYSFS{subsystem_device}== 0x0000
SYSFS{subsystem_vendor}== 0x0000
SYSFS{device}== 0x2829
SYSFS{vendor}== 0x8086
looking at parent device /devices/pci0000:00 :
ID== pci0000:00
BUS==
DRIVER==
[root@seiang2
~]# fdisk
/dev/sdb
Device
contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building
a new DOS disklabel. Changes will remain in memory only,
until
you decide to write them. After that, of course, the previous
content
won t be recoverable.
Warning:
invalid flag 0x0000 of partition table 4 will be corrected by w(rite)
Command
(m for help): n
Command
action
e
extended
p
primary partition (1-4)
p
Partition
number (1-4): 1
First
cylinder (1-652, default 1):
Using
default value 1
Last
cylinder or +size or +sizeM or +sizeK (1-652, default 652): +1G
Command
(m for help): n
Command
action
e
extended
p
primary partition (1-4)
p
Partition
number (1-4): 2
First
cylinder (124-652, default 124):
Using
default value 124
Last
cylinder or +size or +sizeM or +sizeK (124-652, default 652): +1G
Command
(m for help): n
Command
action
e
extended
p
primary partition (1-4)
p
Partition
number (1-4): 3
First
cylinder (126-652, default 126):
Using
default value 126
Last
cylinder or +size or +sizeM or +sizeK (126-652, default 652): +1G
Command
(m for help): p
Disk
/dev/sdb: 5368 MB, 5368709120 bytes
heads, 63 sectors/track, 652 cylinders
Units
= cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks
Id System
/dev/sdb1 1 123 987966
83 Linux
/dev/sdb2 124 125 16065
83 Linux
/dev/sdb3 126 248 987997+
83 Linux
Command
(m for help): w
partition table has been altered!
Calling
ioctl() to re-read partition table.
Syncing
disks.
[root@seiang2
~]# ll /dev/sdb*
brw-r—–
1 root disk 8, 16 Jul 20 02:57 /dev/sdb
brw-r—–
1 root disk 8, 17 Jul 20 02:57 /dev/sdb1
brw-r—–
1 root disk 8, 18 Jul 20 02:57 /dev/sdb2
brw-r—–
1 root disk 8, 19 Jul 20 02:57 /dev/sdb3
使用 udevinfo 命令查看详细的分区信息
[root@seiang2
~]# udevinfo -a
-p /sys/block/sdb/sdb1
Udevinfo
starts with the device specified by the devpath and then
walks
up the chain of parent devices. It prints for every device
found,
all possible attributes in the udev rules key format.
rule to match, can be composed by the attributes of the device
the attributes from one single parent device.
looking at device /block/sdb/sdb1 :
KERNEL== sdb1
SUBSYSTEM== block
SYSFS{stat}== 31
67 392 19
0 0 0
0 0 17
19
SYSFS{size}== 1975932
SYSFS{start}== 63
SYSFS{dev}== 8:17
looking at parent device /block/sdb :
ID== sdb
BUS== block
DRIVER==
SYSFS{stat}== 196
575 3152 94
1 0 8
2 0 71
96
SYSFS{size}== 10485760
SYSFS{removable}== 0
SYSFS{range}== 16
SYSFS{dev}== 8:16
looking at parent device
/devices/pci0000:00/0000:00:0d.0/host1/target1:0:0/1:0:0:0 :
ID== 1:0:0:0
BUS== scsi
DRIVER== sd
SYSFS{dh_state}== detached
SYSFS{ioerr_cnt}== 0x0
SYSFS{iodone_cnt}== 0xe1
SYSFS{iorequest_cnt}== 0xe1
SYSFS{iocounterbits}== 32
SYSFS{timeout}== 60
SYSFS{state}== running
SYSFS{rev}== 1.0
SYSFS{model}== VBOX HARDDISK
SYSFS{vendor}== ATA
SYSFS{scsi_level}== 6
SYSFS{type}== 0
SYSFS{queue_type}== simple
SYSFS{queue_depth}== 31
SYSFS{device_blocked}== 0
looking at parent device
/devices/pci0000:00/0000:00:0d.0/host1/target1:0:0 :
ID== target1:0:0
BUS==
DRIVER==
looking at parent device
/devices/pci0000:00/0000:00:0d.0/host1 :
ID== host1
BUS==
DRIVER==
looking at parent device
/devices/pci0000:00/0000:00:0d.0 :
ID== 0000:00:0d.0
BUS== pci
DRIVER== ahci
SYSFS{broken_parity_status}== 0
SYSFS{enable}== 1
SYSFS{modalias}== pci:v00008086d00002829sv00000000sd00000000bc01sc06i01
SYSFS{local_cpus}== 00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000
SYSFS{irq}== 177
SYSFS{class}== 0x010601
SYSFS{subsystem_device}== 0x0000
SYSFS{subsystem_vendor}== 0x0000
SYSFS{device}== 0x2829
SYSFS{vendor}== 0x8086
looking at parent device
/devices/pci0000:00 :
ID== pci0000:00
BUS==
DRIVER==
[root@seiang2
rules.d]# udevinfo -a -p /sys/block/sdb/sdb3/
Udevinfo
starts with the device specified by the devpath and then
walks
up the chain of parent devices. It prints for every device
found,
all possible attributes in the udev rules key format.
