Installing and Configuring NAS on Debian Jessie
What's up folks, here I'll show how to configure NAS on Debian Jessie and their clients.
Network-attached storage (NAS) is file-level computer data storage server connected to a computer network providing data access to a heterogeneous group of clients. NAS not only operates as a file server, but is specialized for this task either by its hardware, software, or configuration of those elements. NAS is often manufactured as a computer appliance – a specialized computer built from the ground up for storing and serving files – rather than simply a general purpose computer being used for the role.
As of 2010 NAS devices began gaining popularity as a convenient method of sharing files among multiple computers. Potential benefits of dedicated network-attached storage, compared to general-purpose servers also serving files, include faster data access, easier administration, and simple configuration.
NAS systems are networked appliances which contain one or more hard drives, often arranged into logical, redundant storage containers or RAID. Network-attached storage removes the responsibility of file serving from other servers on the network. They typically provide access to files using network file sharing protocols such as NFS, SMB/CIFS, or AFP.
Note that hard drives with “NAS” in their name are functionally similar to other drives but may have different firmware, vibration tolerance, or power dissipation to make them more suitable for use in RAID arrays, which are sometimes used in NAS implementations. For example, some NAS versions of drives support a command extension to allow extended error recovery to be disabled. In a non-RAID application, it may be important for a disk drive to go to great lengths to successfully read a problematic storage block, even if it takes several seconds. In an appropriately configured RAID array, a single bad block on a single drive can be recovered completely via the redundancy encoded across the RAID set. If a drive spends several seconds executing extensive retries it might cause the RAID controller to flag the drive as “down” whereas if it simply replied promptly that the block of data had a checksum error, the RAID controller would use the redundant data on the other drives to correct the error and continue without any problem. Such a “NAS” SATA hard disk drive can be used as an internal PC hard drive, without any problems or adjustments needed, as it simply supports additional options and may possibly be built to a higher quality standard (particularly if accompanied by a higher quoted MTBF figure and higher price) than a regular consumer drive.
What we shall use here:
- NAS Server: Debian Jessie
- IP: 10.101.0.100/24
- Name: nas
- Disk: /dev/sdb 100 GB
- Client Debian Jessie
- IP: 10.101.0.102/24
- Name: client01
- Client configuration Path: /etc/iscsi
- Client CentOS 7.1
- IP: 10.101.0.104/24
- Name: client02
- Client configuration Path: /var/lib/iscsi
We need to update the repositories and upgrade the system as follows
aptitude update && aptitude dist-upgrade -y
We need to install the prerequisites to use the NAS
aptitude install iscsitarget iscsitarget-dkms lvm2 -y
Now we need to rebuild the modules dependences
depmod -a
Let's load the iscsi module
modprobe iscsi_trgt
Let's put the iscsi module to be launched in the boot time.
echo "iscsi_trgt">> /etc/modules
Now let's reboot the server.
reboot
Now we can get information about the iscsi devices and other thinks about it in
cat /proc/net/iet/session /proc/net/iet/volume
Now we need to set the LVM flag in the second disk
pvcreate -v /dev/sdb
Now we need to create the volume group to afterwards create the logical volume.
vgcreate -v STORAGE /dev/sdb
Now let's create a logical volume that will be used as a LUN by client.
lvcreate -v -L 7G -n lun0 STORAGE
Let's make a backup of the ietd configuration file that controls the LUNs
cp -a /etc/iet/ietd.conf{,.bkp}
Now let's clean up the file.
