在虚拟机上VM 添加一块共享磁盘方法 支持ORACLE 10G RAC .

因为原先的ASM共享磁盘容量小,无法装下归档日志和备份文件.所以决定增加一块磁盘.

1 在节点1增加一块虚拟磁盘 放在原来的共享目录上 取名为ASM4

     选择SCSI 1:5  注意放在SCSI总线1号上面排在其他盘后面,否则容易发生盘符改变

     mode=independent->Persistent

2  关闭虚拟机文件,然后用UEDIT打开 Red Hat Enterprise Linux 4.vmx 在文件最后

scsi1:5.present = "TRUE"
scsi1:5.fileName = "F:\sharkdisk\asm4.vmdk"

scsi1:5.mode = "independent-persistent"

可以看到成功添加了ASM4

在原来后面的共享磁盘添加一条

disk.locking = "false"
diskLib.dataCacheMaxSize = "0"
diskLib.dataCacheMaxReadAheadSize = "0"
diskLib.DataCacheMinReadAheadSize = "0"
diskLib.dataCachePageSize = "4096"
diskLib.maxUnsyncedWrites = "0"
-- scsi1.sharedBus = "VIRTUAL"  这条其他人添加的共享总线, 本人没有添加这行,也行!
scsi1:0.deviceType = "disk"
scsi1:1.deviceType = "disk"
scsi1:2.deviceType = "disk"
scsi1:3.deviceType = "disk"
scsi1:4.deviceType = "disk"
scsi1:5.deviceType = "disk"

3 节点2 添加已经存在的虚拟磁盘,在编辑机器上,选择磁盘,选择已经存在的磁盘 在共享目录上找到ASM4 并且设置下 SCSI 1:5 和independent=Persistent

4 关闭虚拟机文件,然后用UEDIT打开 Red Hat Enterprise Linux 4.vmx  添加 scsi1:5.deviceType = "disk"

5 启动节点1 切换到ROOT 用户下 fdisk 新磁盘

 [root@node1 ~]# fdisk -l

Disk /dev/sdh: 8589 MB, 8589934592 bytes
255 heads, 63 sectors/track, 1044 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

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

 [root@node1 ~]# fdisk /dev/sdh

[root@node1 ~]# fdisk /dev/sdh
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.

The number of cylinders for this disk is set to 1044.
There is nothing wrong with that, but this is larger than 1024,
and could in certain setups cause problems with:
1) software that runs at boot time (e.g., old versions of LILO)
2) booting and partitioning software from other OSs
   (e.g., DOS FDISK, OS/2 FDISK)
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)

Command (m for help): n                                                                              --新建分区
Command action
   e   extended
   p   primary partition (1-4)
p                                                                                                                              --主分区
Partition number (1-4): 1                                                                                    --分区号 1
First cylinder (1-1044, default 1): 1                                                                   --从柱面1开始
Last cylinder or +size or +sizeM or +sizeK (1-1044, default 1044): 1044   --到最后1个柱面
Command (m for help): w                                                                                   --保存分区
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.
[root@node1 ~]# 

[root@node1 ~]# /etc/init.d/oracleasm createdisk VOL4 /dev/sdh1
Marking disk "VOL4" as an ASM disk:                        [  OK  ]

[root@node1 ~]# /etc/init.d/oracleasm listdisks
VOL1
VOL2
VOL3
VOL4

6 启动节点2 分区被发现,同时ASM盘已经被找到了

[root@node2 ~]# fdisk -l
Disk /dev/sdh: 8589 MB, 8589934592 bytes
255 heads, 63 sectors/track, 1044 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sdh1               1        1044     8385898+  83  Linux

[root@node2 ~]# /etc/init.d/oracleasm listdisks
VOL1
VOL2
VOL3
VOL4