rule to match, can be composed by the attributes of the device
the attributes from one single parent device.
looking
at device /block/sdb/sdb3 :
KERNEL== sdb3
SUBSYSTEM== block
SYSFS{stat}== 27
355 382 31
0 0 0
0 0 31
31
SYSFS{size}== 1975995
SYSFS{start}== 2008125
SYSFS{dev}== 8:19
looking at parent device /block/sdb :
ID== sdb
BUS== block
DRIVER==
SYSFS{stat}== 395
1754 5700 383
2 0 16
8 0 242
391
SYSFS{size}== 10485760
SYSFS{removable}== 0
SYSFS{range}== 16
SYSFS{dev}== 8:16
looking at parent device
/devices/pci0000:00/0000:00:0d.0/host1/target1:0:0/1:0:0:0 :
ID== 1:0:0:0
BUS== scsi
DRIVER== sd
SYSFS{dh_state}== detached
SYSFS{ioerr_cnt}== 0x0
SYSFS{iodone_cnt}== 0x1b3
SYSFS{iorequest_cnt}== 0x1b3
SYSFS{iocounterbits}== 32
SYSFS{timeout}== 60
SYSFS{state}== running
SYSFS{rev}== 1.0
SYSFS{model}== VBOX HARDDISK
SYSFS{vendor}== ATA
SYSFS{scsi_level}== 6
SYSFS{type}== 0
SYSFS{queue_type}== simple
SYSFS{queue_depth}== 31
SYSFS{device_blocked}== 0
looking at parent device
/devices/pci0000:00/0000:00:0d.0/host1/target1:0:0 :
ID== target1:0:0
BUS==
DRIVER==
looking at parent device
/devices/pci0000:00/0000:00:0d.0/host1 :
ID== host1
BUS==
DRIVER==
looking at parent device
/devices/pci0000:00/0000:00:0d.0 :
ID== 0000:00:0d.0
BUS== pci
DRIVER== ahci
SYSFS{broken_parity_status}== 0
SYSFS{enable}== 1
SYSFS{modalias}== pci:v00008086d00002829sv00000000sd00000000bc01sc06i01
SYSFS{local_cpus}== 00000000,00000000,00000000,00000000,00000000,00000000,00000000,00000000
SYSFS{irq}== 177
SYSFS{class}== 0x010601
SYSFS{subsystem_device}== 0x0000
SYSFS{subsystem_vendor}== 0x0000
SYSFS{device}== 0x2829
SYSFS{vendor}== 0x8086
looking at parent device
/devices/pci0000:00 :
ID== pci0000:00
BUS==
DRIVER==
编辑 udev 的 rule 文件
[root@seiang2
~]# cd
/etc/udev/rules.d/
[root@seiang2
rules.d]# vim
99-oracle-asmdevices.rules
KERNEL== sdb1 ,
SUBSYSTEM== block , SYSFS{size}== 1975932 , SYSFS{start}== 63 ,
OWNER= grid ,NAME= asmdisk-data1 ,
GROUP= asmadmin , MODE= 0660
KERNEL== sdb3 ,
SUBSYSTEM== block , SYSFS{size}== 1975995 , SYSFS{start}== 2008125 ,
OWNER= grid ,NAME= asmdisk-data2 ,
GROUP= asmadmin , MODE= 0660
编辑 rule 文件之后可以使用 udevtest 测试 udev 对设备的管理, 命名, 链接以及权限的设置情况
[root@seiang2
rules.d]# udevtest
/block/sdb
main:
looking at device /block/sdb from subsystem block
run_program:
/lib/udev/usb_id -x
run_program:
/lib/udev/usb_id returned with status 1
run_program:
/lib/udev/scsi_id -g -x -s /block/sdb -d /dev/.tmp-8-16
run_program:
/lib/udev/scsi_id (stdout) ID_VENDOR=ATA