cat /dev/null > /etc/iet/ietd.conf
Now we can
vim /etc/iet/ietd.conf ## A target definition and the target name. The targets name (the iSCSI Qualified Name ) # must be a globally unique name (as defined by the iSCSI standard) and has to start # with iqn followed by a single dot like this # Target iqn.<yyyy-mm>.<tld.domain.some.host>[:<identifier>] e.g (Target iqn.2004-07.com.example.host:storage.disk2.sys1.xyz) Target iqn.2015-04.br.com.douglasqsantos:storage.lun0 ## This assigns an optional <aliasname> to the target. Alias LUN0 ## The <username> and <password> used to authenticate the iSCSI initiators to this target. # It may be different from the username and password in section GLOBAL OPTIONS, which is # used for discovery IncomingUser usuario senha ## The <username> and <password> used to authenticate this iSCSI target to initiators. # Only one OutgoingUser per target is supported. It may be different from the username # and password in section GLOBAL OPTIONS, which is used for discovery. OutgoingUser ## Lun <lun> Path=<device>,Type=(fileio|blockio)[,ScsiId=<scsi_id>][,ScsiSN=<scsi_sn>][,IOMode=(wb|ro)] | Sectors=<size>,Type=nullio # Parameters after <lun> should not contain any blank space character except the first blank space after <lun> is needed. # This line must occur at least once. The value of <lun> can be between 0 and 2^14-1 # In fileio mode (default), it defi nes a mapping between a "Logical Unit Number" <lun> and a given device <device> , which # can be any block device (including regular block devices like hdX and sdX and virtual block devices like LVM and Software RAID # devices) or regular files # In blockio mode, it defines a mapping between a "Logical Unit Number" <lun> and a given block device <device>. This mode will # perform direct block i/o with the device, bypassing page-cache for all operations. # Optionally a <scsi_id> can be specified to assign a unique ID to the iSCSI volume. This is useful e.g. in conjunction with a # multipath-aware initiator host accessing the same <device> through several targets. # By default, LUNs are writable, employing write-through caching. By setting IOMode to "ro" a LUN can only be accessed read only. # Setting IOMode to "wb" will enable write-back caching. NOTE: IOMode "wb" is ignored when employing blockio. # In nullio mode, it defines a mapping between a "Logical Unit Number" <lun> and an unnamed virtual device with <size> sectors. # This is ONLY useful for performance measurement purposes. Lun 0 Path=/dev/STORAGE/lun0,Type=fileio ## Optional. The number of connections within a session. Has to be set to "1" (in words: one), which is also the default since MC/S # is not supported. MaxConnections 1 ## Optional. The maximum number of sessions for this target. If this is set to 0 (wich is the default) there is no explicit # session limit. MaxSessions 0 ## Optional. If value is non-zero, the initiator will be "ping"ed during phases of inactivity (i.e. no data transfers) every value # seconds to verify the connection is still alive. If the initiator fails to respond within NOPTimeout seconds, the # connection will be closed. NOPInterval 1 ## Optional. If a non-zero NOPInterval is used to periodically "ping" the initiator during phases of inactivity (i.e. no data # transfers), the initiator must respond within value seconds, otherwise the connection will be closed. If value is set to zero # or if it exceeds NOPInterval , it will be set to NOPInterval. NOPTimeout 5 ## Optional. Has to be set to "Yes" - which is also the default. DataPDUInOrder Yes ## Optional. Has to be set to "Yes" - which is also the default. DataSequenceInOrder Yes
Now we need to define who will have to allow access to ours LUNs, we shall allow to CIDR 192.168.1.0/24
Let's make a backup of the configuration file.
cp /etc/iet/initiators.allow{,.bkp}
Now we shall comment the line ALL ALL that enable access to all LUNs to all clients and let's add a new line enabling the acess to lun0
vim /etc/iet/initiators.allow [...] # ALL ALL iqn.2013-01.br.com.douglasqsantos:storage.lun0 10.101.0.0/24
Now we need to enable the iscsitarget be launched at the boot time, and let's set the ip and port the server will bind.
vim /etc/default/iscsitarget ISCSITARGET_ENABLE=true ISCSITARGET_MAX_SLEEP=3 # ietd options # See ietd(8) for details ISCSITARGET_OPTIONS="--address=192.168.1.100 --port=3260 "
Let's restart the iscsitarget service as follows.
