ASM Metadata Dump Utility，即ASM元数据导出工具，它的简写amdu更被人所熟知，常被Oracle技术支持人员和Oracle开发人员用来诊断和解决ASM故障。它能输出ASM的元数据信息并且从ASM磁盘组中抽取元数据和数据文件。 amdu工具不依赖于ASM实例或者ASM磁盘组的状态，所以它能在ASM实例关闭和磁盘组未挂载的情况下正常使用，它甚至能在ASM磁盘出现故障或者不可见的场景下使用。
使用amdu从mounted磁盘组中抽取控制文件
在接下来的第一个例子中，我们将以一个处于mount状态的磁盘组为例，使用amdu提取数据库jyrac的一个控制文件。通过asmcmd的find命令结合–type参数，指定查找文件类型为controlfile的文件，以下输出列出了所有找到的控制文件的位置
[grid@jyrac1 ~]$ asmcmd find --type controlfile + "*" +DATADG/JYRAC/CONTROLFILE/current.257.930412709
以上输出我们可以知道，在DATADG磁盘组存放了JYRAC数据库控制文件的一个副本。这里以提取DATA磁盘组的current.257.930412709控制文件为例。首先我们看下DATA磁盘组有哪些磁盘：
[grid@jyrac1 ~]$ asmcmd lsdsk -G DATADG Path /dev/raw/raw10 /dev/raw/raw11 /dev/raw/raw3 /dev/raw/raw4
DATADG磁盘组共有四块磁盘/dev/raw/raw10,/dev/raw/raw11,/dev/raw/raw3和/dev/raw/raw4，如果名字都是以ORCL为前缀，那么磁盘是ASMLIB磁盘。严格意义上，并不需要知道具体的磁盘名，只需要查找ASM_DISKSTRING参数值所定义的目录即可。我们接着用amdu工具将控制文件从DATA磁盘组提取到文件系统上：
[grid@jyrac1 ~]$ amdu -diskstring="/dev/raw/*" -extract DATADG.257 -output control.257 -noreport -nodir AMDU-00204: Disk N0003 is in currently mounted diskgroup DATADG AMDU-00201: Disk N0003: '/dev/raw/raw11' AMDU-00204: Disk N0009 is in currently mounted diskgroup DATADG AMDU-00201: Disk N0009: '/dev/raw/raw4' AMDU-00204: Disk N0008 is in currently mounted diskgroup DATADG AMDU-00201: Disk N0008: '/dev/raw/raw3' [grid@jyrac1 ~]$ ls -lrt control.257 -rw-r--r-- 1 grid oinstall 18595840 Jan 5 16:03 control.257
此命令相关参数的含义如下：
diskstring: 使用磁盘的全路径或者是ASM_DISKSTRING参数值
extract: 磁盘组名.ASM文件序号
output:提取的输出文件（当前目录下）
noreport:不输出amdu的执行过程
nodir:不创建dump目录
使用amdu从dismounted磁盘组中抽取数据文件
上例中从一个已挂载的磁盘组上提取控制文件的过程简单明了。但在实际工作中，可能有客户提出要求从一个未挂载的磁盘组中提取一个重要数据文件，同时并不知道数据文件名，也没有备份。以下是一个具体的例子，演示了整个操作和分析过程。本例的目标是使用amdu工具从一个不能被挂载的DATA磁盘组中提取一个数据文件，文件名字中包含NSA。这首先意味着在这里sqlplus和asmcmd工具都不能使用。首先使用amdu工具对DATA磁盘组做一份元数据的完整dump。
[grid@jyrac1 ~]$ amdu -dump DATADG -noimage amdu_2017_01_05_16_09_47/ AMDU-00204: Disk N0003 is in currently mounted diskgroup DATADG AMDU-00201: Disk N0003: '/dev/raw/raw11' AMDU-00204: Disk N0009 is in currently mounted diskgroup DATADG AMDU-00201: Disk N0009: '/dev/raw/raw4' AMDU-00204: Disk N0008 is in currently mounted diskgroup DATADG AMDU-00201: Disk N0008: '/dev/raw/raw3' [grid@jyrac1 ~]$ cd amdu_2017_01_05_16_09_47/ [grid@jyrac1 amdu_2017_01_05_16_09_47]$ [grid@jyrac1 amdu_2017_01_05_16_09_47]$ ls -lrt total 44 -rw-r--r-- 1 grid oinstall 16222 Jan 5 16:09 report.txt -rw-r--r-- 1 grid oinstall 27520 Jan 5 16:09 DATADG.map
在本例中amdu创建了dump目录并产生了两个文件。report.txt文件包含主机、amdu命令及使用的参数、DATADG磁盘组可能的成员磁盘和这些磁盘上的AU信息。report.txt文件内容如下：
[grid@jyrac1 amdu_2017_01_05_16_09_47]$ more report.txt
-*-amdu-*-
******************************* AMDU Settings ********************************
ORACLE_HOME = /u01/app/product/11.2.0/crs
System name: Linux
Node name: jyrac1
Release: 2.6.18-164.el5
