Centos7配置iscsi多路径

主机是kvm宿主机，安装了虚拟化组件

编辑/etc/iscsi/iscsid.conf 

[root@192 ~]# vi /etc/iscsi/iscsid.conf 

node.session.auth.authmethod = CHAP

node.session.auth.username = admin
node.session.auth.password = 123456789123

discovery.sendtargets.auth.authmethod = CHAP

discovery.sendtargets.auth.username = admin
discovery.sendtargets.auth.password = 123456789123

[root@192 ~]# systemctl restart iscsid

[root@192 ~]# iscsiadm -m discovery -t st -p 192.168.0.20
iscsiadm: No portals found                        \\iscsi服务器上未添加权限，所以这里要先去服务器上添加本机的权限

[root@192 ~]# cat /etc/iscsi/initiatorname.iscsi 
InitiatorName=iqn.1994-05.com.redhat:335c72a789d    \\把iqn添加到服务器

添加完成后重新扫描

[root@192 ~]# iscsiadm -m discovery -t st -p 192.168.0.20
192.168.0.20:3260,1 iqn.1991-05.com.microsoft:win-8olmgmomodt-192.168.10.5-target
192.168.20.20:3260,1 iqn.1991-05.com.microsoft:win-8olmgmomodt-192.168.10.5-target

挂载

[root@192 ~]# iscsiadm -m node -p 192.168.0.20 -l
Logging in to [iface: default, target: iqn.1991-05.com.microsoft:win-8olmgmomodt-192.168.10.5-target, portal: 192.168.0.20,3260] (multiple)
Login to [iface: default, target: iqn.1991-05.com.microsoft:win-8olmgmomodt-192.168.10.5-target, portal: 192.168.0.20,3260] successful.

[root@192 ~]# iscsiadm -m node -p 192.168.20.20 -l
Logging in to [iface: default, target: iqn.1991-05.com.microsoft:win-8olmgmomodt-192.168.10.5-target, portal: 192.168.20.20,3260] (multiple)
Login to [iface: default, target: iqn.1991-05.com.microsoft:win-8olmgmomodt-192.168.10.5-target, portal: 192.168.20.20,3260] successful.

运行fdisk查看

Disk /dev/sdb: 96.6 GB, 96636764160 bytes, 188743680 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes




Disk /dev/sdc: 96.6 GB, 96636764160 bytes, 188743680 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

已经发现两块新硬盘

安装多路径软件

[root@192 ~]# yum install device-mapper-multipath -y

加载多路径模块

[root@192 ~]# modprobe dm-multipath
[root@192 ~]# modprobe dm-round-robin
[root@192 ~]# modprobe dm-service-time

启动服务

[root@192 ~]# systemctl start multipathd.service 
[root@192 ~]# multipath -ll
Dec 19 15:09:30 | /etc/multipath.conf does not exist, blacklisting all devices.
Dec 19 15:09:30 | A default multipath.conf file is located at
Dec 19 15:09:30 | /usr/share/doc/device-mapper-multipath-0.4.9/multipath.conf
Dec 19 15:09:30 | You can run /sbin/mpathconf to create or modify /etc/multipath.conf
[root@192 ~]# systemctl status multipathd.service 
● multipathd.service - Device-Mapper Multipath Device Controller
   Loaded: loaded (/usr/lib/systemd/system/multipathd.service; enabled; vendor preset: enabled)
   Active: inactive (dead)
Condition: start condition failed at Sat 2015-12-19 15:09:08 CST; 41s ago
           ConditionPathExists=/etc/multipath.conf was not met


Dec 19 15:09:08 192.168.0.119 systemd[1]: Started Device-Mapper Multipath Device Controller.

发现服务没起来，原因是没有配置文件，按照上面的提示拷贝一份过去

[root@192 ~]# cp /usr/share/doc/device-mapper-multipath-0.4.9/multipath.conf /etc/multipath.conf

[root@192 ~]# systemctl start multipathd.service 
[root@192 ~]# multipath -ll
mpatha (360003ff44dc75adc9d7f6d4a54e065f8) dm-4 MSFT    ,Virtual HD      
size=90G features='0' hwhandler='0' wp=rw
|-+- policy='service-time 0' prio=1 status=active
| `- 3:0:0:0 sdb 8:16 active ready running
`-+- policy='service-time 0' prio=1 status=enabled
  `- 4:0:0:0 sdc 8:32 active ready running

已经看到了，然后编辑 /etc/multipath.conf，把设备重命名一下

加入如下内容

multipaths {
        multipath {
                wwid                    360003ff44dc75adc9d7f6d4a54e065f8
                alias                   kvm
        }
 }
blacklist {
devnode "sda"
}

重启服务

[root@192 ~]# systemctl restart multipathd.service 
[root@192 ~]# multipath -ll
kvm (360003ff44dc75adc9d7f6d4a54e065f8) dm-4 MSFT    ,Virtual HD      
size=90G features='0' hwhandler='0' wp=rw
|-+- policy='service-time 0' prio=1 status=active
| `- 3:0:0:0 sdb 8:16 active ready running
`-+- policy='service-time 0' prio=1 status=enabled
  `- 4:0:0:0 sdc 8:32 active ready running

运行fdisk查看就可以看到这样一块设备了

Disk /dev/mapper/kvm: 96.6 GB, 96636764160 bytes, 188743680 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

如果此设备是第一次被挂载，需要如下操作

pvcreate  /dev/mapper/kvm          创建物理卷

mkfs.ext4  /dev/mapper/kvm        格式化

如果是多台机器共享此设备，第二台就无需以上操作了，直接挂载即可

mount  /dev/mapper/kvm   /mnt/iscsi

开机自动加载

[root@192 ~]# vi /etc/fstab 

/dev/mapper/kvm         /mnt/iscsi              ext4    _netdev          0 0

[root@192 ~]# mount -a
[root@192 ~]# df -TH
Filesystem                  Type      Size  Used Avail Use% Mounted on
/dev/mapper/centos_192-root xfs        11G  1.5G  9.3G  14% /
devtmpfs                    devtmpfs  4.2G     0  4.2G   0% /dev
tmpfs                       tmpfs     4.2G     0  4.2G   0% /dev/shm
tmpfs                       tmpfs     4.2G  9.1M  4.2G   1% /run
tmpfs                       tmpfs     4.2G     0  4.2G   0% /sys/fs/cgroup
/dev/mapper/centos_192-home xfs       5.4G   34M  5.4G   1% /home
/dev/mapper/centos_192-data xfs        83G   34M   83G   1% /data
/dev/sda1                   xfs       521M  140M  381M  27% /boot
tmpfs                       tmpfs     836M     0  836M   0% /run/user/0
/dev/mapper/kvm             ext4       95G   16G   75G  17% /mnt/iscsi

重启验证