/etc/init.d/iscsitarget restart
Let's show the open session to our LUN as follows
cat /proc/net/iet/session tid:1 name:iqn.2015-04.br.com.douglasqsantos:storage.lun0
Let's check the LUNs that will be exported as follows.
cat /proc/net/iet/volume
tid:1 name:iqn.2013-01.br.com.douglasqsantos:storage.lun0
lun:0 state:0 iotype:fileio iomode:wt blocks:4194304 blocksize:512 path:/dev/STORAGE/lun0
Configuring the Debian Client
Let's update the repositories and upgrade the all system.
aptitude update && aptitude dist-upgrade -y
Let's install the iscsi client as follows
aptitude install open-iscsi -y
Let's make a backup of the client configuration file as follows
cp -Rfa /etc/iscsi/initiatorname.iscsi{,.bkp}
Now let's change the iscsi name of our client.
vim /etc/iscsi/initiatorname.iscsi InitiatorName=iqn.2015-04.br.com.douglasqsantos.client01:88288d9a1b78
Let's restart the iscsi service
/etc/init.d/open-iscsi restart
Now let's try to discovery the LUN on the NAS
iscsiadm -m discovery -t st -p 192.168.1.100 192.168.1.100:3260,1 iqn.2015-04.br.com.douglasqsantos:storage.lun0
As just we got the information as we've wanted let's configure the lun access
Let's enable the automatic conneciton.
iscsiadm -m node iqn.2015-04.br.com.douglasqsantos:storage.lun0 --op=update --name node.startup --value=automatic
Now let's change the autentication type.
iscsiadm -m node iqn.2015-04.br.com.douglasqsantos:storage.lun0 --op=update --name node.session.auth.authmethod --value=CHAP
Now let's change the user that has access privileges
iscsiadm -m node iqn.2015-04.br.com.douglasqsantos:storage.lun0 --op=update --name node.session.auth.username --value=usuario
Now let's change the user password that has access privileges
iscsiadm -m node iqn.2015-04.br.com.douglasqsantos:storage.lun0 --op=update --name node.session.auth.password --value=senha
Now let's log on the server.
iscsiadm -m node iqn.2015-04.br.com.douglasqsantos:storage.lun0 --login Logging in to [iface: default, target: iqn.2015-04.br.com.douglasqsantos:storage.lun0, portal: 192.168.1.100,3260] (multiple) Login to [iface: default, target: iqn.2015-04.br.com.douglasqsantos:storage.lun0, portal: 192.168.1.100,3260] successful
Now we can show the connection with the node
iscsiadm -m node -o show # BEGIN RECORD 2.0-873 node.name = iqn.2015-04.br.com.douglasqsantos:storage.lun0 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.bootproto = <empty> iface.subnet_mask = <empty> iface.gateway = <empty> iface.ipv6_autocfg = <empty> iface.linklocal_autocfg = <empty> iface.router_autocfg = <empty> iface.ipv6_linklocal = <empty> iface.ipv6_router = <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 node.discovery_address = 192.168.1.100 node.discovery_port = 3260 node.discovery_type = send_targets node.session.initial_cmdsn = 0 node.session.initial_login_retry_max = 8 node.session.xmit_thread_priority = -20 node.session.cmds_max = 128 node.session.queue_depth = 32 node.session.nr_sessions = 1 node.session.auth.authmethod = CHAP node.session.auth.username = usuario node.session.auth.password = ******** [...]
Now we can show the session as follow
iscsiadm -m session -o show tcp: [6] 192.168.1.100:3260,1 iqn.2015-04.br.com.douglasqsantos:storage.lun0 (non-flash)
We can show the connection with the host as well
iscsiadm -m host -o show tcp: [10] 192.168.1.102,[<empty>],<empty> <empty>
If you got some problem with the connection and need to remove the host, session or node we can use the follow commands
iscsiadm -m host -o delete iscsiadm -m node -o delete iscsiadm -m session -o delete
Example, we need to logout from the session.
iscsiadm -m node -u Logging out of session [sid: 6, target: iqn.2015-04.br.com.douglasqsantos:storage.lun0, portal: 192.168.1.100,3260] Logout of [sid: 6, target: iqn.2015-04.br.com.douglasqsantos:storage.lun0, portal: 192.168.1.100,3260] successful.