Version: #1 SMP Tue Aug 18 15:51:48 EDT 2009
Machine: x86_64
amdu run: 05-JAN-17 16:09:47
Endianess: 1
--------------------------------- Operations ---------------------------------
-dump DATADG
------------------------------- Disk Selection -------------------------------
-diskstring ''
------------------------------ Reading Control -------------------------------
------------------------------- Output Control -------------------------------
-noimage
********************************* DISCOVERY **********************************
----------------------------- DISK REPORT N0001 ------------------------------
Disk Path: /dev/raw/raw1
Unique Disk ID:
Disk Label:
Physical Sector Size: 512 bytes
Disk Size: 5120 megabytes
Group Name: CRSDG
Disk Name: CRSDG_0000
Failure Group Name: CRSDG_0000
Disk Number: 0
Header Status: 3
Disk Creation Time: 2016/11/22 18:24:35.358000
Last Mount Time: 2016/12/14 17:02:09.327000
Compatibility Version: 0x0b200000(11020000)
Disk Sector Size: 512 bytes
Disk size in AUs: 5120 AUs
Group Redundancy: 1
Metadata Block Size: 4096 bytes
AU Size: 1048576 bytes
Stride: 113792 AUs
Group Creation Time: 2016/11/22 18:24:35.079000
File 1 Block 1 location: AU 2
OCR Present: YES
----------------------------- DISK REPORT N0002 ------------------------------
Disk Path: /dev/raw/raw10
Unique Disk ID:
Disk Label:
Physical Sector Size: 512 bytes
Disk Size: 5120 megabytes
Group Name: DATADG
Disk Name: DATADG_0000
Failure Group Name: DATADG_0000
Disk Number: 3
Header Status: 3
Disk Creation Time: 2016/12/12 15:36:39.090000
Last Mount Time: 2017/01/03 11:54:18.454000
Compatibility Version: 0x0b200000(11020000)
Disk Sector Size: 512 bytes
Disk size in AUs: 5120 AUs
Group Redundancy: 2
Metadata Block Size: 4096 bytes
AU Size: 1048576 bytes
Stride: 113792 AUs
Group Creation Time: 2016/12/12 15:36:38.488000
File 1 Block 1 location: AU 0
OCR Present: NO
----------------------------- DISK REPORT N0003 ------------------------------
Disk Path: /dev/raw/raw11
Unique Disk ID:
Disk Label:
Physical Sector Size: 512 bytes
Disk Size: 5120 megabytes
Group Name: DATADG
Disk Name: DATADG_0001
Failure Group Name: DATADG_0001
Disk Number: 0
Header Status: 3
Disk Creation Time: 2016/12/12 15:36:39.090000
Last Mount Time: 2016/12/14 17:02:10.127000
Compatibility Version: 0x0b200000(11020000)
Disk Sector Size: 512 bytes
Disk size in AUs: 5120 AUs
Group Redundancy: 2
Metadata Block Size: 4096 bytes
AU Size: 1048576 bytes
Stride: 113792 AUs
Group Creation Time: 2016/12/12 15:36:38.488000
File 1 Block 1 location: AU 2
OCR Present: NO
----------------------------- DISK REPORT N0004 ------------------------------
Disk Path: /dev/raw/raw12
Unique Disk ID:
Disk Label:
Physical Sector Size: 512 bytes
Disk Size: 5120 megabytes
Group Name: USD
