共享存储：
? das ：direct attached storage 直接附加存储
n IDE
n scsi 磁盘柜 7 15
? nas ： network attached storage网络附加存储 （带有自己的操作系统）
n samba nfs 文件级的共享
n 效率低 带有加锁机制，和推送功能
? san ： 存储区域网络
n fc-san（fiber channer storage area network光纤）fc-switch
u scsi格式 价格昂贵
n ip-san（iscsi：ip）设备为普通设备
u target initiator 认证（ip—账号 --cheap）
n 效率高
群集文件系统 redhat：gfs2 oracle：ocfs2
DRBD：廉价文件同步方案
HA：
Active---standby
Active---active
群集脑裂：split-brain portioned cluster
解决方法： stonith （也叫fence）
硬件：（电源交换机，ssh，meatware）
模块：hp，ibm，sun 机器模块设备
块存储：ext2，ext3（本地文件系统 没有锁机制，没有推送机制）
群集文件系统:有锁机制和推送机制-- redhat：gfs（1-2） oracle：（ocfs2）
iscsi存储管理：
target （tgtd）（服务器）
scsi-target-utils.i386 3260 认证（ip-chanper）
? target id 号码
? 逻辑单元号
iqn格式名字（iqn.日期（年-月）.域名反写.string:substring）
如：iqn.2012-05.com.a.node1:target
管理：tgtadm --lld [driver] --op [operation] --mode [mode] [OPTION]...
--lld [driver] --op new --mode target --tid=[id] --targetname [name]
--lld [driver] --op show --mode target
--lld [driver] --op new --mode=logicalunit --tid=[id] --lun=[lun]
--backing-store [path]
initiator （客户端）
红帽企业存储管理之iscsi简单应用案例：
应用拓扑图：
应用实现步骤：
一．Target-server服务器配置
配置本地yum数据库
[root@target-server ~]# hostname
target-server.junjie.com
[root@target-server ~]# ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:0C:29:1B:F1:BA
inet addr:192.168.101.210 Bcast:192.168.101.255 Mask:255.255.255.0
[root@target-server ~]# vim /etc/yum.repos.d/server.repo
[rhel-server]
name=Red Hat Enterprise Linux server
baseurl=file:///mnt/cdrom/Server/
enabled=1
gpgcheck=1
gpgkey=file:///mnt/cdrom/RPM-GPG-KEY-redhat-release
[rhel-clusterstorage]
name=Red Hat Enterprise Linux clusterstorage
baseurl=file:///mnt/cdrom/ClusterStorage/
enabled=1
gpgcheck=1
gpgkey=file:///mnt/cdrom/RPM-GPG-KEY-redhat-release
[root@target-server ~]# yum list all
安装scsi-target软件包：
[root@target-server ~]# yum list all |grep scsi-target
This system is not registered with RHN.
RHN support will be disabled.
scsi-target-utils.i386 0.0-5.20080917snap.el5
[root@target-server ~]# yum install scsi-target-utils
[root@target-server ~]# rpm -ql scsi-target-utils
/etc/rc.d/init.d/tgtd #服务器控制脚本
/etc/sysconfig/tgtd
/etc/tgt/targets.conf
/usr/sbin/tgt-admin
/usr/sbin/tgt-setup-lun
/usr/sbin/tgtadm #target管理工具
/usr/sbin/tgtd
#设置target开机启动，并启动tgtd服务
[root@target-server ~]# chkconfig tgtd on
[root@target-server ~]# chkconfig --list tgtd
tgtd 0:off 1:off 2:on 3:on 4:on 5:on 6:off
[root@target-server ~]# service tgtd start
Starting SCSI target daemon: [ OK ]
[root@target-server ~]# netstat -tupln |grep tgtd
tcp 0 0 0.0.0.0:3260 0.0.0.0:* LISTEN 3893/tgtd
tcp 0 0 :::3260 :::* LISTEN 3893/tgtd
新建磁盘：（这里使用磁盘分区）
[root@target-server ~]# fdisk -l
Disk /dev/sda: 12.8 GB, 12884901888 bytes
255 heads, 63 sectors/track, 1566 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 1033 8193150 83 Linux
/dev/sda3 1034 1224 1534207+ 82 Linux swap / Solaris
[root@target-server ~]# fdisk /dev/sda
p/n/p//+1000M/p/w
[root@target-server ~]# fdisk -l
Disk /dev/sda: 12.8 GB, 12884901888 bytes
255 heads, 63 sectors/track, 1566 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 1033 8193150 83 Linux