Now we can remove the node.
iscsiadm -m node iqn.2015-04.br.com.douglasqsantos:storage.lun0 -o delete
Now if I try to show the information about the node I'll get the follow message
iscsiadm -m node iqn.2015-04.br.com.douglasqsantos:storage.lun0 -o show iscsiadm: No records found
If you've tested the steps above please log on again in the NAS before to follow the next steps.
Now let's check in the dmesg the new device
dmesg [...] [ 2581.823463] sd 10:0:0:0: [sdb] Attached SCSI disk [ 3127.027900] scsi11 : iSCSI Initiator over TCP/IP [ 3128.041754] scsi 11:0:0:0: Direct-Access IET VIRTUAL-DISK 0 PQ: 0 ANSI: 4 [ 3128.048398] sd 11:0:0:0: Attached scsi generic sg2 type 0 [ 3128.049183] sd 11:0:0:0: [sdb] 14680064 512-byte logical blocks: (7.51 GB/7.00 GiB) [ 3128.050004] sd 11:0:0:0: [sdb] Write Protect is off [ 3128.050012] sd 11:0:0:0: [sdb] Mode Sense: 77 00 00 08 [ 3128.053991] sd 11:0:0:0: [sdb] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA [ 3128.059804] sdb: unknown partition table [ 3128.065097] sd 11:0:0:0: [sdb] Attached SCSI disk
Now we need to create a partition in our new disk as follow
fdisk /dev/sdb
Welcome to fdisk (util-linux 2.25.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Device does not contain a recognized partition table.
Created a new DOS disklabel with disk identifier 0xd7a32fe8.
Command (m for help): n
Partition type
p primary (0 primary, 0 extended, 4 free)
e extended (container for logical partitions)
Select (default p): p
Partition number (1-4, default 1): 1
First sector (2048-14680063, default 2048): #ENTER
Last sector, +sectors or +size{K,M,G,T,P} (2048-14680063, default 14680063): #ENTER
Created a new partition 1 of type 'Linux' and of size 7 GiB.
Command (m for help): w
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.
As I've created the partition with the all amount of space let's create the file system now.
mkfs.ext4 -L ISCSI -m 0 /dev/sdb1
mke2fs 1.42.12 (29-Aug-2014)
Creating filesystem with 1834752 4k blocks and 458752 inodes
Filesystem UUID: d9ccbb02-b64f-480e-b1e8-c4c37df2f568
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632
Allocating group tables: done
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done
Here I've used the option -L to insert a label and -m 0 to not store 5% of disk for root user.
Now let's create a directory to mount the new partition.
mkdir /iscsi
Now let's mount the new partition as follows
mount /dev/sdb1 /iscsi/
Now let's display our partitions
df -Th Filesystem Type Size Used Avail Use% Mounted on /dev/dm-0 ext4 9,3G 1,2G 7,6G 14% / udev devtmpfs 10M 0 10M 0% /dev tmpfs tmpfs 201M 4,5M 196M 3% /run tmpfs tmpfs 501M 0 501M 0% /dev/shm tmpfs tmpfs 5,0M 0 5,0M 0% /run/lock tmpfs tmpfs 501M 0 501M 0% /sys/fs/cgroup /dev/mapper/vg01-var ext4 6,3G 396M 5,6G 7% /var /dev/mapper/vg01-tmp ext4 1,8G 2,9M 1,7G 1% /tmp /dev/sda1 ext4 268M 33M 218M 13% /boot /dev/sdb1 ext4 6,8G 16M 6,4G 1% /iscsi
As we've mounted the partition with no problem, let's put it in the boot time.
echo "/dev/sdb1 /iscsi ext4 _netdev,defaults,noatime 0 0">> /etc/fstab
As the mount is via network we need to use the option _netdev and to tunning the filesystem I used the option noatime to disable the update in the access files.
