Linux ISCSI服务配置

Linux ISCSI服务配置，客户端进行访问

环境配置:

• server端 172.25.0.11
• client端 172.25.0.10

配置ISCSI服务端

1、安装软件包

yum install targetcli -y

2、防火墙放行target的端口 3260

[root@server0 ~]# firewall-cmd --permanent --add-port=3260/tcp
success
[root@server0 ~]# firewall-cmd --reload
success
[root@server0 ~]# firewall-cmd --list-all
public (default, active)
interfaces: eth0
sources: 
services: dhcpv6-client ssh
ports: 3260/tcp
masquerade: no
forward-ports: 
icmp-blocks: 
rich rules:

3、准备本地块设备，也就是准备磁盘

[root@server0 ~]# fdisk /dev/sdb 
Command (m for help): n
Partition type:
p primary (0 primary, 0 extended, 4 free)
e extended
Select (default p): p
Partition number (1-4, default 1): 回车
First sector (2048-20971519, default 2048): 回车
Last sector, +sectors or +size{K,M,G} (2048-20971519, default 20971519): 回车

Command (m for help): p p查看刚刚分好的新区
Disk identifier: 0x6dc8b66f

Device Boot Start End Blocks Id System
/dev/sdb1 2048 20971519 10484736 83 Linux

Command (m for help): w 保存
[root@server0 ~]# partprobe 
[root@server0 ~]# lsblk 可以看见系统已经生成sdb1的设备文件
...
sdb 8:16 0 10G 0 disk 
└─sdb1 8:17 0 10G 0 part

创建逻辑卷

[root@server0 ~]# pvcreate /dev/sdb1 ---->创物理卷
Physical volume "/dev/sdb1" successfully created
[root@server0 ~]# pvs
PV VG Fmt Attr PSize PFree 
/dev/sdb1 lvm2 a-- 10.00g 10.00g

[root@server0 ~]# vgcreate ISCSI_vg /dev/sdb1	---->创建名为ISCSI_vg卷组
Volume group "ISCSI_vg" successfully created
[root@server0 ~]# vgs
VG #PV #LV #SN Attr VSize VFree 
ISCSI_vg 1 0 0 wz--n- 10.00g 10.00g

[root@server0 ~]# lvcreate -n disk1_lv -L 100m ISCSI_vg	---->创建名为disk1_lv的逻辑卷
Logical volume "disk1_lv" created
[root@server0 ~]# lvs
LV VG Attr LSize Pool Origin Data% Move Log Cpy%Sync Convert
disk1_lv ISCSI_vg -wi-a----- 100.00m 

4、创建target，本节重点，也是最不容易理解的地方

首先打开targetcli工具，ls可以看见目前target下没有任何配置

[root@server0 ~]# targetcli 
/> 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]
/> 

(1)创建名为 iqn.2014-06.com.example.com:server0的target

/> /iscsi create iqn.2014-06.com.example.com:server0
Created target iqn.2014-06.com.example.com:server0.
Created TPG 1 
可以看到iscsi创建了一个名为iqn.2014-06.com.example.com:server0的target，并且系统又在底下自动创建了tgp1
/> ls
o- iscsi ................................................................................................ [Targets: 1]
| o- iqn.2014-06.com.example.com:server0 ................................................................... [TPGs: 1]
| o- tpg1 ................................................................................... [no-gen-acls, no-auth]
| o- acls .............................................................................................. [ACLs: 0]
| o- luns .............................................................................................. [LUNs: 0]
| o- portals ........................................................................................ [Portals: 0]
o- loopback ............................................................................................. [Targets: 0
/> 

(2)为tgp1定义portals，也就是定义ip和端口

/> /iscsi/iqn.2014-06.com.example.com:server0/tpg1/portals create 172.25.0.11 3260
Using default IP port 3260
Created network portal 172.25.0.11:3260.
/> ls
| o- iqn.2014-06.com.example.com:server0 ................................................................... [TPGs: 1]
| o- tpg1 ................................................................................... [no-gen-acls, no-auth]
| o- acls .............................................................................................. [ACLs: 0]
| o- luns .............................................................................................. [LUNs: 0]
| o- portals ........................................................................................ [Portals: 1]
| o- 172.25.0.11:3260 ..................................................................................... [OK]
o- loopback ............................................................................................. [Targets: 0]

(3)为target绑定本地块设备，绑定刚刚创建的逻辑卷 

首先定义一个block

/> /backstores/block create name=server0.disk1 dev=/dev/ISCSI_vg/disk1_lv 
Created block storage object server0.disk1 using /dev/ISCSI_vg/disk1_lv
/> ls
o- / ............................................................................................................. [...]
o- backstores .................................................................................................. [...]
| o- block ...................................................................................... [Storage Objects: 1]
| | o- server0.disk1 ...................................... [/dev/ISCSI_vg/disk1_lv (100.0MiB) write-thru deactivated