Disk Name: USD_0001
Failure Group Name: USD_0001
Disk Number: 1
Header Status: 3
Disk Creation Time: 2016/12/30 14:58:59.434000
Last Mount Time: 2017/01/03 09:57:50.397000
Compatibility Version: 0x0b200000(11020000)
Disk Sector Size: 512 bytes
Disk size in AUs: 5120 AUs
Group Redundancy: 2
Metadata Block Size: 4096 bytes
AU Size: 1048576 bytes
Stride: 113792 AUs
Group Creation Time: 2016/12/30 14:58:59.213000
File 1 Block 1 location: AU 1344
OCR Present: NO
----------------------------- DISK REPORT N0005 ------------------------------
Disk Path: /dev/raw/raw13
Unique Disk ID:
Disk Label:
Physical Sector Size: 512 bytes
Disk Size: 5120 megabytes
Group Name: TESTDG
Disk Name: TESTDG_0004
Failure Group Name: TESTDG_0004
Disk Number: 4
Header Status: 4
Disk Creation Time: 2016/12/28 16:04:46.242000
Last Mount Time: 2016/12/28 16:04:57.102000
Compatibility Version: 0x0a100000(10010000)
Disk Sector Size: 512 bytes
Disk size in AUs: 5120 AUs
Group Redundancy: 2
Metadata Block Size: 4096 bytes
AU Size: 1048576 bytes
Stride: 113792 AUs
Group Creation Time: 2016/12/28 16:04:45.574000
File 1 Block 1 location: AU 0
OCR Present: NO
----------------------------- DISK REPORT N0006 ------------------------------
Disk Path: /dev/raw/raw14
Unique Disk ID:
Disk Label:
Physical Sector Size: 512 bytes
Disk Size: 5120 megabytes
Group Name: TESTDG
Disk Name: TESTDG_0005
Failure Group Name: TESTDG_0005
Disk Number: 5
Header Status: 4
Disk Creation Time: 2016/12/28 16:04:46.242000
Last Mount Time: 2016/12/28 16:04:57.102000
Compatibility Version: 0x0a100000(10010000)
Disk Sector Size: 512 bytes
Disk size in AUs: 5120 AUs
Group Redundancy: 2
Metadata Block Size: 4096 bytes
AU Size: 1048576 bytes
Stride: 113792 AUs
Group Creation Time: 2016/12/28 16:04:45.574000
File 1 Block 1 location: AU 0
OCR Present: NO
----------------------------- DISK REPORT N0007 ------------------------------
Disk Path: /dev/raw/raw2
Unique Disk ID:
Disk Label:
Physical Sector Size: 512 bytes
Disk Size: 5120 megabytes
Group Name: ARCHDG
Disk Name: ARCHDG_0000
Failure Group Name: ARCHDG_0000
Disk Number: 0
Header Status: 3
Disk Creation Time: 2016/11/22 19:18:27.892000
Last Mount Time: 2016/12/14 17:02:08.754000
Compatibility Version: 0x0b200000(11020000)
Disk Sector Size: 512 bytes
Disk size in AUs: 5120 AUs
Group Redundancy: 2
Metadata Block Size: 4096 bytes
AU Size: 1048576 bytes
Stride: 113792 AUs
Group Creation Time: 2016/11/22 19:18:27.619000
File 1 Block 1 location: AU 2
OCR Present: NO
----------------------------- DISK REPORT N0008 ------------------------------
Disk Path: /dev/raw/raw3
Unique Disk ID:
Disk Label:
Physical Sector Size: 512 bytes
Disk Size: 5120 megabytes
Group Name: DATADG
Disk Name: DATADG_0002
Failure Group Name: DATADG_0002
Disk Number: 2