run_program:
/lib/udev/scsi_id (stdout) ID_MODEL=VBOX_HARDDISK
run_program:
/lib/udev/scsi_id (stdout) ID_REVISION=1.0
run_program:
/lib/udev/scsi_id (stdout) ID_SERIAL=SATA_VBOX_HARDDISK_VBda65d90d-e2055c6a
run_program:
/lib/udev/scsi_id (stdout) ID_TYPE=disk
run_program:
/lib/udev/scsi_id (stdout) ID_BUS=scsi
run_program:
/lib/udev/scsi_id returned with status 0
udev_rules_get_name:
add symlink disk/by-id/scsi-SATA_VBOX_HARDDISK_VBda65d90d-e2055c6a
run_program:
/lib/udev/path_id /block/sdb
run_program:
/lib/udev/path_id (stdout) ID_PATH=pci-0000:00:0d.0-scsi-1:0:0:0
run_program:
/lib/udev/path_id returned with status 0
udev_rules_get_name:
add symlink disk/by-path/pci-0000:00:0d.0-scsi-1:0:0:0
run_program:
/lib/udev/vol_id –export /dev/.tmp-8-16
run_program:
/lib/udev/vol_id returned with status 4
run_program:
/lib/udev/edd_id –export /dev/.tmp-8-16
run_program:
/lib/udev/edd_id (stderr) no kernel EDD support
run_program:
/lib/udev/edd_id returned with status 2
udev_rules_get_name:
no node name set, will use kernel name sdb
udev_device_event:
device /block/sdb already in database, validate currently present symlinks
udev_node_add:
creating device node /dev/sdb , major = 8 , minor = 16 , mode = 0640 , uid
= 0 , gid = 6
udev_node_add:
creating symlink /dev/disk/by-id/scsi-SATA_VBOX_HARDDISK_VBda65d90d-e2055c6a
to ../../sdb
udev_node_add:
creating symlink /dev/disk/by-path/pci-0000:00:0d.0-scsi-1:0:0:0 to
../../sdb
main:
run: socket:/org/kernel/udev/monitor
main:
run: /lib/udev/udev_run_devd
main:
run: socket:/org/freedesktop/hal/udev_event
main:
run: /sbin/pam_console_apply /dev/sdb /dev/disk/by-id/scsi-SATA_VBOX_HARDDISK_VBda65d90d-e2055c6a
/dev/disk/by-path/pci-0000:00:0d.0-scsi-1:0:0:0
重新启动 udev, 在启动之前首先使用命令 udevcontrol 重新装载 rules（此步骤可以省略）
[root@seiang2
rules.d]# udevcontrol
reload_rules
[root@seiang2
rules.d]# start_udev
Starting
udev:
[ OK ]
[root@seiang2
rules.d]# ll
/dev/asm*
brw-rw—-
1 grid asmadmin 8, 17 Jul 20 03:09 /dev/asmdisk-data1
brw-rw—-
1 grid asmadmin 8, 19 Jul 20 03:09 /dev/asmdisk-data2
[root@seiang2
rules.d]#
Redhat6 版本
[root@test
rules.d]# udevadm
info -a -p /sys/block/sdb/sdb2
Udevadm
info starts with the device specified by the devpath and then
walks
up the chain of parent devices. It prints for every device
found,
all possible attributes in the udev rules key format.
rule to match, can be composed by the attributes of the device
the attributes from one single parent device.
