服务器信息：
[root@initiator ~]# cat /etc/redhat-release
CentOS release 6.6 (Final)
[root@initiator ~]# uname -a
Linux initiator 2.6.32-504.el6.x86_64 #1 SMP Wed Oct 15 04:27:16 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
[root@initiator ~]# ifconfig
eth0 Link encap:Ethernet HWaddr 00:0C:29:6A:34:88
inet addr:192.168.221.131 Bcast:192.168.221.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fe6a:3488/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:49589 errors:0 dropped:0 overruns:0 frame:0
TX packets:197750 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:36045946 (34.3 MiB) TX bytes:234344817 (223.4 MiB)
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:4 errors:0 dropped:0 overruns:0 frame:0
TX packets:4 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:276 (276.0 b) TX bytes:276 (276.0 b)
iSCSI initiator是能够使用target的客户端，通常是服务器。想要连接到iSCSI target的服务器，必须要安装iSCSI initiator的相关功能后才可以使用。其功能是：1.可以处理本地挂载磁盘上的任意文件系统。2.在使用fdisk命令分区后不需要重启系统。
FBI Warning：永远不要在LUN还挂载在客户端（发起程序）时停止服务。
要设置iSCSI initiator 必须要安装iscsi-initiator-utils才行。开始上菜。。。
[root@initiator ~]# yum search all iscsi
已加载插件：fastestmirror
Loading mirror speeds from cached hostfile
* base: mirrors.skyshe.cn
* extras: mirrors.skyshe.cn
* updates: mirrors.cqu.edu.cn
================================================================================ Matched: iscsi ================================================================================
iscsi-initiator-utils.x86_64 : iSCSI daemon and utility programs
iscsi-initiator-utils-devel.x86_64 : Development files for iscsi-initiator-utils
gpxe-bootimgs.noarch : Network boot loader images in bootable USB, CD, floppy and GRUB formats
gpxe-roms.noarch : Network boot loader roms in .rom format
gpxe-roms-qemu.noarch : Network boot loader roms supported by QEMU, .rom format
isns-utils.x86_64 : The iSNS daemon and utility programs
scsi-target-utils.x86_64 : The SCSI target daemon and utility programs
1.yum大法安装
[root@initiator ~]# yum install iscsi-initiator-utils iscsi-initiator-utils-devel -y
2.启动服务开机启动
[root@initiator ~]# service iscsid start 正在启动 iscsid： [确定]
[root@initiator ~]# chkconfig iscsi on [root@initiator ~]# chkconfig iscsid on
3.man大法查看客户端命令iscsiadm，查看示例。
EXAMPLES
Discover targets at a given IP address:
iscsiadm --mode discoverydb --type sendtargets --portal 192.168.1.10 --discover
Login, must use a node record id found by the discovery:
iscsiadm --mode node --targetname iqn.2001-05.com.doe:test --portal 192.168.1.1:3260 --login
Logout:
iscsiadm --mode node --targetname iqn.2001-05.com.doe:test --portal 192.168.1.1:3260 --logout
List node records:
iscsiadm --mode node
Display all data for a given node record:
iscsiadm --mode node --targetname iqn.2001-05.com.doe:test --portal 192.168.1.1:3260
4.根据示例中我们根据IP找到Target的限定名（iqn）。
[root@initiator ~]# iscsiadm --mode discoverydb --type sendtargets --portal 192.168.221.130 --discover 192.168.221.130:3260,1 iqn.2015-09.com.node:tgt1
--mode discoverydb:使用检测的方式进行iscsiadmin命令功能
--type sendtargets :通过iSCSI的协议，检测后面的设备所拥有的target数据
--portal :就是那台iSCSI设备的IP与端口，不写端口的默认是3260
OK。摸摸哒。找到了。
显示出目前系统上面所有的target数据，可能并未登陆：
[root@initiator ~]# iscsiadm -m node 192.168.221.130:3260,1 iqn.2015-09.com.node:tgt1
默认配置都在defaults文件中
[root@initiator ~]# ll -R /var/lib/iscsi/nodes/ /var/lib/iscsi/nodes/: 总用量 4 drw-------. 3 root root 4096 9月 22 23:50 iqn.2015-09.com.node:tgt1 /var/lib/iscsi/nodes/iqn.2015-09.com.node:tgt1: 总用量 4 drw-------. 2 root root 4096 9月 22 23:50 192.168.221.130,3260,1 /var/lib/iscsi/nodes/iqn.2015-09.com.node:tgt1/192.168.221.130,3260,1: 总用量 4 -rw-------. 1 root root 2045 9月 22 23:50 default
6.要登录就用下面的命令来连接一台LUN到我们本地系统中，这会与服务器验证并允许我们登录LUN。
[root@initiator ~]# iscsiadm --mode node --targetname iqn.2015-09.com.node:tgt1 --portal 192.168.221.130:3260 --login Logging in to [iface: default, target: iqn.2015-09.com.node:tgt1, portal: 192.168.221.130,3260] (multiple) Login to [iface: default, target: iqn.2015-09.com.node:tgt1, portal: 192.168.221.130,3260] successful.