Header Status: 3
Disk Creation Time: 2016/12/12 15:36:39.090000
Last Mount Time: 2016/12/14 17:02:10.127000
Compatibility Version: 0x0b200000(11020000)
Disk Sector Size: 512 bytes
Disk size in AUs: 5120 AUs
Group Redundancy: 2
Metadata Block Size: 4096 bytes
AU Size: 1048576 bytes
Stride: 113792 AUs
Group Creation Time: 2016/12/12 15:36:38.488000
File 1 Block 1 location: AU 2
OCR Present: NO
----------------------------- DISK REPORT N0009 ------------------------------
Disk Path: /dev/raw/raw4
Unique Disk ID:
Disk Label:
Physical Sector Size: 512 bytes
Disk Size: 5120 megabytes
Group Name: DATADG
Disk Name: DATADG_0003
Failure Group Name: DATADG_0003
Disk Number: 1
Header Status: 3
Disk Creation Time: 2016/12/12 15:36:39.090000
Last Mount Time: 2016/12/14 17:02:10.127000
Compatibility Version: 0x0b200000(11020000)
Disk Sector Size: 512 bytes
Disk size in AUs: 5120 AUs
Group Redundancy: 2
Metadata Block Size: 4096 bytes
AU Size: 1048576 bytes
Stride: 113792 AUs
Group Creation Time: 2016/12/12 15:36:38.488000
File 1 Block 1 location: AU 2
OCR Present: NO
----------------------------- DISK REPORT N0010 ------------------------------
Disk Path: /dev/raw/raw5
Unique Disk ID:
Disk Label:
Physical Sector Size: 512 bytes
Disk Size: 5120 megabytes
Group Name: ACFS
Disk Name: ACFS_0000
Failure Group Name: ACFS_0000
Disk Number: 0
Header Status: 3
Disk Creation Time: 2016/12/30 09:09:30.242000
Last Mount Time: 2016/12/30 09:09:41.395000
Compatibility Version: 0x0b200000(11020000)
Disk Sector Size: 512 bytes
Disk size in AUs: 5120 AUs
Group Redundancy: 2
Metadata Block Size: 4096 bytes
AU Size: 1048576 bytes
Stride: 113792 AUs
Group Creation Time: 2016/12/30 09:09:29.830000
File 1 Block 1 location: AU 2
OCR Present: NO
----------------------------- DISK REPORT N0011 ------------------------------
Disk Path: /dev/raw/raw6
Unique Disk ID:
Disk Label:
Physical Sector Size: 512 bytes
Disk Size: 5120 megabytes
Group Name: ACFS
Disk Name: ACFS_0001
Failure Group Name: ACFS_0001
Disk Number: 1
Header Status: 3
Disk Creation Time: 2016/12/30 09:09:30.242000
Last Mount Time: 2016/12/30 09:09:41.395000
Compatibility Version: 0x0b200000(11020000)
Disk Sector Size: 512 bytes
Disk size in AUs: 5120 AUs
Group Redundancy: 2
Metadata Block Size: 4096 bytes
AU Size: 1048576 bytes
Stride: 113792 AUs
Group Creation Time: 2016/12/30 09:09:29.830000
File 1 Block 1 location: AU 2
OCR Present: NO
----------------------------- DISK REPORT N0012 ------------------------------
Disk Path: /dev/raw/raw7
Unique Disk ID:
Disk Label:
Physical Sector Size: 512 bytes
Disk Size: 5120 megabytes
Group Name: USD
Disk Name: USD_0000
Failure Group Name: USD_0000
Disk Number: 0
Header Status: 3
Disk Creation Time: 2016/12/30 14:58:59.434000