looking at device
/devices/pci0000:00/0000:00:0d.0/host3/target3:0:0/3:0:0:0/block/sdb/sdb2 :
KERNEL== sdb2
SUBSYSTEM== block
DRIVER==
ATTR{partition}== 2
ATTR{start}== 2120580
ATTR{size}== 2120580
ATTR{alignment_offset}== 0
ATTR{discard_alignment}== 0
ATTR{stat}== 238
84 1288 247
0 0 0
0 0 232
247
ATTR{inflight}== 0
0
looking at parent device
/devices/pci0000:00/0000:00:0d.0/host3/target3:0:0/3:0:0:0/block/sdb :
KERNELS== sdb
SUBSYSTEMS== block
DRIVERS==
ATTRS{range}== 16
ATTRS{ext_range}== 256
ATTRS{removable}== 0
ATTRS{ro}== 0
ATTRS{size}== 10485760
ATTRS{alignment_offset}== 0
ATTRS{discard_alignment}== 0
ATTRS{capability}== 52
ATTRS{stat}== 2082
4734 15818 2580
640 98980 99628
48250 0 2549
50830
ATTRS{inflight}== 0
0
looking at parent device
/devices/pci0000:00/0000:00:0d.0/host3/target3:0:0/3:0:0:0 :
KERNELS== 3:0:0:0
SUBSYSTEMS== scsi
DRIVERS== sd
ATTRS{device_blocked}== 0
ATTRS{type}== 0
ATTRS{scsi_level}== 6
ATTRS{vendor}== ATA
ATTRS{model}== VBOX HARDDISK
ATTRS{rev}== 1.0
ATTRS{state}== running
ATTRS{timeout}== 30
ATTRS{iocounterbits}== 32
ATTRS{iorequest_cnt}== 0xb10
ATTRS{iodone_cnt}== 0xb0e
ATTRS{ioerr_cnt}== 0xf
ATTRS{modalias}== scsi:t-0x00
ATTRS{evt_media_change}== 0
ATTRS{dh_state}== detached
ATTRS{queue_depth}== 31
ATTRS{queue_ramp_up_period}== 120000
ATTRS{queue_type}== simple
looking at parent device
/devices/pci0000:00/0000:00:0d.0/host3/target3:0:0 :
KERNELS== target3:0:0
SUBSYSTEMS== scsi
DRIVERS==
looking at parent device
/devices/pci0000:00/0000:00:0d.0/host3 :
KERNELS== host3
SUBSYSTEMS== scsi
DRIVERS==
looking at parent device
/devices/pci0000:00/0000:00:0d.0 :
KERNELS== 0000:00:0d.0
SUBSYSTEMS== pci
DRIVERS== ahci
ATTRS{vendor}== 0x8086
ATTRS{device}== 0x2829
ATTRS{subsystem_vendor}== 0x0000
ATTRS{subsystem_device}== 0x0000
ATTRS{class}== 0x010601
ATTRS{irq}== 21
ATTRS{local_cpus}== 1
ATTRS{local_cpulist}== 0
ATTRS{modalias}== pci:v00008086d00002829sv00000000sd00000000bc01sc06i01
ATTRS{numa_node}== -1
ATTRS{enable}== 1
ATTRS{broken_parity_status}== 0
ATTRS{msi_bus}==
looking at parent device
/devices/pci0000:00 :
KERNELS== pci0000:00
SUBSYSTEMS==
DRIVERS==
[root@test
rules.d]# udevadm
info -a -p /sys/block/sdb/sdb3
Udevadm
info starts with the device specified by the devpath and then
walks
up the chain of parent devices. It prints for every device
found,
all possible attributes in the udev rules key format.
rule to match, can be composed by the attributes of the device
the attributes from one single parent device.
