Centos5上部署udev

首先来简要的介绍下什么是udev,udev是Linux kernel 2.6系列的通用内核设备管理器,以守护进程的方式运行于Linux系统，并监听在新设备初始化或设备从系统中移除时，内核（通过netlink socket）所发出的uevent；简单点讲就是当有多块磁盘的时候，可以用udev来固定磁盘对应的设备名；之前在部署11g rac的时候都偏好使用asmlib，在最近一次的部署中asmlib出现了问题，而又没有时间去排错，因而采用udev部署，故而简单记录下udev的配置过程！

一：模拟共享盘阵，这里采用先划分lvm，再通过iscsi共享的方式来模拟

[root@db1 ~]# pvcreate /dev/sdb
  Physical volume "/dev/sdb" successfully created
[root@db1 ~]# vgcreate data /dev/sdb
  /dev/hdc: open failed: Read-only file system
  /dev/cdrom: open failed: Read-only file system
  Attempt to close device '/dev/cdrom' which is not open.
  Volume group "data" successfully created
[root@db1 ~]# lvcreate -n crs1 -L 2G data
  Logical volume "crs1" created
[root@db1 ~]# lvcreate -n crs2 -L 2G data
  Logical volume "crs2" created
[root@db1 ~]# lvcreate -n crs3 -L 2G data
  Logical volume "crs3" created
[root@db1 ~]# lvcreate -n data -L 10G data
  Logical volume "data" created
[root@db1 ~]# lvcreate -n fra -L 10G data
  Logical volume "fra" created

[root@db1 ~]# lvs
  LV   VG   Attr   LSize  Origin Snap%  Move Log Copy%  Convert
  crs1 data -wi-a-  2.00G
  crs2 data -wi-a-  2.00G
  crs3 data -wi-a-  2.00G
  data data -wi-a- 10.00G
  fra  data -wi-a- 10.00G

[root@db1 ~]# service tgtd start
Starting SCSI target daemon: [  OK  ]

[root@db1 ~]# cat iscsi.sh
tgtadm  --lld iscsi --op new --mode target --tid 1 -T iqn.2012-07-04.com.yang.rac:crs1
tgtadm  --lld iscsi --op new --mode target --tid 2 -T iqn.2012-07-04.com.yang.rac:crs2
tgtadm  --lld iscsi --op new --mode target --tid 3 -T iqn.2012-07-04.com.yang.rac:crs3
tgtadm  --lld iscsi --op new --mode target --tid 4 -T iqn.2012-07-04.com.yang.rac:data
tgtadm  --lld iscsi --op new --mode target --tid 5 -T iqn.2012-07-04.com.yang.rac:fra

tgtadm  --lld iscsi --op new --mode logicalunit --tid 1 --lun 1 -b /dev/data/crs1
tgtadm  --lld iscsi --op new --mode logicalunit --tid 1 --lun 2 -b /dev/data/crs2
tgtadm  --lld iscsi --op new --mode logicalunit --tid 1 --lun 3 -b /dev/data/crs3
tgtadm  --lld iscsi --op new --mode logicalunit --tid 1 --lun 4 -b /dev/data/data
tgtadm  --lld iscsi --op new --mode logicalunit --tid 1 --lun 5 -b /dev/data/fra

tgtadm  --lld iscsi --op bind --mode target --tid 1 -I ALL
tgtadm  --lld iscsi --op bind --mode target --tid 2 -I ALL
tgtadm  --lld iscsi --op bind --mode target --tid 3 -I ALL
tgtadm  --lld iscsi --op bind --mode target --tid 4 -I ALL
tgtadm  --lld iscsi --op bind --mode target --tid 5 -I ALL