/dev/sda3 1034 1224 1534207+ 82 Linux swap / Solaris
/dev/sda4 1225 1347 987997+ 83 Linux
重新识别分区：（此处不需要格式化挂载）
[root@target-server ~]# cat /proc/partitions
8 0 12582912 sda
8 1 104391 sda1
8 2 8193150 sda2
8 3 1534207 sda3
[root@target-server ~]# partprobe /dev/sda
[root@target-server ~]# cat /proc/partitions
8 0 12582912 sda
8 1 104391 sda1
8 2 8193150 sda2
8 3 1534207 sda3
8 4 987997 sda4
#配置target，新建target设备和逻辑单元设备
[root@target-server ~]# tgtadm --lld iscsi --op new --mode target --tid 1 --targetname iqn.2012-05-22.com.junjie.node1:target
[root@target-server ~]# tgtadm --lld iscsi --op show --mode target
Target 1: iqn.2012-05-22.com.junjie.node1:target
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
Account information:
ACL information:
[root@target-server ~]# tgtadm --lld iscsi --op new --mode logicalunit --tid 1 --lun 1 --backing-store /dev/sda4
[root@target-server ~]# tgtadm --lld iscsi --op show --mode target
Target 1: iqn.2012-05-22.com.junjie.node1:target
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: 1012 MB
Online: Yes
Removable media: No
Backing store: /dev/sda4
Account information:
ACL information:
配置身份验证机制：
[root@target-server ~]# tgtadm --lld iscsi --op bind --mode target --tid 1 --initiator-address 192.168.101.0/24
[root@target-server ~]# tgtadm --lld iscsi --op show --mode target
Target 1: iqn.2012-05-22.com.junjie.node1:target
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: 1012 MB
Online: Yes
Removable media: No
Backing store: /dev/sda4
Account information:
ACL information:
192.168.101.0/24
此时的所有配置为临时配置，开机重启会丢失的，若要永久保持，又如下：2中方法
方法1：将以上脚本写到开机启动脚本中：/etc/rc.d/rc.local
方法2：开机启动
[root@target-server ~]# vim /etc/tgt/targets.conf
二．Initiator-1（存储的客户端）配置
Initiator-1（存储的客户端）
配置本地yum数据库：
[root@initiator-1 ~]# hostname
initiator-1.junjie.com
[root@initiator-1 ~]# ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:0C:29:66:E1:DA
inet addr:192.168.101.211 Bcast:192.168.101.255 Mask:255.255.255.0
[root@initiator-1 ~]# vim /etc/yum.repos.d/server.repo
[rhel-server]
name=Red Hat Enterprise Linux server
baseurl=file:///mnt/cdrom/Server/
enabled=1
gpgcheck=1
gpgkey=file:///mnt/cdrom/RPM-GPG-KEY-redhat-release
[rhel-vt]
name=Red Hat Enterprise Linux vt
baseurl=file:///mnt/cdrom/VT/
enabled=1
gpgcheck=1
gpgkey=file:///mnt/cdrom/RPM-GPG-KEY-redhat-release
[rhel-cluster]
name=Red Hat Enterprise Linux cluster
baseurl=file:///mnt/cdrom/Cluster/
enabled=1
gpgcheck=1
gpgkey=file:///mnt/cdrom/RPM-GPG-KEY-redhat-release
[rhel-clusterstorage]
name=Red Hat Enterprise Linux clusterstorage
baseurl=file:///mnt/cdrom/ClusterStorage/
enabled=1
gpgcheck=1
gpgkey=file:///mnt/cdrom/RPM-GPG-KEY-redhat-release
[root@initiator-1 ~]#
安装配置
[root@initiator-1 ~]# yum install -y iscsi-initiator-utils
[root@initiator-1 ~]# vim /etc/iscsi/initiatorname.iscsi
InitiatorName=iqn.2012-05-22.com.junjie.initiator1
[root@initiator-1 ~]# chkconfig iscsi on
[root@initiator-1 ~]# service iscsi start
iscsid is stopped
Turning off network shutdown. Starting iSCSI daemon: [ OK ]
[ OK ]
Setting up iSCSI targets: iscsiadm: No records found!