--targetname：target名字
--login :登陆
warning：
登出使用登录命令并在命令的最后使用logout来替换
[root@initiator ~]# iscsiadm --mode node --targetname iqn.2015-09.com.node:tgt1 --portal 192.168.221.130:3260 --logout
Logging out of session [sid: 1, target: iqn.2015-09.com.node:tgt1, portal: 192.168.221.130,3260]
Logout of [sid: 1, target: iqn.2015-09.com.node:tgt1, portal: 192.168.221.130,3260] successful.
7.登陆后，显示特定target的所有数据
[root@initiator ~]# iscsiadm --mode node --targetname iqn.2015-09.com.node:tgt1 --portal 192.168.221.130:3260 # BEGIN RECORD 6.2.0-873.13.el6 node.name = iqn.2015-09.com.node:tgt1 node.tpgt = 1 node.startup = automatic node.leading_login = No iface.hwaddress = <empty> iface.ipaddress = <empty> iface.iscsi_ifacename = default iface.net_ifacename = <empty> iface.transport_name = tcp iface.initiatorname = <empty> iface.state = <empty> iface.vlan_id = 0 iface.vlan_priority = 0 iface.vlan_state = <empty> iface.iface_num = 0 iface.mtu = 0 iface.port = 0 iface.bootproto = <empty> iface.subnet_mask = <empty> iface.gateway = <empty> iface.dhcp_alt_client_id_state = <empty> iface.dhcp_alt_client_id = <empty> iface.dhcp_dns = <empty> iface.dhcp_learn_iqn = <empty> iface.dhcp_req_vendor_id_state = <empty> iface.dhcp_vendor_id_state = <empty> iface.dhcp_vendor_id = <empty> iface.dhcp_slp_da = <empty> iface.fragmentation = <empty> iface.gratuitous_arp = <empty> iface.incoming_forwarding = <empty> iface.tos_state = <empty> iface.tos = 0 iface.ttl = 0
........................
8.接着列出使用的磁盘，fdisk会列出所有的登录认证过的磁盘
[root@initiator ~]# fdisk -l Disk /dev/sda: 21.5 GB, 21474836480 bytes 255 heads, 63 sectors/track, 2610 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00074c40 Device Boot Start End Blocks Id System /dev/sda1 * 1 2040 16384000 83 Linux /dev/sda2 2040 2611 4586496 82 Linux swap / Solaris Disk /dev/sdb: 5368 MB, 5368709120 bytes 166 heads, 62 sectors/track, 1018 cylinders Units = cylinders of 10292 * 512 = 5269504 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Disk /dev/sdc: 5368 MB, 5368709120 bytes 166 heads, 62 sectors/track, 1018 cylinders Units = cylinders of 10292 * 512 = 5269504 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Disk /dev/sdd: 5368 MB, 5368709120 bytes 166 heads, 62 sectors/track, 1018 cylinders Units = cylinders of 10292 * 512 = 5269504 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Disk /dev/sde: 4294 MB, 4294967296 bytes 133 heads, 62 sectors/track, 1017 cylinders Units = cylinders of 8246 * 512 = 4221952 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000
9.运行fdisk命令来创建一个新的分区，在使用fdisk创建新分区之后，我们无需重启，就像使用我们本地的文件系统一样就行。因为这个将远程共享存储挂载到本地了。
[root@initiator ~]# fdisk -cu /dev/sdb
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel with disk identifier 0x58426cdd.
