環境：
* Dell R710 E5520*2/146GB*6 SAS/2GB*4
* Integrated RAID Controller（HW）
* CentOS 5.x
一開始要先找到系統上的 RAID Controller 系統型號是什麼，試了以下的方式。
root@m001 { /proc/scsi }$ cat scsi
Attached devices:
Host: scsi0 Channel: 02 Id: 00 Lun: 00
Vendor: DELL Model: PERC H700 Rev: 2.0.
Type: Direct-Access ANSI SCSI revision: 05
Host: scsi1 Channel: 00 Id: 00 Lun: 00
Vendor: PLDS Model: DVD+-RW DS-8A3S Rev: HD52
Type: CD-ROM ANSI SCSI revision: 05
不過，我的系統是用 SAS 的，所以應該不是這一個。再試
root@m001 { /proc }$ cat devices
Character devices:
1 mem
4 /dev/vc/0
4 tty
4 ttyS
5 /dev/tty
5 /dev/console
5 /dev/ptmx
6 lp
7 vcs
10 misc
13 input
21 sg
29 fb
128 ptm
136 pts
162 raw
180 usb
189 usb_device
202 cpu/msr
203 cpu/cpuid
216 rfcomm
251 blktap
252 uio
253 megaraid_sas_ioctl
254 pcmcia
Block devices:
1 ramdisk
8 sd
9 md
11 sr
65 sd
66 sd
67 sd
68 sd
69 sd
70 sd
71 sd
128 sd
129 sd
130 sd
131 sd
132 sd
133 sd
134 sd
135 sd
253 device-mapper
254 mdp
也沒看出什麼端泥
root@m001 { /proc }$ cat diskstats
1 0 ram0 0 0 0 0 0 0 0 0 0 0 0
1 1 ram1 0 0 0 0 0 0 0 0 0 0 0
1 2 ram2 0 0 0 0 0 0 0 0 0 0 0
1 3 ram3 0 0 0 0 0 0 0 0 0 0 0
1 4 ram4 0 0 0 0 0 0 0 0 0 0 0
1 5 ram5 0 0 0 0 0 0 0 0 0 0 0
1 6 ram6 0 0 0 0 0 0 0 0 0 0 0
1 7 ram7 0 0 0 0 0 0 0 0 0 0 0
1 8 ram8 0 0 0 0 0 0 0 0 0 0 0
1 9 ram9 0 0 0 0 0 0 0 0 0 0 0
1 10 ram10 0 0 0 0 0 0 0 0 0 0 0
1 11 ram11 0 0 0 0 0 0 0 0 0 0 0
1 12 ram12 0 0 0 0 0 0 0 0 0 0 0
1 13 ram13 0 0 0 0 0 0 0 0 0 0 0
1 14 ram14 0 0 0 0 0 0 0 0 0 0 0
1 15 ram15 0 0 0 0 0 0 0 0 0 0 0
8 0 sda 2912902 5836954 68738123 7169600 160459782 17123814 1395096183 25929156 0 13643852 33091376
8 1 sda1 40 239 580 256 0 0 0 0 0 224 256
8 2 sda2 119 381 638 256 0 0 0 0 0 228 256
8 3 sda3 98 1738 2073 300 26 10 70 16 0 268 316
8 4 sda4 4 0 8 48 0 0 0 0 0 48 48
8 5 sda5 2912623 5834579 68734544 7168636 160459756 17123804 1395096113 25929140 0 13643356 33089664
253 0 dm-0 9539 0 268418 38228 2335167 0 18681336 3292088 0 1955100 3331236
253 1 dm-1 8687278 0 67271513 17692256 154407246 0 1209683729 24606260 0 8434120 42334020
253 2 dm-2 12322 0 263170 11840 16610092 0 132880736 14888900 0 4044548 14900772
253 3 dm-3 284 0 2266 952 2883732 0 23069856 468160 0 61080 469112
253 4 dm-4 39746 0 928154 173252 1347557 0 10780456 917888 0 69840 1091140
253 5 dm-5 75 0 600 304 0 0 0 0 0 52 304
11 0 sr0 7 10 136 3248 0 0 0 0 0 3144 3248
9 0 md0 0 0 0 0 0 0 0 0 0 0 0
有看到 sdx ,不過沒什麼用
root@m001 { /proc }$ dmidecode | grep -i sas
root@m001 { /proc }$ dmidecode | less
root@m001 { /proc }$ dmidecode
# dmidecode 2.7
SMBIOS 2.6 present.
83 structures occupying 4569 bytes.
Table at 0xCF79C000.
Handle 0xDA00, DMI type 218, 11 bytes.
OEM-specific Type
Header and Data:
DA 0B 00 DA B2 00 17 00 0E 20 00
Handle 0x0000, DMI type 0, 24 bytes.
BIOS Information
Vendor: Dell Inc.
Version: 1.3.6
Release Date: 10/30/2009
Address: 0xF0000
Runtime Size: 64 kB
ROM Size: 4096 kB
......
連這個都沒有。最後試到
root@m001 { /proc }$ dmesg | grep -i sas
megasas: 00.00.04.31-RH1 Tues. June. 15 14:13:02 EST 2010
megasas: 0x1000:0x0079:0x1028:0x1f17: bus 3:slot 0:func 0
gen2: instance->base_addr = df1bc000<6>megasas: FW now in Ready state
megasas_init_mfi: fw_support_ieee=0<6>scsi0 : LSI SAS based MegaRAID driver
終於有了。不過，怎麼不是它 SPEC 上說的 PERC 6/xx , SAS 5/E 呢？
不過，這個 MegaRAID driver 到是很多人討論到，所以就跟著找下去了。然後，找到了 LSI MegaRaid – MegaCli Linux Commands 這篇，就照著它，去 LSI Web Site 下載它的命令列工具。我是用第二頁的 MegaRAID SAS MegaCLI - Linux, Version 1.01.39 這個檔案。把 rpm 裝一下唄
[root@qa1 ~]# rpm -Uvh MegaCli-1.01.39-0.i386.rpm [root@qa1 ~]# rpm -ql MegaCli-1.01.39-0 /opt/MegaRAID/MegaCli/MegaCli /opt/MegaRAID/MegaCli/MegaCli64
接著去看看 help 吧. 一堆 command（請小心使用，它可以直接修改，刪除 VD）。由於我只要查詢而已，所以就執行以下 command.
[root@qa1 ~]# /opt/MegaRAID/MegaCli/MegaCli64 -AdpAllInfo -aAll
Adapter #0
==============================================================================
Versions
================
Product Name : PERC 6/i Integrated
Serial No : 1122334455667788
FW Package Build: 6.2.0-0013
Mfg. Data
================
Mfg. Date : 06/24/08
Rework Date : 06/24/08
......
終於看到它是：PERC 6/i Integrated, 然後
[root@qa1 ~]# /opt/MegaRAID/MegaCli/MegaCli64 -LDInfo -L0 -a0
Adapter 0 -- Virtual Drive Information:
Virtual Disk: 0 (target id: 0)
Name:
RAID Level: Primary-5, Secondary-0, RAID Level Qualifier-3
Size:696960MB
State: Optimal
Stripe Size: 64kB
Number Of Drives:6
Span Depth:1
Default Cache Policy: WriteBack, ReadAheadNone, Direct, No Write Cache if Bad BBU
Current Cache Policy: WriteBack, ReadAheadNone, Direct, No Write Cache if Bad BBU
Access Policy: Read/Write
Disk Cache Policy: Disk's Default
噔噔！終於出現了。原來是 RAID 5.
