RHCE7认证学习笔记34——配置ISCSI

一、存储设备类型

• DSA：直接区域存储
• NAS:网络区域存储
• SAN：存储区域网络，块级别共享

二、配置iscsi服务器端

这里举例子说明，假如服务器有2个分区/dev/sdb7,/dev/sdb8要共享出去:    
    /dev/sdb7      1230848      1640447    200M  Linux filesyste 
    /dev/sdb8      1640448      2459647    400M  Linux filesyste

安装target包：
[root@it.net.cn ~]# yum install target\* -y

启动target服务
[root@it.net.cn ~]# systemctl start target 
    
配置步骤：

1、准备要共享的块；

使用targetcli命令进入target配置界面：
 [root@it.net.cn ~]# targetcli

/> pwd
/ 
/> ls
o- / ......................................................................................................................... [...] 
  o- backstores .............................................................................................................. [...] 
  | o- block .................................................................................................. [Storage Objects: 0] 
  | o- fileio ................................................................................................. [Storage Objects: 0] 
  | o- pscsi .................................................................................................. [Storage Objects: 0] 
  | o- ramdisk ................................................................................................ [Storage Objects: 0] 
  o- iscsi ............................................................................................................ [Targets: 0] 
  o- loopback ......................................................................................................... [Targets: 0]

进入backstores/block目录创建要共享的块，创建block1和block2：
        
/> cd backstores/ 
/backstores> ls
o- backstores ................................................................................................................ [...] 
  o- block .................................................................................................... [Storage Objects: 0] 
  o- fileio ................................................................................................... [Storage Objects: 0] 
  o- pscsi .................................................................................................... [Storage Objects: 0] 
  o- ramdisk .................................................................................................. [Storage Objects: 0] 
        
/backstores/block> create block1 dev=/dev/sdb7
Created block storage object block1 using /dev/sdb7. 
/backstores/block> create block2 dev=/dev/sdb8
Created block storage object block2 using /dev/sdb8.

/backstores/block> ls
o- block ...................................................................................................... [Storage Objects: 2] 
  o- block1 .......................................................................... [/dev/sdb7 (200.0MiB) write-thru deactivated] 
  o- block2 .......................................................................... [/dev/sdb8 (400.0MiB) write-thru deactivated]

exit退出保存targetcli，并重新进入：
/backstores/block> exit
Global pref auto_save_on_exit=true
Last 10 configs saved in /etc/target/backup. 
Configuration saved to /etc/target/saveconfig.json 
[root@it.net.cn ~]# targetcli

2、创建一个target;

target标准名字格式：

年  月  域名倒写 名字

iqn.2015-02.com.sg:disk1

进入iscsi目录，创建target:

/iscsi> create iqn.2015-02.com.sg:disk1 
                    
/iscsi> ls
o- iscsi .............................................................................................................. [Targets: 1] 
  o- iqn.2015-02.com.sg:disk1 ............................................................................................ [TPGs: 1]

3、在target上面创建一个lun；

进入/iscsi/iqn.2015-02.com.sg:disk1/tpg1目录：      
 /iscsi/iqn.20...sg:disk1/tpg1> ls
o- tpg1 ..................................................................................................... [no-gen-acls, no-auth] 
  o- acls ................................................................................................................ [ACLs: 0] 
  o- luns ................................................................................................................ [LUNs: 0] 
  o- portals .......................................................................................................... [Portals: 0]

acls目录创建共享密码：                    
 /iscsi/iqn.20...sg:disk1/tpg1> acls/ create iqn.2015-02.com.sg:diskpasswd

创建lun:        
/iscsi/iqn.20...sg:disk1/tpg1> luns/ create /backstores/block/block1
Created LUN 0. 
Created LUN 0->0 mapping in node ACL iqn.2015-02.com.sg:diskpasswd 
/iscsi/iqn.20...sg:disk1/tpg1> luns/ create /backstores/block/block2
Created LUN 1. 
Created LUN 1->1 mapping in node ACL iqn.2015-02.com.sg:diskpasswd

 o- luns .......................................................................................................... [LUNs: 2] 
  |    | o- lun0 ....................................................................................... [block/block1 (/dev/sdb7)] 
  |    | o- lun1 ....................................................................................... [block/block2 (/dev/sdb8)]

portal创建共享端口和地址：
/iscsi/iqn.20...sg:disk1/tpg1> portals/ create 10.35.89.32 
Using default IP port 3260 
Created network portal 10.35.89.32:3260.

exit退出并保存：

Configuration saved to /etc/target/saveconfig.json

配置文件保存在：/etc/target/saveconfig.json，可以直接修改配置文件

三、客户端配置iscsi连接

安装target包：  
[root@client ~]# yum install target\* -y

查看fuw服务器端共享的内容：
[root@client ~]# iscsiadm -m discovery -t st -p 10.35.89.32 
10.35.89.32:3260,1 iqn.2015-02.com.sg:disk1

编辑/etc/iscsi/initiatorname.iscsi文件，配置服务器端共享的名字和密码：
InitiatorName=iqn.2015-02.com.sg:diskpasswd

重启iscscid服务：

[root@client ~]# systemctl restart iscsid.service

挂载服务器端共享的内容：

[root@client ~]# iscsiadm -m node -T iqn.2015-02.com.sg:disk1 -p 10.35.89.32 -l

挂载成功后，使用fdisk命令即可查看到新增加的两块磁盘：

断开挂载的连接：
[root@client ~]# iscsiadm -m node -T iqn.2015-02.com.sg:disk1 -p 10.35.89.32 -u

使用fdisk命令划分共享的磁盘，格式化，并挂载文件夹，编辑fstab文件设置开机自动挂载：
 [root@client ~]# fdisk /dev/sdb

Device Boot      Start        End      Blocks  Id  System 
/dev/sdb1            8192      114687      53248  83  Linux

[root@client ~]# mkfs.xfs /dev/sdb1

[root@client /]# mount /dev/sdb1 /aa

编辑fstab文件时候，将default换成_netdev参数：

/dev/sdb1      /aa    xfs    _netdev 0 0