looking at device
/devices/pci0000:00/0000:00:0d.0/host3/target3:0:0/3:0:0:0/block/sdb/sdb3 :
KERNEL== sdb3
SUBSYSTEM== block
DRIVER==
ATTR{partition}== 3
ATTR{start}== 4241160
ATTR{size}== 2120580
ATTR{alignment_offset}== 0
ATTR{discard_alignment}== 0
ATTR{stat}== 200
122 1288 255
0 0 0
0 0 250
255
ATTR{inflight}== 0
0
looking at parent device
/devices/pci0000:00/0000:00:0d.0/host3/target3:0:0/3:0:0:0/block/sdb :
KERNELS== sdb
SUBSYSTEMS== block
DRIVERS==
ATTRS{range}== 16
ATTRS{ext_range}== 256
ATTRS{removable}== 0
ATTRS{ro}== 0
ATTRS{size}== 10485760
ATTRS{alignment_offset}== 0
ATTRS{discard_alignment}== 0
ATTRS{capability}== 52
ATTRS{stat}== 2082
4734 15818 2580
640 98980 99628
48250 0 2549
50830
ATTRS{inflight}== 0
0
looking at parent device
/devices/pci0000:00/0000:00:0d.0/host3/target3:0:0/3:0:0:0 :
KERNELS== 3:0:0:0
SUBSYSTEMS== scsi
DRIVERS== sd
ATTRS{device_blocked}== 0
ATTRS{type}== 0
ATTRS{scsi_level}== 6
ATTRS{vendor}== ATA
ATTRS{model}== VBOX HARDDISK
ATTRS{rev}== 1.0
ATTRS{state}== running
ATTRS{timeout}== 30
ATTRS{iocounterbits}== 32
ATTRS{iorequest_cnt}== 0xb10
ATTRS{iodone_cnt}== 0xb0e
ATTRS{ioerr_cnt}== 0xf
ATTRS{modalias}== scsi:t-0x00
ATTRS{evt_media_change}== 0
ATTRS{dh_state}== detached
ATTRS{queue_depth}== 31
ATTRS{queue_ramp_up_period}== 120000
ATTRS{queue_type}== simple
looking at parent device
/devices/pci0000:00/0000:00:0d.0/host3/target3:0:0 :
KERNELS== target3:0:0
SUBSYSTEMS== scsi
DRIVERS==
looking at parent device
/devices/pci0000:00/0000:00:0d.0/host3 :
KERNELS== host3
SUBSYSTEMS== scsi
DRIVERS==
looking at parent device
/devices/pci0000:00/0000:00:0d.0 :
KERNELS== 0000:00:0d.0
SUBSYSTEMS== pci
DRIVERS== ahci
ATTRS{vendor}== 0x8086
ATTRS{device}== 0x2829
ATTRS{subsystem_vendor}== 0x0000
ATTRS{subsystem_device}== 0x0000
ATTRS{class}== 0x010601
ATTRS{irq}== 21
ATTRS{local_cpus}== 1
ATTRS{local_cpulist}== 0
ATTRS{modalias}== pci:v00008086d00002829sv00000000sd00000000bc01sc06i01
ATTRS{numa_node}== -1
ATTRS{enable}== 1
ATTRS{broken_parity_status}== 0
ATTRS{msi_bus}==
looking at parent device
/devices/pci0000:00 :
KERNELS== pci0000:00
SUBSYSTEMS==
DRIVERS==
[root@test
rules.d]# vim
99-oracle-asmdevices.rules
KERNEL== sdb2 ,
SUBSYSTEM== block , ATTR{size}== 2120580 , ATTR{start}== 2120580 ,
OWNER= grid ,NAME= asmdisk-data1 ,
GROUP= asmadmin , MODE= 0660
KERNEL== sdb3 ,
SUBSYSTEM== block , ATTR{size}== 2120580 , ATTR{start}== 4241160 ,
OWNER= grid ,NAME= asmdisk-data2 ,
GROUP= asmadmin , MODE= 0660
[root@test
rules.d]# start_udev
Starting
udev:
[ OK ]
[root@test
rules.d]# ll
/dev/asm*
brw-rw—-.
1 grid asmadmin 8, 18 Jul 20 15:57 /dev/asmdisk-data1
brw-rw—-.
1 grid asmadmin 8, 19 Jul 20 15:57 /dev/asmdisk-data2
注意：从这里可以看到通过配置 99-oracle-asmdevices.rules 文件，创建出来的是块类型的设备
可以对比观察下面通过裸设备创建出来的设备类型
二、使用裸设备创建 asm 磁盘
新增加一块磁盘，并对其进行分区；
[root@seiang2
rules.d]# fdisk /dev/sdb
Command
(m for help): n
Command
action
e
extended
p
primary partition (1-4)
e
Selected
partition 4
First
cylinder (249-652, default 249):
Using
default value 249
Last
cylinder or +size or +sizeM or +sizeK (249-652, default 652):
Using
default value 652
Command
(m for help): n
First
cylinder (249-652, default 249):
Using
default value 249
Last
cylinder or +size or +sizeM or +sizeK (249-652, default 652): +1G
Command
(m for help): n
First
cylinder (372-652, default 372):
Using
default value 372
Last
cylinder or +size or +sizeM or +sizeK (372-652, default 652): +1G
Command
(m for help): w
partition table has been altered!
