Fedora 40: Install iSCSI as Storage Server

Introduction

In this article, we will explore the what, who, where, when, why, and how of Network File System (NFS) as Storage Server functionality on the Fedora 40 platform, so let's get started.

Overview Configure Target (Targetcli) Configure Target (tgt) Configure Initiator

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• Overview
• Configure Target (Targetcli)
• Configure Target (tgt)
• Configure Initiator

Overview

What

iSCSI Target Configuration using Targetcli involves setting up storage devices to be accessible over a network. It includes creating targets, setting up LUNs (Logical Unit Numbers), and managing access.

Who

System administrators and IT professionals responsible for managing and configuring storage networks and resources.

Where

This configuration is applicable in data centers, enterprise environments, or any setup requiring networked storage solutions.

When

When you need to provide centralized storage resources accessible over a network, iSCSI target configuration becomes crucial.

Why

Configuring iSCSI targets has several pros and cons:

Pros	Cons
Centralized storage management.	Network dependency can lead to latency issues.
Scalability for large environments.	Requires careful network planning and configuration.
Cost-effective compared to other storage solutions.	Performance can be affected by network congestion.
Flexibility in storage allocation.	Potential security risks if not properly managed.

How

Follow these steps to configure an iSCSI target using Targetcli:

Step 1	Install Targetcli: sudo apt-get install targetcli
Step 2	Create a backing store: targetcli backstores/fileio create mybackstore /path/to/file.img 10G
Step 3	Create an iSCSI target: targetcli iscsi/ create iqn.2024-11.com.example:target
Step 4	Assign LUNs: targetcli iscsi/iqn.2024-11.com.example:target/tpg1/luns/ create /backstores/fileio/mybackstore

Consequences

Setting up an iSCSI target using Targetcli can lead to several consequences:

Positive	Improved storage management. Better resource allocation. Scalability and flexibility. Cost efficiency.
Negative	Possible network latency. Complex configuration processes. Potential security vulnerabilities. Dependency on network stability.

Conclusion

Configuring iSCSI targets using Targetcli offers a robust and flexible solution for networked storage. While it comes with its challenges, the benefits of centralized management, scalability, and cost-effectiveness make it a compelling choice for many organizations. Proper planning and security measures are essential to mitigate potential risks and ensure optimal performance.

iSCSI : Configure Target (Targetcli)

Configure Storage Server with iSCSI. Storage server with iSCSI on network is called iSCSI Target, Client Host that connects to iSCSI Target is called iSCSI Initiator. This example is based on the environment like follows.

+----------------------+          |          +-------------------------+
| [   iSCSI Target   ] |10.0.0.30 | 10.0.0.51|    [ iSCSI Initiator ]  |
|  dlp.bizantum.lab    +----------+----------+   node01.bizantum.lab   |
|                      |                     |                         |
+----------------------+                     +-------------------------+
              

Step [1]Install administration tool.

                     
[root@dlp ~]# dnf -y install targetcli
                    
                

Step [2]Configure iSCSI Target. For example, Create a disk-image under the [/var/lib/iscsi_disks] directory and set it as a SCSI device.

                     
# create a directory
[root@dlp ~]# mkdir /var/lib/iscsi_disks
# enter to the admin console
[root@dlp ~]# targetcli
targetcli shell version 2.1.58
Copyright 2011-2013 by Datera, Inc and others.
For help on commands, type 'help'.

/> cd /backstores/fileio 

# create a disk-image with the name [disk01] on [/var/lib/iscsi_disks/disk01.img] with 10G
/backstores/fileio> create disk01 /var/lib/iscsi_disks/disk01.img 10G 
Created fileio disk01 with size 10737418240
/backstores/fileio> cd /iscsi 

# create a target
# naming rule : [ iqn.(year)-(month).(reverse of domain name):(any name you like) ]
/iscsi> create iqn.2024-04.lab.bizantum:dlp.target01 
Created target iqn.2024-04.lab.bizantum:dlp.target01.
Created TPG 1.
Global pref auto_add_default_portal=true
Created default portal listening on all IPs (0.0.0.0), port 3260.
/iscsi> cd iqn.2024-04.lab.bizantum:dlp.target01/tpg1 

# enable authentication
/iscsi/iqn.20...target01/tpg1> set attribute authentication=1 
Parameter authentication is now '1'.
/iscsi/iqn.20...target01/tpg1> cd luns 

# set LUN
/iscsi/iqn.20...t01/tpg1/luns> create /backstores/fileio/disk01 
Created LUN 0.
/iscsi/iqn.20...t01/tpg1/luns> cd ../acls 