为target指定LUN（逻辑单元号）,也就是把刚才定义的block分配给target

/> /iscsi/iqn.2014-06.com.example.com:server0/tpg1/luns create /backstores/block/server0.disk1 
Created LUN 0.
/> ls
o- iscsi ................................................................................................ [Targets: 1]
| o- iqn.2014-06.com.example.com:server0 ................................................................... [TPGs: 1]
| o- tpg1 ................................................................................... [no-gen-acls, no-auth]
| o- acls .............................................................................................. [ACLs: 0]
| o- luns .............................................................................................. [LUNs: 1]
| | o- lun0 ....................................................... [block/server0.disk1 (/dev/ISCSI_vg/disk1_lv)]
| o- portals ........................................................................................ [Portals: 1]
| o- 172.25.0.11:3260 ..................................................................................... [OK]
o- loopback ............................................................................................. [Targets: 0

(4)为target设定acl(访问控制列表)

配置只允许名为 iqn.2014-06.com.example:desktop0的客户端访问

/> iscsi/iqn.2014-06.com.example.com:server0/tpg1/acls create iqn.2014-06.com.example:desktop0
Created Node ACL for iqn.2014-06.com.example:desktop0
Created mapped LUN 0.

关闭密码验证

/> /iscsi/iqn.2014-06.com.example.com:server0/tpg1/ set attribute authentication=0
Parameter authentication is now '0'.

关闭tgp级别的acl节点限制,也就是只针对tgp/acl下的initiator进行限制，而不是整个tgp

/> /iscsi/iqn.2014-06.com.example.com:server0/tpg1/ set attribute generate_node_acls=0
Parameter generate_node_acls is now '0'.

(5)保存退出

/> saveconfig 配置完毕保存
/> exit	退出

最后配置下来总的列表就是这样

/> ls
o- / ............................................................................................................. [...]
o- backstores .................................................................................................. [...]
| o- block ...................................................................................... [Storage Objects: 1]
| | o- server0.disk1 ........................................ [/dev/ISCSI_vg/disk1_lv (100.0MiB) write-thru activated]
| o- fileio ..................................................................................... [Storage Objects: 0]
| o- pscsi ...................................................................................... [Storage Objects: 0]
| o- ramdisk .................................................................................... [Storage Objects: 0]
o- iscsi ................................................................................................ [Targets: 1]
| o- iqn.2014-06.com.example.com:server0 ................................................................... [TPGs: 1]
| o- tpg1 ................................................................................... [no-gen-acls, no-auth]
| o- acls .............................................................................................. [ACLs: 1]
| | o- iqn.2014-06.com.example:desktop0 ......................................................... [Mapped LUNs: 1]
| | o- mapped_lun0 ............................................................. [lun0 block/server0.disk1 (rw)]
| o- luns .............................................................................................. [LUNs: 1]
| | o- lun0 ....................................................... [block/server0.disk1 (/dev/ISCSI_vg/disk1_lv)]
| o- portals ........................................................................................ [Portals: 1]
| o- 172.25.0.11:3260 ..................................................................................... [OK]
o- loopback ............................................................................................. [Targets: 0

服务端配置完成
错误补救:
万一有写错了配置，就删掉重新进行配置，可以看见portals已经没有内容了

/> /iscsi/iqn.2014-06.com.example.com:server0/tpg1/portals/ delete 172.25.0.11 3260
Deleted network portal 172.25.0.11:3260
/> ls
o- iscsi ................................................................................................ [Targets: 1]
| o- iqn.2014-06.com.example.com:server0 ................................................................... [TPGs: 1]
| o- tpg1 ................................................................................... [no-gen-acls, no-auth]
| o- acls .............................................................................................. [ACLs: 1]
| | o- iqn.2014-06.com.example:desktop0 ......................................................... [Mapped LUNs: 1]
| | o- mapped_lun0 ............................................................. [lun0 block/server0.disk1 (rw)]
| o- luns .............................................................................................. [LUNs: 1]
| | o- lun0 ....................................................... [block/server0.disk1 (/dev/ISCSI_vg/disk1_lv)]
| o- portals ........................................................................................ [Portals: 0]
o- loopback ............................................................................................. [Targets: 0]