[root@db1 ~]# tgtadm --lld iscsi -o show -m target
[root@db1 ~]# sh iscsi.sh
[root@db1 ~]# tgtadm --lld iscsi -o show -m target
Target 1: iqn.2012-07-04.com.yang.rac:crs1
    System information:
        Driver: iscsi
        State: ready
    I_T nexus information:
    LUN information:
        LUN: 0
            Type: controller
            SCSI ID: deadbeaf1:0
            SCSI SN: beaf10
            Size: 0 MB
            Online: Yes
            Removable media: No
            Backing store: No backing store
        LUN: 1
            Type: disk
            SCSI ID: deadbeaf1:1
            SCSI SN: beaf11
            Size: 2147 MB
            Online: Yes
            Removable media: No
            Backing store: /dev/data/crs1
        LUN: 2
            Type: disk
            SCSI ID: deadbeaf1:2
            SCSI SN: beaf12
            Size: 2147 MB
            Online: Yes
            Removable media: No
            Backing store: /dev/data/crs2
        LUN: 3
            Type: disk
            SCSI ID: deadbeaf1:3
            SCSI SN: beaf13
            Size: 2147 MB
            Online: Yes
            Removable media: No
            Backing store: /dev/data/crs3
        LUN: 4
            Type: disk
            SCSI ID: deadbeaf1:4
            SCSI SN: beaf14
            Size: 10737 MB
            Online: Yes
            Removable media: No
            Backing store: /dev/data/data
        LUN: 5
            Type: disk
            SCSI ID: deadbeaf1:5
            SCSI SN: beaf15
            Size: 10737 MB
            Online: Yes
            Removable media: No
            Backing store: /dev/data/fra
    Account information:
    ACL information:
        ALL
Target 2: iqn.2012-07-04.com.yang.rac:crs2
    System information:
        Driver: iscsi
        State: ready
    I_T nexus information:
    LUN information:
        LUN: 0
            Type: controller
            SCSI ID: deadbeaf2:0
            SCSI SN: beaf20
            Size: 0 MB
            Online: Yes
            Removable media: No
            Backing store: No backing store
    Account information:
    ACL information:
Target 3: iqn.2012-07-04.com.yang.rac:crs3
    System information:
        Driver: iscsi
        State: ready
    I_T nexus information:
    LUN information:
        LUN: 0
            Type: controller
            SCSI ID: deadbeaf3:0
            SCSI SN: beaf30
            Size: 0 MB
            Online: Yes
            Removable media: No
            Backing store: No backing store
    Account information:
    ACL information:
Target 4: iqn.2012-07-04.com.yang.rac:data
    System information:
        Driver: iscsi
        State: ready
    I_T nexus information:
    LUN information:
        LUN: 0
            Type: controller
            SCSI ID: deadbeaf4:0
            SCSI SN: beaf40
            Size: 0 MB
            Online: Yes
            Removable media: No
            Backing store: No backing store
    Account information:
    ACL information:
Target 5: iqn.2012-07-04.com.yang.rac:fra
    System information:
        Driver: iscsi
        State: ready
    I_T nexus information:
    LUN information:
        LUN: 0
            Type: controller
            SCSI ID: deadbeaf5:0
            SCSI SN: beaf50
            Size: 0 MB
            Online: Yes
            Removable media: No
            Backing store: No backing store
    Account information:
    ACL information:

二:在客户端上挂载前面模拟出的共享磁盘阵列

[root@db2 ~]# iscsiadm --mode discovery --type sendtargets --portal 192.168.123.10
192.168.123.10:3260,1 iqn.2012-07-04.com.yang.rac:fra
192.168.123.10:3260,1 iqn.2012-07-04.com.yang.rac:crs1
192.168.123.10:3260,1 iqn.2012-07-04.com.yang.rac:crs3
192.168.123.10:3260,1 iqn.2012-07-04.com.yang.rac:data
192.168.123.10:3260,1 iqn.2012-07-04.com.yang.rac:crs2

[root@db2 ~]# iscsiadm --mode node --targetname iqn.2012-07-04.com.yang.rac:crs1 --portal 192.168.123.10 --login
[root@db2 ~]# iscsiadm --mode node --targetname iqn.2012-07-04.com.yang.rac:crs2 --portal 192.168.123.10 --login
[root@db2 ~]# iscsiadm --mode node --targetname iqn.2012-07-04.com.yang.rac:crs3 --portal 192.168.123.10 --login
[root@db2 ~]# iscsiadm --mode node --targetname iqn.2012-07-04.com.yang.rac:data --portal 192.168.123.10 --login
[root@db2 ~]# iscsiadm --mode node --targetname iqn.2012-07-04.com.yang.rac:fra  --portal 192.168.123.10 --login

[root@db2 ~]# fdisk -l
Disk /dev/sda: 85.8 GB, 85899345920 bytes
255 heads, 63 sectors/track, 10443 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         523     4096575   82  Linux swap / Solaris
/dev/sda3             524       10443    79682400   83  Linux

Disk /dev/sdb: 2147 MB, 2147483648 bytes
67 heads, 62 sectors/track, 1009 cylinders
Units = cylinders of 4154 * 512 = 2126848 bytes

Disk /dev/sdb doesn't contain a valid partition table

Disk /dev/sdc: 2147 MB, 2147483648 bytes
67 heads, 62 sectors/track, 1009 cylinders
Units = cylinders of 4154 * 512 = 2126848 bytes

Disk /dev/sdc doesn't contain a valid partition table

Disk /dev/sdd: 2147 MB, 2147483648 bytes
67 heads, 62 sectors/track, 1009 cylinders
Units = cylinders of 4154 * 512 = 2126848 bytes