[ OK ]
[root@initiator-1 ~]# iscsiadm --mode discovery --type sendtargets --portal 192.168.101.210
192.168.101.210:3260,1 iqn.2012-05-22.com.junjie.node1:target
[root@initiator-1 ~]# iscsiadm --mode node --targetname iqn.2012-05-22.com.junjie.node1:target --portal 192.168.101.210:3260 --login
Logging in to [iface: default, target: iqn.2012-05-22.com.junjie.node1:target, portal: 192.168.101.210,3260]
Login to [iface: default, target: iqn.2012-05-22.com.junjie.node1:target, portal: 192.168.101.210,3260]: successful
[root@initiator-1 ~]# fdisk -l
Disk /dev/sda: 12.8 GB, 12884901888 bytes
255 heads, 63 sectors/track, 1566 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 1033 8193150 83 Linux
/dev/sda3 1034 1224 1534207+ 82 Linux swap / Solaris
Disk /dev/sdb: 1011 MB, 1011709440 bytes
32 heads, 61 sectors/track, 1012 cylinders
Units = cylinders of 1952 * 512 = 999424 bytes
Disk /dev/sdb doesn't contain a valid partition table
此时就相当于本地磁盘（可以随意使用，可以格式化，挂载等）
[root@initiator-1 ~]# fdisk /dev/sdb
p/n/p/1///p/w
[root@initiator-1 ~]# fdisk -l
……
Disk /dev/sdb: 1011 MB, 1011709440 bytes
32 heads, 61 sectors/track, 1012 cylinders
Units = cylinders of 1952 * 512 = 999424 bytes
Device Boot Start End Blocks Id System
/dev/sdb1 1 1012 987681+ 83 Linux
[root@initiator-1 ~]# partprobe /dev/sdb
[root@initiator-1 ~]# mkfs -t ext3 /dev/sdb1
[root@initiator-1 ~]# mkdir /mnt/1
[root@initiator-1 ~]# mount /dev/sdb1 /mnt/1/
[root@initiator-1 ~]# cd /mnt/1/
[root@initiator-1 1]# mkdir d1 d2 d3
[root@initiator-1 1]# touch f1 f2 f3
[root@initiator-1 1]# ll
total 28
drwxr-xr-x 2 root root 4096 Apr 1 11:37 d1
drwxr-xr-x 2 root root 4096 Apr 1 11:37 d2
drwxr-xr-x 2 root root 4096 Apr 1 11:37 d3
-rw-r--r-- 1 root root 0 Apr 1 11:37 f1
-rw-r--r-- 1 root root 0 Apr 1 11:37 f2
-rw-r--r-- 1 root root 0 Apr 1 11:37 f3
drwx------ 2 root root 16384 Apr 1 11:34 lost+found
三．Initiator-2（存储的客户端）配置
Initiator-2（存储的客户端）
配置本地yum数据库：
[root@initiator-2~]# hostname
initiator-2.junjie.com
[root@initiator-2 ~]# ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:0C:29:79:F8:F7
inet addr:192.168.101.212 Bcast:192.168.101.255 Mask:255.255.255.0
[root@initiator-2 ~]# vim /etc/yum.repos.d/server.repo
[rhel-server]
name=Red Hat Enterprise Linux server
baseurl=file:///mnt/cdrom/Server/
enabled=1
gpgcheck=1
gpgkey=file:///mnt/cdrom/RPM-GPG-KEY-redhat-release
[rhel-vt]
name=Red Hat Enterprise Linux vt
baseurl=file:///mnt/cdrom/VT/
enabled=1
gpgcheck=1
gpgkey=file:///mnt/cdrom/RPM-GPG-KEY-redhat-release
[rhel-cluster]
name=Red Hat Enterprise Linux cluster
baseurl=file:///mnt/cdrom/Cluster/
enabled=1
gpgcheck=1
gpgkey=file:///mnt/cdrom/RPM-GPG-KEY-redhat-release
[rhel-clusterstorage]
name=Red Hat Enterprise Linux clusterstorage
baseurl=file:///mnt/cdrom/ClusterStorage/
enabled=1
gpgcheck=1
gpgkey=file:///mnt/cdrom/RPM-GPG-KEY-redhat-release
[root@initiator-2 ~]#
安装配置
[root@initiator-2 ~]# yum install -y iscsi-initiator-utils
[root@initiator-2 ~]# vim /etc/iscsi/initiatorname.iscsi
InitiatorName=iqn.2012-05-22.com.junjie.initiator2
[root@initiator-2 ~]# service iscsi start
iscsid is stopped
Turning off network shutdown. Starting iSCSI daemon: [ OK ]
[ OK ]
Setting up iSCSI targets: iscsiadm: No records found!