重新配置

/> /iscsi/iqn.2014-06.com.example.com:server0/tpg1/portals create 172.25.0.11 3260
Using default IP port 3260
Created network portal 172.25.0.11:3260.
/> ls
| o- iqn.2014-06.com.example.com:server0 ................................................................... [TPGs: 1]
| o- tpg1 ................................................................................... [no-gen-acls, no-auth]
| o- acls .............................................................................................. [ACLs: 1]
| | o- iqn.2014-06.com.example:desktop0 ......................................................... [Mapped LUNs: 1]
| | o- mapped_lun0 ............................................................. [lun0 block/server0.disk1 (rw)]
| o- luns .............................................................................................. [LUNs: 1]
| | o- lun0 ....................................................... [block/server0.disk1 (/dev/ISCSI_vg/disk1_lv)]
| o- portals ........................................................................................ [Portals: 1]
| o- 172.25.0.11:3260 ..................................................................................... [OK]
o- loopback ............................................................................................. [Targets: 0

client端配置

1、安装软件包

[root@desktop0 ~]# yum install iscsi-initiator-utils -y 红帽系统一般都会安装，所以此步骤可以跳过

2、启动服务，并设定开机重启

[root@desktop0 ~]# systemctl start iscsi iscsid
[root@desktop0 ~]# systemctl enable iscsi iscsid

3、修改文件，因为服务端中acls指定只允许名为iqn.2014-06.com.example:dekstop0的设备去访问，所以这个文件就这样配置

[root@desktop0 ~]# vim /etc/iscsi/initiatorname.iscsi 
InitiatorName=iqn.2014-06.com.example:desktop0
修改之后重启iscisd服务
[root@desktop0 ~]# systemctl restart iscsid

4、发现设备

[root@desktop0 ~]# iscsiadm -m discovery -t st -p 172.25.0.11 
172.25.0.11:3260,1 iqn.2014-06.com.example.com:server0

5、登录iscsi 

首先查看一下目前系统设备

[root@desktop0 ~]# lsblk 
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 10G 0 disk 
└─sda1 8:1 0 10G 0 part /
sdb 8:16 0 10G 0 disk 
sr0 11:0 1 1024M 0 rom 

登录

[root@desktop0 ~]# iscsiadm -m node -T iqn.2014-06.com.example.com:server0 -l
或者可以写为
[root@desktop0 ~]# iscsiadm -m node -l

可以发现多了一块100M的磁盘

[root@desktop0 ~]# lsblk 
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 10G 0 disk 
└─sda1 8:1 0 10G 0 part /
sdb 8:16 0 10G 0 disk 
sdc 8:32 0 100M 0 disk 
sr0 11:0 1 1024M 0 rom 

6、对磁盘进行分区

分区

[root@desktop0 ~]# fdisk /dev/sdc 
Command (m for help): n
Select (default p): p
Partition number (1-4, default 1): 回车
First sector (8192-204799, default 8192): 回车
Using default value 8192
Last sector, +sectors or +size{K,M,G} (8192-204799, default 204799): 回车
Command (m for help): w
[root@desktop0 ~]# partprobe 

格式化

[root@desktop0 ~]# mkfs.ext4 /dev/sdc1 

7、设定开机挂载

查看uuid，加入/etc/fstab文件中,注意挂载选项必须加_netdev

[root@desktop0 ~]# blkid /dev/sdc1 
/dev/sdc1: UUID="8bd4649c-3191-4962-a8a9-08e2093bdc1c" TYPE="ext4" 
[root@desktop0 ~]# vim /etc/fstab 
...
UUID=8bd4649c-3191-4962-a8a9-08e2093bdc1c /mnt/iscsi ext4 defaults,_netdev 0 0

创建挂载点并且挂载

[root@desktop0 ~]# mkdir -p /mnt/iscsi
[root@desktop0 ~]# mount -a 
[root@desktop0 ~]# df -h
/dev/sdc1 89M 1.6M 81M 2% /mnt/iscsi

错误补救：
每次开机iscsi都会自动登录，iscsi会从/var/lib/iscsi/nodes/目录去找到发现的target去登录

[root@desktop0 ~]# ls /var/lib/iscsi/nodes/
iqn.2014-06.com.example.com:server0

彻底删除发现过的target
首先取消登录所有的target

[root@desktop0 ~]# iscsiadm -m node -u

然后指定名字删除，此时发现存储目录已经没有数据，下次也不会重新去自动登录了

[root@desktop0 ~]# iscsiadm -m node -T iqn.2014-06.com.example.com:server0 -o delete
[root@desktop0 ~]# ls /var/lib/iscsi/nodes/

然后就可以重启服务重新进行发现，登录，挂载的操作

本教程到此结束

如果有什么建议或者看不明白的地方，欢迎评论区留言或者私信本人，看到了第一时间处理。

本人为Linux菜鸟，还望Linux大神多多指教。