Calling
ioctl() to re-read partition table.
Syncing
disks.
[root@seiang2
rules.d]# fdisk
-l
Disk
/dev/sda: 16.1 GB, 16106127360 bytes
heads, 63 sectors/track, 1958 cylinders
Units
= cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks
Id System
/dev/sda1 *
1 13 104391
83 Linux
/dev/sda2 14 1958
15623212+ 8e Linux LVM
Disk
/dev/sdb: 5368 MB, 5368709120 bytes
heads, 63 sectors/track, 652 cylinders
Units
= cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks
Id System
/dev/sdb1 1 123 987966
83 Linux
/dev/sdb2 124 125 16065
83 Linux
/dev/sdb3 126 248 987997+
83 Linux
/dev/sdb4 249 652
3245130 5 Extended
/dev/sdb5 249 371 987966
83 Linux
/dev/sdb6 372 494 987966
83 Linux
配置裸设备映射，修改 /etc/udev/rules.d/60-raw.rules 文件
[root@seiang2
rules.d]# vim
60-raw.rules
ACTION== add ,
KERNEL== /dev/sdb5 , RUN+= /bin/raw /dev/raw/raw5 %N
ACTION== add ,
ENV{MAJOR}== 8 , ENV{MINOR}== 1 , RUN+= /bin/raw
/dev/raw/raw5 %M %m
ACTION== add ,
KERNEL== /dev/sdb6 , RUN+= /bin/raw /dev/raw/raw6 %N
ACTION== add ,
ENV{MAJOR}== 8 , ENV{MINOR}== 2 , RUN+= /bin/raw
/dev/raw/raw6 %M %m
ACTION== add ,
KERNEL== raw5 , OWNER= grid , GROUP= asmadmin ,
MODE= 0660
ACTION== add ,
KERNEL== raw6 , OWNER= grid , GROUP= asmadmin ,
MODE= 0660
重启 udev 服务，并查询 raw
[root@seiang2
rules.d]# start_udev
Starting
udev:
[ OK ]
[root@seiang2
rules.d]# raw
-qa
/dev/raw/raw5: bound to major 8, minor 1
/dev/raw/raw6: bound to major 8, minor 2
[root@seiang2
rules.d]# ll
/dev/raw*
crw——-
1 root root 162, 0 Jul 20 02:53 /dev/rawctl
/dev/raw:
total
0
crw-rw—- 1 grid
asmadmin 162, 5 Jul 20 03:31 raw5
crw-rw—- 1 grid
asmadmin 162, 6 Jul 20 03:31 raw6
注意：从这里可以看到通过配置 60-raw.rules 文件，创建出来的是字符类型的设备
这样配置之后，裸设备文件会自动映射到相应的分区设备文件，并设置正确的用户和组。
裸设备介绍 (来自 http://blog.itpub.net/26736162/viewspace-1401193/)
裸设备：也叫裸分区（原始分区），是一种没有经过格式化，不被 Unix/Linux 通过文件系统来读取的特殊字符设备。裸设备可以绑定一个分区，也可以绑定一个磁盘。
字符设备：对字符设备的读写不需要通过 OS 的 buffer。它不可被文件系统 mount。
块设备：对块设备的读写需要通过 OS 的 buffer，它可以被 mount 到文件系统中。
这个与 linux 的版本相关，在旧版本中，最多只可以有 256 个裸设备，Linux 4 下做多可以绑定 81Array2 个裸设备。但是在 linux 下，最多只能有 255 个分区，所以，如果用裸设备绑定分区，最多只能绑定 255 个裸设备。如果是用 lvm，则没有这个限制。
Linux 下单个磁盘最多可以有 15 个分区。3 个主分区 + 1 个扩展分区 + 11 个逻辑分区。
建议的分区方法是：先分 3 个主分区，第四个分区为扩展分区，然后在扩展分区中再分成 11 个逻辑分区。
注意: 裸设备不要绑定在扩展分区上。 linux 下如果需要使用裸设备，则需要手工进行绑定，unix 下则不用。
major 和 minor device
number
在 unix/linux 系统中，一切都是文件。所有硬盘、键盘等设备都用文件来代表，对应着 /dev 下面的文件。对于应用程序来说，可以像对待普通文件一样打开，关闭、读写这些设备文件。但是这种文件名，比如 /dev/sda、/dev /raw/raw1 都是用户空间名称，OS Kernel 根本不知道这个名称指的是什么。在内核空间是通过 major、minor device
number 来区分设备的。
major device number 可以看作是设备驱动程序，被同一设备驱动程序管理的设备有相同的 major device
number。这个数字实际是 Kernel 中 device driver
table 的索引，这个表保存着不同设备驱动程序。而 minor device
number 用来代表被访问的具体设备。也就是说 Kernel 根据 major device
number 找到设备驱动程序，然后再从 minor device
number 获得设备位置等属性。所有这些 major device
number 是已经预先分配好的。比如裸设备是 162，scsi 块设备是 8
Redhat 平台对 raw 设备的配置在 redhat 5 之后有了变化。在 redhat 5 之前，直接配置 /etc/sysconfig/rawdevices 件，通过 /etc/init.d/rawdevices 来管理 raw 设备的启动和关闭。在 Redhat 5 之后，原来的 raw 设备接口已经取消了，redhat 5 中通过 udev 规则进行配置。要配置，需要编辑 /etc/udev/rules.d/60-raw.rules 这个文件。