Changes will remain in memory only, until you decide to write them.
After that, of course, the previous content won't be recoverable.
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 1
First sector (2048-10485759, default 2048):
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-10485759, default 10485759):
Using default value 10485759
Command (m for help): t
Selected partition 1
Hex code (type L to list codes): 83
Command (m for help): p
Disk /dev/sdb: 5368 MB, 5368709120 bytes
166 heads, 62 sectors/track, 1018 cylinders, total 10485760 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x58426cdd
Device Boot Start End Blocks Id System
/dev/sdb1 2048 10485759 5241856 83 Linux
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
为所欲为的格式化新创建的分区
[root@initiator ~]# mkfs.ext4 /dev/sdb1 mke2fs 1.41.12 (17-May-2010) 文件系统标签= 操作系统:Linux 块大小=4096 (log=2) 分块大小=4096 (log=2) Stride=0 blocks, Stripe width=0 blocks 327680 inodes, 1310464 blocks 65523 blocks (5.00%) reserved for the super user 第一个数据块=0 Maximum filesystem blocks=1342177280 40 block groups 32768 blocks per group, 32768 fragments per group 8192 inodes per group Superblock backups stored on blocks: 32768, 98304, 163840, 229376, 294912, 819200, 884736 正在写入inode表: 完成 Creating journal (32768 blocks): 完成 Writing superblocks and filesystem accounting information: 完成 This filesystem will be automatically checked every 25 mounts or 180 days, whichever comes first. Use tune2fs -c or -i to override.
10. 创建一个目录来挂载新创建的分区
[root@initiator ~]# mkdir /mnt/iscsi [root@initiator ~]# mount /dev/sdb1 /mnt/iscsi/
[root@initiator ~]# ls -l /mnt/iscsi/
总用量 16
drwx------. 2 root root 16384 9月 23 00:38 lost+found
让我们看看挂载点
[root@initiator ~]# df -Th //-T 输出文件系统类型 -h以宜读的方式显示大小 Filesystem Type Size Used Avail Use% Mounted on /dev/sda1 ext4 16G 968M 14G 7% / tmpfs tmpfs 491M 0 491M 0% /dev/shm /dev/sdb1 ext4 4.8G 10M 4.6G 1% /mnt/iscsi
要想永久挂载么，当然得东fsab的刀子
[root@initiator ~]# vim /etc/fstab [root@initiator ~]# cat /etc/fstab # # /etc/fstab # Created by anaconda on Tue Sep 22 20:53:15 2015 # # Accessible filesystems, by reference, are maintained under '/dev/disk' # See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info # UUID=0466fb2b-f1ab-4666-bb8f-2e7d008f5b55 / ext4 defaults 1 1 UUID=1766dc2c-509e-4547-b647-ec42e61e9223 swap swap defaults 0 0 tmpfs /dev/shm tmpfs defaults 0 0 devpts /dev/pts devpts gid=5,mode=620 0 0 sysfs /sys sysfs defaults 0 0 proc /proc proc defaults 0 0 /dev/sdb1 /mnt/iscsi ext4 defaults,_netdev 0 0
_netdev，说明这是一个网络设备。
检查我们fstab文件是否有错误。
[root@initiator ~]# mount -av //-a 所有挂载点 -v冗余模式 mount: tmpfs already mounted on /dev/shm mount: devpts already mounted on /dev/pts mount: sysfs already mounted on /sys mount: proc already mounted on /proc mount: /dev/sdb1 already mounted on /mnt/iscsi nothing was mounted
beautiful，尽情使用吧。。。。。
参考资料
linux中国：https://linux.cn/ 我最喜欢的linux中文网站
使用iSCSI Target创建集中式安全存储（一）：https://linux.cn/article-4971-1.html
鸟哥的LINUX私房菜--服务器架设篇