Last Mount Time: 2016/12/30 14:59:10.816000
Compatibility Version: 0x0b200000(11020000)
Disk Sector Size: 512 bytes
Disk size in AUs: 5120 AUs
Group Redundancy: 2
Metadata Block Size: 4096 bytes
AU Size: 1048576 bytes
Stride: 113792 AUs
Group Creation Time: 2016/12/30 14:58:59.213000
File 1 Block 1 location: AU 2
OCR Present: NO
----------------------------- DISK REPORT N0013 ------------------------------
Disk Path: /dev/raw/raw8
Unique Disk ID:
Disk Label:
Physical Sector Size: 512 bytes
Disk Size: 5120 megabytes
Group Name: CRSDG
Disk Name: CRSDG_0001
Failure Group Name: CRSDG_0001
Disk Number: 1
Header Status: 3
Disk Creation Time: 2016/11/22 18:24:35.358000
Last Mount Time: 2016/12/14 17:02:09.327000
Compatibility Version: 0x0b200000(11020000)
Disk Sector Size: 512 bytes
Disk size in AUs: 5120 AUs
Group Redundancy: 1
Metadata Block Size: 4096 bytes
AU Size: 1048576 bytes
Stride: 113792 AUs
Group Creation Time: 2016/11/22 18:24:35.079000
File 1 Block 1 location: AU 0
OCR Present: NO
----------------------------- DISK REPORT N0014 ------------------------------
Disk Path: /dev/raw/raw9
Unique Disk ID:
Disk Label:
Physical Sector Size: 512 bytes
Disk Size: 5120 megabytes
Group Name: ARCHDG
Disk Name: ARCHDG_0001
Failure Group Name: ARCHDG_0001
Disk Number: 1
Header Status: 3
Disk Creation Time: 2016/11/22 19:18:27.892000
Last Mount Time: 2016/12/14 17:02:08.754000
Compatibility Version: 0x0b200000(11020000)
Disk Sector Size: 512 bytes
Disk size in AUs: 5120 AUs
Group Redundancy: 2
Metadata Block Size: 4096 bytes
AU Size: 1048576 bytes
Stride: 113792 AUs
Group Creation Time: 2016/11/22 19:18:27.619000
File 1 Block 1 location: AU 2
OCR Present: NO
***************** Slept for 6 seconds waiting for heartbeats *****************
************************* SCANNING DISKGROUP DATADG **************************
Creation Time: 2016/12/12 15:36:38.488000
Disks Discovered: 4
Redundancy: 2
AU Size: 1048576 bytes
Metadata Block Size: 4096 bytes
Physical Sector Size: 512 bytes
Metadata Stride: 113792 AU
Duplicate Disk Numbers: 0
---------------------------- SCANNING DISK N0003 -----------------------------
Disk N0003: '/dev/raw/raw11'
AMDU-00204: Disk N0003 is in currently mounted diskgroup DATADG
AMDU-00201: Disk N0003: '/dev/raw/raw11'
** HEARTBEAT DETECTED **
Allocated AU's: 1737
Free AU's: 3383
AU's read for dump: 83
Block images saved: 19712
Map lines written: 83
Heartbeats seen: 1
Corrupt metadata blocks: 0
Corrupt AT blocks: 0
---------------------------- SCANNING DISK N0009 -----------------------------
Disk N0009: '/dev/raw/raw4'
AMDU-00204: Disk N0009 is in currently mounted diskgroup DATADG
AMDU-00201: Disk N0009: '/dev/raw/raw4'
** HEARTBEAT DETECTED **
Allocated AU's: 1734
Free AU's: 3386
AU's read for dump: 85