# set ACL (it's the IQN of an initiator you permit to connect)
/iscsi/iqn.20...t01/tpg1/acls> create iqn.2024-04.lab.bizantum:node01.initiator 
Created Node ACL for iqn.2024-04.lab.bizantum:node01.initiator
Created mapped LUN 0.
/iscsi/iqn.20...t01/tpg1/acls> cd iqn.2024-04.lab.bizantum:node01.initiator 

# set UserID and Password for authentication
/iscsi/iqn.20...w.initiator> set auth userid=username 
Parameter userid is now 'username'.
/iscsi/iqn.20...w.initiator> set auth password=password 
Parameter password is now 'password'.
/iscsi/iqn.20...w.initiator> exit 
Global pref auto_save_on_exit=true
Configuration saved to /etc/target/saveconfig.json

# after configuration above, the target enters in listening like follows
[root@dlp ~]# ss -napt | grep 3260
LISTEN 0      256          0.0.0.0:3260       0.0.0.0:*

[root@dlp ~]# systemctl enable target
                    
                

Step [3]If Firewalld is running, allow iSCSI Target service.

                    
[root@dlp ~]# firewall-cmd --add-service=iscsi-target
success
[root@dlp ~]# firewall-cmd --runtime-to-permanent
success
                    
                

iSCSI : Configure Target (tgt)

Configure Storage Server with iSCSI. This is the example of configuring iSCSI Target with scsi-target-utils. (tgt) Storage server with iSCSI on network is called iSCSI Target, Client Host that connects to iSCSI Target is called iSCSI Initiator. This example is based on the environment like follows.

+----------------------+          |          +-------------------------+
| [   iSCSI Target   ] |10.0.0.30 | 10.0.0.51|   [  iSCSI Initiator  ] |
|   dlp.bizantum.lab   +----------+----------+   node01.bizantum.lab   |
|                      |                     |                         |
+----------------------+                     +-------------------------+
              

Step [1]Install administration tools.

                     
[root@dlp ~]# dnf -y install scsi-target-utils
                    
                

Step [2] Configure iSCSI Target. For example, create an disk-image under the [/var/lib/iscsi_disks] directory and set it as a SCSI device.

                     
# create a disk image
[root@dlp ~]# mkdir /var/lib/iscsi_disks
[root@dlp ~]# dd if=/dev/zero of=/var/lib/iscsi_disks/disk01.img count=0 bs=1 seek=10G
[root@dlp ~]# vi /etc/tgt/conf.d/target01.conf
# create new
# if you set some devices, add - and set the same way with follows
# naming rule : [ iqn.(year)-(month).(reverse of domain name):(any name you like) ]
<target iqn.2024-04.lab.bizantum:dlp.target01>
    # provided device as a iSCSI target
    backing-store /var/lib/iscsi_disks/disk01.img
    # iSCSI Initiator's IQN you allow to connect
    initiator-name iqn.2024-04.lab.bizantum:node01.initiator
    # authentication info ( set anyone you like for "username", "password" )
	incominguser username password
</target> 
                    
                

Step [3]If SELinux is enabled, change SELinux Context.

                    
[root@dlp ~]# dnf -y install policycoreutils-python-utils
[root@dlp ~]# chcon -R -t tgtd_var_lib_t /var/lib/iscsi_disks
[root@dlp ~]# semanage fcontext -a -t tgtd_var_lib_t /var/lib/iscsi_disks
                    
                

Step [4]If SELinux is enabled, change SELinux Context.

                    
[root@dlp ~]# firewall-cmd --add-service=iscsi-target
success
[root@dlp ~]# firewall-cmd --runtime-to-permanent
success
                    
                

Step [5]Start tgtd and verify status.

                    
[root@dlp ~]# systemctl enable --now tgtd
# show status
[root@dlp ~]# tgtadm --mode target --op show
Target 1: iqn.2024-04.lab.bizantum:dlp.target01
    System information:
        Driver: iscsi
        State: ready
    I_T nexus information:
    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
            SWP: No
            Thin-provisioning: No
            Backing store type: null
            Backing store path: None
            Backing store flags:
        LUN: 1
            Type: disk
            SCSI ID: IET     00010001
            SCSI SN: beaf11
            Size: 10737 MB, Block size: 512
            Online: Yes
            Removable media: No
            Prevent removal: No
            Readonly: No
            SWP: No
            Thin-provisioning: No
            Backing store type: rdwr
            Backing store path: /var/lib/iscsi_disks/disk02.img
            Backing store flags:
    Account information:
        username
    ACL information:
        ALL
        iqn.2024-04.lab.bizantum:node01.initiator
                    
                

iSCSI : Configure Initiator

Configure iSCSI Initiator. This example is based on the environment like follows.