Disk /dev/sdd doesn't contain a valid partition table

Disk /dev/sde: 10.7 GB, 10737418240 bytes
64 heads, 32 sectors/track, 10240 cylinders
Units = cylinders of 2048 * 512 = 1048576 bytes

Disk /dev/sde doesn't contain a valid partition table

Disk /dev/sdf: 10.7 GB, 10737418240 bytes
64 heads, 32 sectors/track, 10240 cylinders
Units = cylinders of 2048 * 512 = 1048576 bytes

Disk /dev/sdf doesn't contain a valid partition table

三：开始配置udev

[root@db2 ~]# uname -r  //在本例中操作系统的版本位centos5.4 64bit
2.6.18-164.el5
[root@db2 ~]# lsb_release -a
LSB Version:    :core-3.1-amd64:core-3.1-ia32:core-3.1-noarch:graphics-3.1-amd64:graphics-3.1-ia32:graphics-3.1-noarch
Distributor ID: CentOS
Description:    CentOS release 5.4 (Final)
Release:        5.4
Codename:       Final

[root@db2 ~]# rpm -qa |grep udev
udev-095-14.21.el5

[root@db2 ~]# ps -ef |grep udev
root      4646     1  0 10:14 ?        00:00:00 /sbin/udevd -d
root      6023  3039  0 10:32 pts/0    00:00:00 grep udev

[root@db2 ~]# grep -v ^# /etc/udev/udev.conf  |grep -v ^$
udev_log="err"

[root@db2 ~]# scsi_id -g -u -s /block/sdb
S_beaf11
[root@db2 ~]# scsi_id -g -u -s /block/sdc
S_beaf12
[root@db2 ~]# scsi_id -g -u -s /block/sdd
S_beaf13
[root@db2 ~]# scsi_id -g -u -s /block/sde
S_beaf14
[root@db2 ~]# scsi_id -g -u -s /block/sdf
S_beaf15

[root@db2 ~]# cat /etc/udev/rules.d/99-raw.rules
KERNEL=="sd*", BUS=="scsi", PROGRAM=="/sbin/scsi_id -g -u -s %p", RESULT=="S_beaf11", NAME="asmdisk1", OWNER="grid",
GROUP="asmadmin", MODE="0660"
KERNEL=="sd*", BUS=="scsi", PROGRAM=="/sbin/scsi_id -g -u -s %p", RESULT=="S_beaf12", NAME="asmdisk2", OWNER="grid",
GROUP="asmadmin", MODE="0660"
KERNEL=="sd*", BUS=="scsi", PROGRAM=="/sbin/scsi_id -g -u -s %p", RESULT=="S_beaf13", NAME="asmdisk3", OWNER="grid",
GROUP="asmadmin", MODE="0660"
KERNEL=="sd*", BUS=="scsi", PROGRAM=="/sbin/scsi_id -g -u -s %p", RESULT=="S_beaf14", NAME="asmdisk4", OWNER="grid",
GROUP="asmadmin", MODE="0660"
KERNEL=="sd*", BUS=="scsi", PROGRAM=="/sbin/scsi_id -g -u -s %p", RESULT=="S_beaf15", NAME="asmdisk5", OWNER="grid",
GROUP="asmadmin", MODE="0660"

[root@db2 ~]# ll /dev/asm*
ls: /dev/asm*: No such file or directory
[root@db2 ~]# /sbin/udevcontrol reload_rules
[root@db2 ~]# /sbin/start_udev
Starting udev: [  OK  ]
[root@db2 ~]# ll /dev/asm*
brw-rw---- 1 grid asmadmin 8, 16 Jul  4 12:05 /dev/asmdisk1
brw-rw---- 1 grid asmadmin 8, 32 Jul  4 12:05 /dev/asmdisk2
brw-rw---- 1 grid asmadmin 8, 48 Jul  4 12:05 /dev/asmdisk3
brw-rw---- 1 grid asmadmin 8, 64 Jul  4 12:05 /dev/asmdisk4
brw-rw---- 1 grid asmadmin 8, 80 Jul  4 12:05 /dev/asmdisk5

备注：
1：在vmware中，scsi_id -g -u -s /block/sdb默认是不会出现uuid，需要修改vmx文件，添加disk.EnableUUID参数
2：/block/sdb实际上是个不存在的路径，实际绝对路径是/sys/block/sdb，但使用scsi_id命令的时候必须用/block/sdb路径

参考：
http://diznix.com/2011/05/21/the-case-of-vmware-and-the-missing-scsi-id/
http://space.itpub.net/14184018/viewspace-701675