cat /etc/udev/rules.d/60-raw.rules
# Enter raw device bindings here.
#
# An example would be:
# ACTION== add , KERNEL== sda ,
RUN+= /bin/raw /dev/raw/raw1 %N
# to bind /dev/raw/raw1 to /dev/sda, or
# ACTION== add , ENV{MAJOR}== 8 ,
ENV{MINOR}== 1 , RUN+= /bin/raw /dev/raw/raw2 %M %m
# to bind /dev/raw/raw2 to the device with major 8, minor 1.
其中
ACTION== add , KERNEL= , RUN+= raw /dev/raw/rawX
%N
配置设备名称，用你需要绑定的设备名称替换（如：/dev/sda1），X 为裸设备号
主 / 次号码：
ACTION== add , ENV{MAJOR}= A ,
ENV{MINOR}= B , RUN+= raw /dev/raw/rawX %M %m
A 和 B 是设备的主 / 次号码，X 是系统使用的 raw 设备号码。
个人对 redhat 管理 raw 的过程理解为：在 redhat 5 中，是通过 udev 来管理 raw 设备的，而 udev 是通过 MAJOR 和 MINOR 来识别 raw 设备。故需要将设备号和裸设备号进行绑定，而主设备号和次设备号可以自行指定或者由系统自动分配。根据 red hat 的官方文档中关于 raw.rule 的示例中说 KERNEL==.. 或 ENV{MAJOR}… 只需要任意配置一个就可以，但有些网友经过试验，验证必须二者同时配置才可以。
如果有多个 raw 设备，可以写成：
ACTION== add , KERNEL== raw[1-4] ,
OWNER= dave , GROUP= tianlesoftware , MODE= 0660
注意：在内核 2.6.9-89.5AXS2 之前使用 /etc/sysconfig/rawdevices 和 /etc/udev/permissions.d/50-udev.permissions 进行 raw 设备的配置和权限管理。在内核 2.6.18-128.7AXS3 以后则使用了本文介绍的 /etc/udev/rules.d/60-raw.rules 进行 raw 设备的管理
使用裸设备作为 Oracle 的数据文件的注意事项
1、一个裸设备只能放置一个数据文件
2、数据文件的大小不能超过裸设备的大小
如果是日志文件，则裸设备最大可用大小 = 裸设备对应分区大小 – 1 * 512（保留一个 redo lock）
如果是数据文件，则裸设备最大可用大小 = 裸设备对应分区大小 – 2 *
db_block_size（保留两个 block）
为了简单起见，对所有的文件设置称比裸设备小 1M 即可。
3、数据文件最好不要设置称自动扩展，如果设置称自动扩展，一定要把 maxsize 设置设置为比裸设备小
4、linux 下 oracle 不能直接把逻辑卷作为裸设备，也要进行绑定。unix 下就不需要。
感谢各位的阅读！关于“如何解决使用 udev 管理 asmdisk 执行 /sbin/scsi_id 不显示 UUID 的问题”这篇文章就分享到这里了，希望以上内容可以对大家有一定的帮助，让大家可以学到更多知识，如果觉得文章不错，可以把它分享出去让更多的人看到吧！
