How To Configure Iscsi Storage On Redhat Linux

Show current installed redhat version and update

[root@BobTestBox ~]# cat /etc/redhat-release

Red Hat Enterprise Linux Server release 5.7 (Tikanga)

Display Architecture

[root@BobTestBox ~]# getconf LONG_BIT

64

Check isci initiator installed or not (You need iscsi-initiator-utils-6.2.0.742-0.6.el5 or greater)

[root@BobTestBox ~]# rpm -qa | grep -i iscsi

iscsi-initiator-utils-6.2.0.872-10.el5

Display interfaces and IP address details

[root@BobTestBox ~]# ifconfig -a | more

eth0 Link encap:Ethernet HWaddr 00:50:56:AB:00:E7

inet addr:172.28.*.* Bcast:172.28.12.255 Mask:255.255.255.0

UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1

RX packets:2503 errors:0 dropped:0 overruns:0 frame:0

TX packets:838 errors:0 dropped:0 overruns:0 carrier:0

collisions:0 txqueuelen:1000

RX bytes:196784 (192.1 KiB) TX bytes:98212 (95.9 KiB)

eth1 Link encap:Ethernet HWaddr 00:50:56:AB:00:E8

inet addr:172.28.*.* Bcast:172.28.40.255 Mask:255.255.255.0

UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1

RX packets:4237 errors:0 dropped:0 overruns:0 frame:0

TX packets:3807 errors:0 dropped:0 overruns:0 carrier:0

collisions:0 txqueuelen:1000

RX bytes:966177 (943.5 KiB) TX bytes:359247 (350.8 KiB)

eth2 Link encap:Ethernet HWaddr 00:50:56:AB:01:00

inet addr:172.28.*.* Bcast:172.28.40.255 Mask:255.255.255.0

UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1

RX packets:4387 errors:0 dropped:0 overruns:0 frame:0

TX packets:3960 errors:0 dropped:0 overruns:0 carrier:0

collisions:0 txqueuelen:1000

RX bytes:894415 (873.4 KiB) TX bytes:384013 (375.0 KiB)

lo Link encap:Local Loopback

inet addr:127.0.0.1 Mask:255.0.0.0

UP LOOPBACK RUNNING MTU:16436 Metric:1

RX packets:10 errors:0 dropped:0 overruns:0 frame:0

TX packets:10 errors:0 dropped:0 overruns:0 carrier:0

collisions:0 txqueuelen:0

RX bytes:660 (660.0 b) TX bytes:660 (660.0 b)

Creating the interface files for MPIO

[root@BobTestBox ~]# iscsiadm -m iface -I eth1 -o new

New interface eth1 added

[root@BobTestBox ~]# iscsiadm -m iface -I eth2 -o new

New interface eth2 added

Updating the interface name for each port

[root@BobTestBox ~]# iscsiadm -m iface -I eth1 -o update -n iface.net_ifacename -v eth1

eth1 updated.

[root@BobTestBox ~]# iscsiadm -m iface -I eth2 -o update -n iface.net_ifacename -v eth2

eth2 updated.

[root@BobTestBox ~]# cat /var/lib/iscsi/ifaces/eth1

# BEGIN RECORD 2.0-872

iface.iscsi_ifacename = eth1

iface.net_ifacename = eth1

iface.transport_name = tcp

# END RECORD

[root@localhost ~]# cat /var/lib/iscsi/ifaces/eth2

# BEGIN RECORD 2.0-872

iface.iscsi_ifacename = eth2

iface.net_ifacename = eth2

iface.transport_name = tcp

# END RECORD

Iscsi target Discovering using iscsiadm command

[root@BobTestBox ~]# iscsiadm -m discovery -t st -p 172.28.*.*:3260

172.28.*.*:3260,1 iqn.2001-05.com.equallogic:0-8a0906-a146b2a07-57858e634784f7b0-bobrhel

172.28.*.*:3260,1 iqn.2001-05.com.equallogic:0-8a0906-a146b2a07-57858e634784f7b0-bobrhel

Logging into target ( You have option to login individually also)

[root@BobTestBox ~]# iscsiadm -m node -l

Logging in to [iface: eth2, target: iqn.2001-05.com.equallogic:0-8a0906-a146b2a07-57858e634784f7b0-bobrhel, portal: 172.28.*.*,3260]

Logging in to [iface: default, target: iqn.2001-05.com.equallogic:0-8a0906-a146b2a07-57858e634784f7b0-bobrhel, portal: 172.28.*.*,3260]

Logging in to [iface: eth1, target: iqn.2001-05.com.equallogic:0-8a0906-a146b2a07-57858e634784f7b0-bobrhel, portal: 172.28.*.*,3260]

Login to [iface: eth2, target: iqn.2001-05.com.equallogic:0-8a0906-a146b2a07-57858e634784f7b0-bobrhel, portal: 172.28.*.*,3260] successful.

Login to [iface: default, target: iqn.2001-05.com.equallogic:0-8a0906-a146b2a07-57858e634784f7b0-bobrhel, portal: 172.28.*.*,3260] successful.