Block images saved: 20488
Map lines written: 85
Heartbeats seen: 1
Corrupt metadata blocks: 0
Corrupt AT blocks: 0
---------------------------- SCANNING DISK N0008 -----------------------------
Disk N0008: '/dev/raw/raw3'
AMDU-00204: Disk N0008 is in currently mounted diskgroup DATADG
AMDU-00201: Disk N0008: '/dev/raw/raw3'
** HEARTBEAT DETECTED **
Allocated AU's: 1733
Free AU's: 3387
AU's read for dump: 89
Block images saved: 21256
Map lines written: 89
Heartbeats seen: 1
Corrupt metadata blocks: 0
Corrupt AT blocks: 0
---------------------------- SCANNING DISK N0002 -----------------------------
Disk N0002: '/dev/raw/raw10'
Allocated AU's: 1740
Free AU's: 3380
AU's read for dump: 87
Block images saved: 20487
Map lines written: 87
Heartbeats seen: 0
Corrupt metadata blocks: 0
Corrupt AT blocks: 0
------------------------ SUMMARY FOR DISKGROUP DATADG ------------------------
Allocated AU's: 6944
Free AU's: 13536
AU's read for dump: 344
Block images saved: 81943
Map lines written: 344
Heartbeats seen: 3
Corrupt metadata blocks: 0
Corrupt AT blocks: 0
******************************* END OF REPORT ********************************
[grid@jyrac1 amdu_2017_01_05_16_09_47]$ more DATADG.map
...
N0008 D0002 R00 A00000069 F00000003 I0 E00000241 U00 C00256 S0000 B0000000000
N0008 D0002 R00 A00000070 F00000003 I0 E00000244 U00 C00256 S0000 B0000000000
N0008 D0002 R00 A00000071 F00000003 I0 E00000248 U00 C00256 S0000 B0000000000
N0008 D0002 R00 A00000072 F00000003 I0 E00000249 U00 C00256 S0000 B0000000000
N0008 D0002 R00 A00000073 F00000004 I0 E00000012 U00 C00000 S0000 B0000000000
N0008 D0002 R00 A00000074 F00000004 I0 E00000017 U00 C00000 S0000 B0000000000
N0008 D0002 R00 A00000075 F00000004 I0 E00000019 U00 C00000 S0000 B0000000000
N0008 D0002 R00 A00000076 F00000004 I0 E00000022 U00 C00000 S0000 B0000000000
N0008 D0002 R00 A00000077 F00000001 I0 E00000004 U00 C00256 S0000 B0000000000
N0008 D0002 R00 A00000094 F00000257 I1 E00000002 U00 C00256 S0000 B0000000000
N0008 D0002 R00 A00000111 F00000258 I1 E00000001 U00 C00256 S0000 B0000000000
N0008 D0002 R00 A00000641 F00000259 I1 E00000000 U00 C00256 S0000 B0000000000
N0008 D0002 R00 A00001022 F00000260 I1 E00000001 U00 C00256 S0000 B0000000000
N0008 D0002 R00 A00001197 F00000261 I1 E00000002 U00 C00256 S0000 B0000000000
N0008 D0002 R00 A00001272 F00000262 I1 E00000000 U00 C00256 S0000 B0000000000
N0008 D0002 R00 A00001328 F00000264 I1 E00000000 U00 C00256 S0000 B0000000000
N0008 D0002 R00 A00001356 F00000265 I1 E00000001 U00 C00256 S0000 B0000000000
N0008 D0002 R00 A00001380 F00000266 I1 E00000000 U00 C00256 S0000 B0000000000
N0008 D0002 R00 A00001453 F00000270 I1 E00000000 U00 C00256 S0000 B0000000000
N0008 D0002 R00 A00001707 F00000012 I0 E00000001 U00 C00256 S0000 B0000000000
...