Now let's update the file with the options about the iscsi
vim /etc/iscsi/iscsid.conf [...] node.startup = automatic [...] node.session.auth.authmethod = CHAP [...] node.session.auth.username = usuario node.session.auth.password = senha [...] node.session.cmds_max = 1024 [...] node.session.queue_depth = 128 [...] node.session.iscsi.FastAbort = No
Now let's restart the client to make sure that everything is ok.
reboot
Now we need to take a look at the uptime of the client and make sure that client has just restarted.
uptime 19:44:11 up 0 min, 1 user, load average: 0,36, 0,11, 0,04
Now let's take a look at the mount points.
df -Th Filesystem Type Size Used Avail Use% Mounted on /dev/dm-0 ext4 9,3G 1,2G 7,6G 14% / udev devtmpfs 10M 0 10M 0% /dev tmpfs tmpfs 201M 4,5M 196M 3% /run tmpfs tmpfs 501M 0 501M 0% /dev/shm tmpfs tmpfs 5,0M 0 5,0M 0% /run/lock tmpfs tmpfs 501M 0 501M 0% /sys/fs/cgroup /dev/sda1 ext4 268M 33M 218M 13% /boot /dev/mapper/vg01-var ext4 6,3G 396M 5,6G 7% /var /dev/mapper/vg01-tmp ext4 1,8G 2,9M 1,7G 1% /tmp /dev/sdb1 ext4 6,8G 16M 6,4G 1% /iscsi
Now let's check the client connection on the server side.
On the NAS Server
cat /proc/net/iet/session
tid:1 name:iqn.2015-04.br.com.douglasqsantos:storage.lun0
sid:3377699741303296 initiator:iqn.2015-04.br.com.douglasqsantos.client01:88288d9a1b78
cid:0 ip:192.168.1.102 state:active hd:none dd:none
Creating a brand new LUN on NAS Server
Now let's create more one logical volume to use as LUN
lvcreate -v -L 7G -n lun1 STORAGE
Now we need to create a new entry for our new LUN
vim /etc/iet/ietd.conf ### LUN 0 ### ## A target definition and the target name. The targets name (the iSCSI Qualified Name ) # must be a globally unique name (as defined by the iSCSI standard) and has to start # with iqn followed by a single dot like this # Target iqn.<yyyy-mm>.<tld.domain.some.host>[:<identifier>] e.g (Target iqn.2004-07.com.example.host:storage.disk2.sys1.xyz) Target iqn.2015-04.br.com.douglasqsantos:storage.lun0 ## This assigns an optional <aliasname> to the target. Alias LUN0 ## The <username> and <password> used to authenticate the iSCSI initiators to this target. # It may be different from the username and password in section GLOBAL OPTIONS, which is # used for discovery IncomingUser usuario senha ## The <username> and <password> used to authenticate this iSCSI target to initiators. # Only one OutgoingUser per target is supported. It may be different from the username # and password in section GLOBAL OPTIONS, which is used for discovery. OutgoingUser ## Lun <lun> Path=<device>,Type=(fileio|blockio)[,ScsiId=<scsi_id>][,ScsiSN=<scsi_sn>][,IOMode=(wb|ro)] | Sectors=<size>,Type=nullio # Parameters after <lun> should not contain any blank space character except the first blank space after <lun> is needed. # This line must occur at least once. The value of <lun> can be between 0 and 2^14-1 # In fileio mode (default), it defi nes a mapping between a "Logical Unit Number" <lun> and a given device <device> , which # can be any block device (including regular block devices like hdX and sdX and virtual block devices like LVM and Software RAID # devices) or regular files # In blockio mode, it defines a mapping between a "Logical Unit Number" <lun> and a given block device <device>. This mode will # perform direct block i/o with the device, bypassing page-cache for all operations. # Optionally a <scsi_id> can be specified to assign a unique ID to the iSCSI volume. This is useful e.g. in conjunction with a # multipath-aware initiator host accessing the same <device> through several targets. # By default, LUNs are writable, employing write-through caching. By setting IOMode to "ro" a LUN can only be accessed read only. # Setting IOMode to "wb" will enable write-back caching. NOTE: IOMode "wb" is ignored when employing blockio. # In nullio mode, it defines a mapping between a "Logical Unit Number" <lun> and an unnamed virtual device with <size> sectors. # This is ONLY useful for performance measurement purposes. Lun 0 