+----------------------+          |          +-------------------------+
| [   iSCSI Target   ] |10.0.0.30 | 10.0.0.51|   [ iSCSI Initiator  ]  |
|   dlp.bizantum.lab   +----------+----------+   node01.bizantum.lab   |
|                      |                     |                         |
+----------------------+                     +-------------------------+
              

Step [1]Configure iSCSI Initiator to connect to iSCSI Target.

                     
[root@node01 ~]# dnf -y install iscsi-initiator-utils
[root@node01 ~]# vi /etc/iscsi/initiatorname.iscsi
# set to the same IQN you set on the iSCSI target server
InitiatorName=iqn.2024-04.lab.bizantum:node01.initiator
[root@node01 ~]# vi /etc/iscsi/iscsid.conf
# line 67 : uncomment
node.session.auth.authmethod = CHAP
# line 79,80 : uncomment and specify the username and password you set on the iSCSI target server
node.session.auth.username = username
node.session.auth.password = password
# discover target
[root@node01 ~]# iscsiadm -m discovery -t sendtargets -p 10.0.0.30
10.0.0.30:3260,1 iqn.2024-04.lab.bizantum:dlp.target01

# confirm status after discovery
[root@node01 ~]# iscsiadm -m node -o show
# BEGIN RECORD 6.2.1.9
node.name = iqn.2024-04.lab.bizantum:dlp.target01
node.tpgt = 1
node.startup = automatic
node.leading_login = No
iface.iscsi_ifacename = default
.....
.....
node.conn[0].iscsi.DataDigest = None
node.conn[0].iscsi.IFMarker = No
node.conn[0].iscsi.OFMarker = No
# END RECORD

# login to the target
# if logout ⇒ iscsiadm --mode node --logoutall=all
[root@node01 ~]# iscsiadm -m node --login -p 10.0.0.30
Logging in to [iface: default, target: iqn.2024-04.lab.bizantum:dlp.target01, portal: 10.0.0.30,3260]
Login to [iface: default, target: iqn.2024-04.lab.bizantum:dlp.target01, portal: 10.0.0.30,3260] successful.

# confirm the established session
[root@node01 ~]# iscsiadm -m session -o show
tcp: [1] 10.0.0.30:3260,1 iqn.2024-04.lab.bizantum:dlp.target01 (non-flash)
# confirm the partitions
[root@node01 ~]# cat /proc/partitions
major minor  #blocks  name

 252        0   31457280 sda
 252        1       1024 sda1
 252        2    1048576 sda2
 252        3   30405632 sda3
 253        0   15728640 dm-0
 251        0    3992576 zram0
   8        0   10485760 sdb
# added new device provided from the target server as [sdb]
                    
                

Step [2]After setting iSCSI device, configure on Initiator to use it like follows.

                     
# create label
[root@node01 ~]# parted --script /dev/sdb "mklabel gpt"
# create partition
[root@node01 ~]# parted --script /dev/sdb "mkpart primary 0% 100%"
# format with XFS
[root@node01 ~]# mkfs.xfs /dev/sdb1
meta-data=/dev/sdb1              isize=512    agcount=4, agsize=655232 blks
         =                       sectsz=4096  attr=2, projid32bit=1
         =                       crc=1        finobt=1, sparse=1, rmapbt=0
         =                       reflink=1    bigtime=1 inobtcount=1
data     =                       bsize=4096   blocks=2620928, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0, ftype=1
log      =internal log           bsize=4096   blocks=16384, version=2
         =                       sectsz=4096  sunit=1 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0

[root@node01 ~]# mount /dev/sdb1 /mnt
[root@node01 ~]# df -hT
Filesystem              Type      Size  Used Avail Use% Mounted on
/dev/mapper/fedora-root xfs        15G  1.9G   14G  13% /
devtmpfs                devtmpfs  4.0M     0  4.0M   0% /dev
tmpfs                   tmpfs     2.0G     0  2.0G   0% /dev/shm
tmpfs                   tmpfs     782M  1.1M  781M   1% /run
tmpfs                   tmpfs     2.0G     0  2.0G   0% /tmp
/dev/sda2               xfs       960M  344M  617M  36% /boot
tmpfs                   tmpfs     391M  4.0K  391M   1% /run/user/0
/dev/sdb1               xfs        10G  227M  9.8G   3% /mnt