[ OK ]
[root@initiator-2 ~]# iscsiadm --mode discovery --type sendtargets --portal 192.168.101.210
192.168.101.210:3260,1 iqn.2012-05-22.com.junjie.node1:target
[root@initiator-2 ~]# iscsiadm --mode node --targetname iqn.2012-05-22.com.junjie.node1:target --portal 192.168.101.210:3260 --login
Logging in to [iface: default, target: iqn.2012-05-22.com.junjie.node1:target, portal: 192.168.101.210,3260]
Login to [iface: default, target: iqn.2012-05-22.com.junjie.node1:target, portal: 192.168.101.210,3260]: successful
[root@initiator-2 ~]# fdisk -l
………….
Disk /dev/sdb: 1011 MB, 1011709440 bytes
32 heads, 61 sectors/track, 1012 cylinders
Units = cylinders of 1952 * 512 = 999424 bytes
Device Boot Start End Blocks Id System
/dev/sdb1 1 1012 987681+ 83 Linux
[root@initiator-2 ~]#
此时就相当于本地磁盘（可以随意使用，可以格式化，挂载等）
[root@initiator-2 ~]# mkdir /mnt/1
[root@initiator-2 ~]# mount /dev/sdb1 /mnt/1/
[root@initiator-2 ~]# cd /mnt/1/
[root@initiator-2 1]# ll
total 28
drwxr-xr-x 2 root root 4096 Apr 1 11:37 d1
drwxr-xr-x 2 root root 4096 Apr 1 11:37 d2
drwxr-xr-x 2 root root 4096 Apr 1 11:37 d3
-rw-r--r-- 1 root root 0 Apr 1 11:37 f1
-rw-r--r-- 1 root root 0 Apr 1 11:37 f2
-rw-r--r-- 1 root root 0 Apr 1 11:37 f3
drwx------ 2 root root 16384 Apr 1 11:34 lost+found
（发现存储设备上的文件信息应经存在）
四．测试文件的锁机制和推送机制
由于该文件系统是块存储：ext2，ext3本地文件系统，故没有锁机制，也没有推送机制
4.1测试推送功能
在initiator-2上创建qq文件
[root@initiator-2 1]# echo "01" >f1
[root@initiator-2 1]# touch qq
[root@initiator-2 1]# ll
total 32
drwxr-xr-x 2 root root 4096 Apr 1 11:37 d1
drwxr-xr-x 2 root root 4096 Apr 1 11:37 d2
drwxr-xr-x 2 root root 4096 Apr 1 11:37 d3
-rw-r--r-- 1 root root 3 Apr 1 12:03 f1
-rw-r--r-- 1 root root 0 Apr 1 11:37 f2
-rw-r--r-- 1 root root 0 Apr 1 11:37 f3
drwx------ 2 root root 16384 Apr 1 11:34 lost+found
-rw-r--r-- 1 root root 0 Apr 1 12:03 qq
在initiator-1上没有发现qq文件
[root@initiator-1 1]# ll
total 28
drwxr-xr-x 2 root root 4096 Apr 1 11:37 d1
drwxr-xr-x 2 root root 4096 Apr 1 11:37 d2
drwxr-xr-x 2 root root 4096 Apr 1 11:37 d3
-rw-r--r-- 1 root root 0 Apr 1 11:37 f1
-rw-r--r-- 1 root root 0 Apr 1 11:37 f2
-rw-r--r-- 1 root root 0 Apr 1 11:37 f3
drwx------ 2 root root 16384 Apr 1 11:34 lost+found
[root@initiator-1 1]#
4.2测试锁机制功能
经过测试可以知道：块存储：ext2，ext3本地文件系统，故没有锁机制，也没有推送机制
附录：
initiator卸载远端存储设备：
iscsiadm --mode node -T iqn.2011-09-28:disk1 -p 192.168.0.254:3260 --logout(在service iscsi restart后又会注册)
iscsiadm --mode node -T iqn.2011-09-28:disk1 -p 192.168.0.254:3260 -o delete
转载自