上面感觉有价值的内容是A和F起始的两列。比如，A00000094代表本行是关于AU 94. F00000257代表本行与序号257的ASM文件相关。重新回到查找NSA数据文件的目标。ASM序号6的元数据文件是alias别名目录，这是查找目标的起点。通过DATADG.map文件，能找到序号6的ASM元数据文件的所有AU。
[grid@jyrac1 amdu_2017_01_05_16_09_47]$ grep F00000006 DATADG.map N0009 D0001 R00 A00000036 F00000006 I0 E00000002 U00 C00256 S0000 B0000000000 N0008 D0002 R00 A00000038 F00000006 I0 E00000000 U00 C00256 S0000 B0000000000 N0002 D0003 R00 A00000037 F00000006 I0 E00000001 U00 C00256 S0000 B0000000000
通过查找定位到与该元数据文件相关的AU记录有三行。同时别名目录元数据文件存放在磁盘1(D0001)的AU 36(A00000036),磁盘2(D0002)的AU 38(A00000038)和磁盘3(D0003)的AU 37(A00000037)。 从前面report.txt的记录中知道，磁盘1指的是’/dev/raw/raw4’并且它的AU大小是1MB。通过kfed工具来查看alias目录文件。
[grid@jyrac1 amdu_2017_01_05_16_09_47]$ kfed read /dev/raw/raw4 aun=36 | more kfbh.endian: 1 ; 0x000: 0x01 kfbh.hard: 130 ; 0x001: 0x82 kfbh.type: 11 ; 0x002: KFBTYP_ALIASDIR kfbh.datfmt: 1 ; 0x003: 0x01 kfbh.block.blk: 0 ; 0x004: blk=0 kfbh.block.obj: 6 ; 0x008: file=6 kfbh.check: 2235498606 ; 0x00c: 0x853f006e kfbh.fcn.base: 3565 ; 0x010: 0x00000ded kfbh.fcn.wrap: 0 ; 0x014: 0x00000000 kfbh.spare1: 0 ; 0x018: 0x00000000 kfbh.spare2: 0 ; 0x01c: 0x00000000 kffdnd.bnode.incarn: 1 ; 0x000: A=1 NUMM=0x0 kffdnd.bnode.frlist.number: 4294967295 ; 0x004: 0xffffffff kffdnd.bnode.frlist.incarn: 0 ; 0x008: A=0 NUMM=0x0 kffdnd.overfl.number: 4294967295 ; 0x00c: 0xffffffff kffdnd.overfl.incarn: 0 ; 0x010: A=0 NUMM=0x0 kffdnd.parent.number: 0 ; 0x014: 0x00000000 kffdnd.parent.incarn: 1 ; 0x018: A=1 NUMM=0x0 kffdnd.fstblk.number: 0 ; 0x01c: 0x00000000 kffdnd.fstblk.incarn: 1 ; 0x020: A=1 NUMM=0x0 kfade[0].entry.incarn: 1 ; 0x024: A=1 NUMM=0x0 kfade[0].entry.hash: 2990280982 ; 0x028: 0xb23c1116 kfade[0].entry.refer.number: 1 ; 0x02c: 0x00000001 kfade[0].entry.refer.incarn: 1 ; 0x030: A=1 NUMM=0x0 kfade[0].name: JYRAC ; 0x034: length=5 kfade[0].fnum: 4294967295 ; 0x064: 0xffffffff kfade[0].finc: 4294967295 ; 0x068: 0xffffffff kfade[0].flags: 8 ; 0x06c: U=0 S=0 S=0 U=1 F=0 kfade[0].ub1spare: 0 ; 0x06d: 0x00 kfade[0].ub2spare: 0 ; 0x06e: 0x0000 kfade[1].entry.incarn: 1 ; 0x070: A=1 NUMM=0x0 kfade[1].entry.hash: 3585957073 ; 0x074: 0xd5bd5cd1 kfade[1].entry.refer.number: 9 ; 0x078: 0x00000009 kfade[1].entry.refer.incarn: 1 ; 0x07c: A=1 NUMM=0x0 kfade[1].name: DB_UNKNOWN ; 0x080: length=10 kfade[1].fnum: 4294967295 ; 0x0b0: 0xffffffff kfade[1].finc: 4294967295 ; 0x0b4: 0xffffffff kfade[1].flags: 4 ; 0x0b8: U=0 S=0 S=1 U=0 F=0 kfade[1].ub1spare: 0 ; 0x0b9: 0x00 kfade[1].ub2spare: 0 ; 0x0ba: 0x0000 kfade[2].entry.incarn: 3 ; 0x0bc: A=1 NUMM=0x1 kfade[2].entry.hash: 1585230659 ; 0x0c0: 0x5e7cb343 kfade[2].entry.refer.number: 4294967295 ; 0x0c4: 0xffffffff kfade[2].entry.refer.incarn: 0 ; 0x0c8: A=0 NUMM=0x0 ...