Login to [iface: eth1, target: iqn.2001-05.com.equallogic:0-8a0906-a146b2a07-57858e634784f7b0-bobrhel, portal: 172.28.*.*,3260] successful.

[root@BobTestBox ~]#

Display scsi attached device

[root@BobTestBox ~]# cat /proc/scsi/scsi

Attached devices:

Host: scsi0 Channel: 00 Id: 00 Lun: 00

Vendor: VMware Model: Virtual disk Rev: 1.0

Type: Direct-Access ANSI SCSI revision: 02

Host: scsi7 Channel: 00 Id: 00 Lun: 00

Vendor: EQLOGIC Model: 100E-00 Rev: 5.2

Type: Direct-Access ANSI SCSI revision: 05

Host: scsi6 Channel: 00 Id: 00 Lun: 00

Vendor: EQLOGIC Model: 100E-00 Rev: 5.2

Type: Direct-Access ANSI SCSI revision: 05

[root@BobTestBox ~]#

Below command will display Iscsi session details

[root@BobTestBox ~]# iscsiadm -m session

tcp: [6] 172.28.*.*:3260,1 iqn.2001-05.com.equallogic:0-8a0906-a146b2a07-57858e634784f7b0-bobrhel

tcp: [7] 172.28.*.*:3260,1 iqn.2001-05.com.equallogic:0-8a0906-a146b2a07-57858e634784f7b0-bobrhel

root@BobTestBox ~]#

Display Disk details

Below command will display linux disk details that are known to kernel

[root@BobTestBox ~]# fdisk -l

Disk /dev/sda: 5368 MB, 5368709120 bytes

255 heads, 63 sectors/track, 652 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System

/dev/sda1 * 1 574 4610623+ 83 Linux

/dev/sda2 575 652 626535 82 Linux swap / Solaris

Disk /dev/dm-0: 1085 MB, 1085276160 bytes

255 heads, 63 sectors/track, 131 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Disk /dev/dm-0 doesn’t contain a valid partition table

Disk /dev/sde: 1085 MB, 1085276160 bytes

34 heads, 61 sectors/track, 1022 cylinders

Units = cylinders of 2074 * 512 = 1061888 bytes

Disk /dev/sde doesn’t contain a valid partition table

Disk /dev/sdf: 1085 MB, 1085276160 bytes

34 heads, 61 sectors/track, 1022 cylinders

Units = cylinders of 2074 * 512 = 1061888 bytes

Disk /dev/sdf doesn’t contain a valid partition table

[root@BobTestBox ~]#

Checking whether Equallogic Hit installed ( I have already installed HIT Kit 1.0.0- #rpm –ivh equallogic-host-tools-1.0.0-1.el5.x86_64.rpm

[root@BobTestBox ~]# rpm -qa | grep -i equa

equallogic-host-tools-1.0.0-1.el5

Hit requires dkms 1.95 (Dynamic kernel module support) installed. ( I have already installed dkms - #rpm –ivh dkms-1.95.32-1.noarch.rpm )

[root@BobTestBox ~]# rpm -qa | grep -i dkms

dkms-1.95.32-1

Dkms module can be download from http://linux.dell.com/dkms/testing/permalink

Restarting EHCMD service (dell multipath module )

[root@BobTestBox ~]# /etc/init.d/ehcmd restart

Stopping ehcmd: [FAILED]

Starting ehcmd: [ OK ]

Restarting Multipath deamon ( You can set alias ,uuid , device details , blacklist node in multhipath.conf file before restarting)

[root@BobTestBox ~]# /etc/init.d/multipathd restart

Stopping multipathd daemon: [FAILED]

Starting multipathd daemon: [ OK ]

[root@BobTestBox ~]#

Display multhipath details

[root@BobTestBox ~]# multipath -ll

Bob_rhel_lun () dm-0 EQLOGIC,100E-00

[size=1.0G][features=1 queue_if_no_path][hwhandler=0][rw]

\_ round-robin 0 [prio=2][enabled]

\_ 3:0:0:0 sdc 8:32 [active][ready]

\_ 1:0:0:0 sdd 8:48 [active][ready]

[root@BobTestBox ~]#

Device mapper target device status

[root@BobTestBox ~]# dmsetup ls --target=multipath

Bob_rhel_lun (253, 0)

[root@BobTestBox ~]#

Mounting the the filesystem. I have already formated the filesystem using mkfs command (mkfs.ext3 /dev/mapper/Bob_rhel_lun)

[root@BobTestBox ~]# mount /dev/mapper/Bob_rhel_lun /data

Display disk usage

[root@BobTestBox ~]# df -h

Filesystem Size Used Avail Use% Mounted on

/dev/sda1 4.3G 2.7G 1.5G 66% /

tmpfs 502M 0 502M 0% /dev/shm

/dev/mapper/Bob_rhel_lun 1019M 34M 934M 4% /data

[root@BobTestBox ~]#

For persistence on reboot , added mount point to fstab file

[root@BobTestBox ~]# cat /etc/fstab

LABEL=/ / ext3 defaults 1 1

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

LABEL=SWAP-sda2 swap swap defaults 0 0

/dev/mapper/Bob_rhel_lun /data ext3 defaults 0 0

[root@BobTestBox ~]#