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 Physicalvolume /dev/sdb successfullycreated [root@db1~]#vgcreatedata/dev/sdb /dev/hdc:openfailed:Read-onlyfilesystem /dev/cdrom:openfailed:Read-onlyfilesystem Attempttoclosedevice'/dev/cdrom'whichisnotopen. Volumegroup data successfullycreated [root@db1~]#lvcreate-ncrs1-L2Gdata Logicalvolume crs1 created [root@db1~]#lvcreate-ncrs2-L2Gdata Logicalvolume crs2 created [root@db1~]#lvcreate-ncrs3-L2Gdata Logicalvolume crs3 created [root@db1~]#lvcreate-ndata-L10Gdata Logicalvolume data created [root@db1~]#lvcreate-nfra-L10Gdata Logicalvolume fra created [root@db1~]#lvs LVVGAttrLSizeOriginSnap%MoveLogCopy%Convert crs1data-wi-a-2.00G crs2data-wi-a-2.00G crs3data-wi-a-2.00G datadata-wi-a-10.00G fradata-wi-a-10.00G [root@db1~]#servicetgtdstart StartingSCSItargetdaemon:[OK] [root@db1~]#catiscsi.sh tgtadm--lldiscsi--opnew--modetarget--tid1-Tiqn.2012-07-04.com.yang.rac:crs1 tgtadm--lldiscsi--opnew--modetarget--tid2-Tiqn.2012-07-04.com.yang.rac:crs2 tgtadm--lldiscsi--opnew--modetarget--tid3-Tiqn.2012-07-04.com.yang.rac:crs3 tgtadm--lldiscsi--opnew--modetarget--tid4-Tiqn.2012-07-04.com.yang.rac:data tgtadm--lldiscsi--opnew--modetarget--tid5-Tiqn.2012-07-04.com.yang.rac:fra tgtadm--lldiscsi--opnew--modelogicalunit--tid1--lun1-b/dev/data/crs1 tgtadm--lldiscsi--opnew--modelogicalunit--tid1--lun2-b/dev/data/crs2 tgtadm--lldiscsi--opnew--modelogicalunit--tid1--lun3-b/dev/data/crs3 tgtadm--lldiscsi--opnew--modelogicalunit--tid1--lun4-b/dev/data/data tgtadm--lldiscsi--opnew--modelogicalunit--tid1--lun5-b/dev/data/fra tgtadm--lldiscsi--opbind--modetarget--tid1-IALL tgtadm--lldiscsi--opbind--modetarget--tid2-IALL tgtadm--lldiscsi--opbind--modetarget--tid3-IALL tgtadm--lldiscsi--opbind--modetarget--tid4-IALL tgtadm--lldiscsi--opbind--modetarget--tid5-IALL [root@db1~]#tgtadm--lldiscsi-oshow-mtarget [root@db1~]#shiscsi.sh [root@db1~]#tgtadm--lldiscsi-oshow-mtarget Target1:iqn.2012-07-04.com.yang.rac:crs1 Systeminformation: Driver:iscsi State:ready I_Tnexusinformation: LUNinformation: LUN:0 Type:controller SCSIID:deadbeaf1:0 SCSISN:beaf10 Size:0MB Online:Yes Removablemedia:No Backingstore:Nobackingstore LUN:1 Type:disk SCSIID:deadbeaf1:1 SCSISN:beaf11 Size:2147MB Online:Yes Removablemedia:No Backingstore:/dev/data/crs1 LUN:2 Type:disk SCSIID:deadbeaf1:2 SCSISN:beaf12 Size:2147MB Online:Yes Removablemedia:No Backingstore:/dev/data/crs2 LUN:3 Type:disk SCSIID:deadbeaf1:3 SCSISN:beaf13 Size:2147MB Online:Yes Removablemedia:No Backingstore:/dev/data/crs3 LUN:4 Type:disk SCSIID:deadbeaf1:4 SCSISN:beaf14 Size:10737MB Online:Yes Removablemedia:No Backingstore:/dev/data/data LUN:5 Type:disk SCSIID:deadbeaf1:5 SCSISN:beaf15 Size:10737MB Online:Yes Removablemedia:No Backingstore:/dev/data/fra Accountinformation: ACLinformation: ALL Target2:iqn.2012-07-04.com.yang.rac:crs2 Systeminformation: Driver:iscsi State:ready I_Tnexusinformation: LUNinformation: LUN:0 Type:controller SCSIID:deadbeaf2:0 SCSISN:beaf20 Size:0MB Online:Yes Removablemedia:No Backingstore:Nobackingstore Accountinformation: ACLinformation: Target3:iqn.2012-07-04.com.yang.rac:crs3 Systeminformation: Driver:iscsi State:ready I_Tnexusinformation: LUNinformation: LUN:0 Type:controller SCSIID:deadbeaf3:0 SCSISN:beaf30 Size:0MB Online:Yes Removablemedia:No Backingstore:Nobackingstore Accountinformation: ACLinformation: Target4:iqn.2012-07-04.com.yang.rac:data Systeminformation: Driver:iscsi State:ready I_Tnexusinformation: LUNinformation: LUN:0 Type:controller SCSIID:deadbeaf4:0 SCSISN:beaf40 Size:0MB Online:Yes Removablemedia:No Backingstore:Nobackingstore Accountinformation: ACLinformation: Target5:iqn.2012-07-04.com.yang.rac:fra Systeminformation: Driver:iscsi State:ready I_Tnexusinformation: LUNinformation: LUN:0 Type:controller SCSIID:deadbeaf5:0 SCSISN:beaf50 Size:0MB Online:Yes Removablemedia:No Backingstore:Nobackingstore Accountinformation: ACLinformation:
二:在客户端上挂载前面模拟出的共享磁盘阵列
[root@db2~]#iscsiadm--modediscovery--typesendtargets--portal192.168.123.10 192.168.123.10:3260,1iqn.2012-07-04.com.yang.rac:fra 192.168.123.10:3260,1iqn.2012-07-04.com.yang.rac:crs1 192.168.123.10:3260,1iqn.2012-07-04.com.yang.rac:crs3 192.168.123.10:3260,1iqn.2012-07-04.com.yang.rac:data 192.168.123.10:3260,1iqn.2012-07-04.com.yang.rac:crs2 [root@db2~]#iscsiadm--modenode--targetnameiqn.2012-07-04.com.yang.rac:crs1--portal192.168.123.10--login [root@db2~]#iscsiadm--modenode--targetnameiqn.2012-07-04.com.yang.rac:crs2--portal192.168.123.10--login [root@db2~]#iscsiadm--modenode--targetnameiqn.2012-07-04.com.yang.rac:crs3--portal192.168.123.10--login [root@db2~]#iscsiadm--modenode--targetnameiqn.2012-07-04.com.yang.rac:data--portal192.168.123.10--login [root@db2~]#iscsiadm--modenode--targetnameiqn.2012-07-04.com.yang.rac:fra--portal192.168.123.10--login [root@db2~]#fdisk-l Disk/dev/sda:85.8GB,85899345920bytes 255heads,63sectors/track,10443cylinders Units=cylindersof16065*512=8225280bytes DeviceBootStartEndBlocksIdSystem /dev/sda1*11310439183Linux /dev/sda214523409657582Linuxswap/Solaris /dev/sda3524104437968240083Linux Disk/dev/sdb:2147MB,2147483648bytes 67heads,62sectors/track,1009cylinders Units=cylindersof4154*512=2126848bytes Disk/dev/sdbdoesn'tcontainavalidpartitiontable Disk/dev/sdc:2147MB,2147483648bytes 67heads,62sectors/track,1009cylinders Units=cylindersof4154*512=2126848bytes Disk/dev/sdcdoesn'tcontainavalidpartitiontable Disk/dev/sdd:2147MB,2147483648bytes 67heads,62sectors/track,1009cylinders Units=cylindersof4154*512=2126848bytes Disk/dev/sdddoesn'tcontainavalidpartitiontable Disk/dev/sde:10.7GB,10737418240bytes 64heads,32sectors/track,10240cylinders Units=cylindersof2048*512=1048576bytes Disk/dev/sdedoesn'tcontainavalidpartitiontable Disk/dev/sdf:10.7GB,10737418240bytes 64heads,32sectors/track,10240cylinders Units=cylindersof2048*512=1048576bytes Disk/dev/sdfdoesn'tcontainavalidpartitiontable
三：开始配置udev
[root@db2~]#uname-r//在本例中操作系统的版本位centos5.464bit 2.6.18-164.el5 [root@db2~]#lsb_release-a LSBVersion::core-3.1-amd64:core-3.1-ia32:core-3.1-noarch:graphics-3.1-amd64:graphics-3.1-ia32:graphics-3.1-noarch DistributorID:CentOS Description:CentOSrelease5.4(Final) Release:5.4 Codename:Final [root@db2~]#rpm-qa|grepudev udev-095-14.21.el5 [root@db2~]#ps-ef|grepudev root46461010:14?00:00:00/sbin/udevd-d root60233039010:32pts/000:00:00grepudev [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*:Nosuchfileordirectory [root@db2~]#/sbin/udevcontrolreload_rules [root@db2~]#/sbin/start_udev Startingudev:[OK] [root@db2~]#ll/dev/asm* brw-rw----1gridasmadmin8,16Jul412:05/dev/asmdisk1 brw-rw----1gridasmadmin8,32Jul412:05/dev/asmdisk2 brw-rw----1gridasmadmin8,48Jul412:05/dev/asmdisk3 brw-rw----1gridasmadmin8,64Jul412:05/dev/asmdisk4 brw-rw----1gridasmadmin8,80Jul412:05/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
勤奋，它是一块可以吸引到一切美好事物的天然磁石，它比黄金珍贵，