kfed的输出信息中kfbh.type验证了这是一个alias目录文件。下一步查找名字包含SYS的数据文件
[grid@jyrac1 amdu_2017_01_05_16_09_47]$ vi getfilename.sh for (( i=0; i<256; i++ )) do kfed read /dev/raw/raw4 aun=36 blkn=$i | grep -1 SYS done [grid@jyrac1 amdu_2017_01_05_16_09_47]$ chmod 777 getfilename.sh [grid@jyrac1 amdu_2017_01_05_16_09_47]$ ./getfilename.sh kfade[0].entry.refer.incarn: 0 ; 0x030: A=0 NUMM=0x0 kfade[0].name: SYSAUX ; 0x034: length=6 kfade[0].fnum: 258 ; 0x064: 0x00000102 -- kfade[1].entry.refer.incarn: 0 ; 0x07c: A=0 NUMM=0x0 kfade[1].name: SYSTEM ; 0x080: length=6 kfade[1].fnum: 259 ; 0x0b0: 0x00000103
名字包含SYS的数据文件是SYSTEM,SYSAUX，它们的ASM文件序号是258,259.接下来可以进一步提取数据文件
[grid@jyrac1 amdu_2017_01_05_16_09_47]$ amdu -diskstring="/dev/raw/*" -extract DATADG.258 -output SYSAUX.258 -noreport -nodir AMDU-00204: Disk N0003 is in currently mounted diskgroup DATADG AMDU-00201: Disk N0003: '/dev/raw/raw11' AMDU-00204: Disk N0009 is in currently mounted diskgroup DATADG AMDU-00201: Disk N0009: '/dev/raw/raw4' AMDU-00204: Disk N0008 is in currently mounted diskgroup DATADG AMDU-00201: Disk N0008: '/dev/raw/raw3' [grid@jyrac1 amdu_2017_01_05_16_09_47]$ amdu -diskstring="/dev/raw/*" -extract DATADG.259 -output SYSTEM.259 -noreport -nodir AMDU-00204: Disk N0003 is in currently mounted diskgroup DATADG AMDU-00201: Disk N0003: '/dev/raw/raw11' AMDU-00204: Disk N0009 is in currently mounted diskgroup DATADG AMDU-00201: Disk N0009: '/dev/raw/raw4' AMDU-00204: Disk N0008 is in currently mounted diskgroup DATADG AMDU-00201: Disk N0008: '/dev/raw/raw3' [grid@jyrac1 amdu_2017_01_05_16_09_47]$ ls -lrt SYS* -rw-r--r-- 1 grid oinstall 1625300992 Jan 5 16:44 SYSAUX.258 -rw-r--r-- 1 grid oinstall 796925952 Jan 5 16:46 SYSTEM.259
提取其它数据文件的操作与提取system,sysaux数据文件类似，如果能提取到数据库控制文件，system和sysaux系统表空间及其它数据文件，就可以用这些文件来打开数据库。还可能把这个文件“迁移”到别的数据库。需要注意是amdu提取的可能是有损坏或者是已破坏的文件，这取决于文件本身是否有损坏。对于那些由于元信息损坏或者丢失儿导致的不能呗mount的磁盘组，也有可能数据文件是好的，这样情况下同样可以使用amdu来抽取到完好的数据文件。