操作系统版本：
Red Hat Enterprise Linux Server release 6.8

通过系统自带的iscsi 实现：

软件要求：
服务端：scsi-target-utils.x86_64
客户端：iscsi-initiator-utils.x86_64

测试环境地址配置情况：

eth0 pub 业务网络
eth1 pri 心跳网络
eth2 iscsi存储网络

2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:0c:29:e7:53:a6 brd ff:ff:ff:ff:ff:ff
    inet 192.0.2.200/24 brd 192.0.2.255 scope global eth0
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fee7:53a6/64 scope link 
       valid_lft forever preferred_lft forever
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:0c:29:e7:53:b0 brd ff:ff:ff:ff:ff:ff
    inet 10.0.2.200/24 brd 10.0.2.255 scope global eth1
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fee7:53b0/64 scope link 
       valid_lft forever preferred_lft forever
4: eth2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:0c:29:e7:53:ba brd ff:ff:ff:ff:ff:ff
    inet 2.0.2.200/24 brd 2.0.2.255 scope global eth2
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fee7:53ba/64 scope link 
       valid_lft forever preferred_lft forever

ora01 主机 /dev/sdc1，通过iscsi 映射给ora02 主机。

主机ora01 配置：

[root@ora01 ~]# cat /etc/tgt/targets.conf
<target iqn.2019-05.disk.ora-san-net:ocr>
        backing-store /dev/sdc1
        initiator-address 2.0.2.202
</target>

[root@ora01 ~]# tgt-admin -s
Target 1: iqn.2019-05.disk.ora-san-net:ocr
    System information:
        Driver: iscsi
        State: ready
    I_T nexus information:
        I_T nexus: 2
            Initiator: iqn.1988-12.com.oracle:9cd059a2d728
            Connection: 0
                IP Address: 2.0.2.202
    LUN information:
        LUN: 0
            Type: controller
            SCSI ID: IET     00010000
            SCSI SN: beaf10
            Size: 0 MB, Block size: 1
            Online: Yes
            Removable media: No
            Prevent removal: No
            Readonly: No
            Backing store type: null
            Backing store path: None
            Backing store flags: 
        LUN: 1
            Type: disk
            SCSI ID: IET     00010001
            SCSI SN: beaf11
            Size: 1069 MB, Block size: 512
            Online: Yes
            Removable media: No
            Prevent removal: No
            Readonly: No
            Backing store type: rdwr
            Backing store path: /dev/sdc1
            Backing store flags: 
    Account information:
    ACL information:
        2.0.2.202

ora02 主机配置

[root@ora02 tgt]# chkconfig iscsid on
[root@ora02 tgt]# iscsiadm -m discovery -t sendtargets -p 2.0.2.200
[root@ora02 tgt]# iscsiadm -m node
[root@ora02 tgt]# iscsiadm -m node --login -T iqn.2019-05.disk.ora-san-net:ocr
[root@ora02 tgt]# iscsiadm -m session

环境检查，确认

ora01

[root@ora01 ~]# oracleasm querydisk /dev/sdc1
Device "/dev/sdc1" is marked an ASM disk with the label "DATA01"

ora02:

[root@ora02 tgt]# oracleasm querydisk /dev/sdf
Device "/dev/sdf" is marked an ASM disk with the label "DATA01"