Path=/dev/STORAGE/lun0,Type=fileio ## Optional. The number of connections within a session. Has to be set to "1" (in words: one), which is also the default since MC/S # is not supported. MaxConnections 1 ## Optional. The maximum number of sessions for this target. If this is set to 0 (wich is the default) there is no explicit # session limit. MaxSessions 0 ## Optional. If value is non-zero, the initiator will be "ping"ed during phases of inactivity (i.e. no data transfers) every value # seconds to verify the connection is still alive. If the initiator fails to respond within NOPTimeout seconds, the # connection will be closed. NOPInterval 1 ## Optional. If a non-zero NOPInterval is used to periodically "ping" the initiator during phases of inactivity (i.e. no data # transfers), the initiator must respond within value seconds, otherwise the connection will be closed. If value is set to zero # or if it exceeds NOPInterval , it will be set to NOPInterval. NOPTimeout 5 ## Optional. Has to be set to "Yes" - which is also the default. DataPDUInOrder Yes ## Optional. Has to be set to "Yes" - which is also the default. DataSequenceInOrder Yes ### LUN 1 ### ## A target definition and the target name. The targets name (the iSCSI Qualified Name ) # must be a globally unique name (as defined by the iSCSI standard) and has to start # with iqn followed by a single dot like this # Target iqn.<yyyy-mm>.<tld.domain.some.host>[:<identifier>] e.g (Target iqn.2004-07.com.example.host:storage.disk2.sys1.xyz) Target iqn.2015-04.br.com.douglasqsantos:storage.lun1 ## This assigns an optional <aliasname> to the target. Alias LUN1 ## The <username> and <password> used to authenticate the iSCSI initiators to this target. # It may be different from the username and password in section GLOBAL OPTIONS, which is # used for discovery IncomingUser usuario senha ## The <username> and <password> used to authenticate this iSCSI target to initiators. # Only one OutgoingUser per target is supported. It may be different from the username # and password in section GLOBAL OPTIONS, which is used for discovery. OutgoingUser ## Lun <lun> Path=<device>,Type=(fileio|blockio)[,ScsiId=<scsi_id>][,ScsiSN=<scsi_sn>][,IOMode=(wb|ro)] | Sectors=<size>,Type=nullio # Parameters after <lun> should not contain any blank space character except the first blank space after <lun> is needed. # This line must occur at least once. The value of <lun> can be between 0 and 2^14-1 # In fileio mode (default), it defi nes a mapping between a "Logical Unit Number" <lun> and a given device <device> , which # can be any block device (including regular block devices like hdX and sdX and virtual block devices like LVM and Software RAID # devices) or regular files # In blockio mode, it defines a mapping between a "Logical Unit Number" <lun> and a given block device <device>. This mode will # perform direct block i/o with the device, bypassing page-cache for all operations. # Optionally a <scsi_id> can be specified to assign a unique ID to the iSCSI volume. This is useful e.g. in conjunction with a # multipath-aware initiator host accessing the same <device> through several targets. # By default, LUNs are writable, employing write-through caching. By setting IOMode to "ro" a LUN can only be accessed read only. # Setting IOMode to "wb" will enable write-back caching. NOTE: IOMode "wb" is ignored when employing blockio. # In nullio mode, it defines a mapping between a "Logical Unit Number" <lun> and an unnamed virtual device with <size> sectors. # This is ONLY useful for performance measurement purposes. Lun 0 Path=/dev/STORAGE/lun1,Type=fileio ## Optional. The number of connections within a session. Has to be set to "1" (in words: one), which is also the default since MC/S # is not supported. MaxConnections 1 ## Optional. The maximum number of sessions for this target. If this is set to 0 (wich is the default) there is no explicit # session limit. MaxSessions 0 ## Optional. If value is non-zero, the initiator will be "ping"ed during phases of inactivity (i.e. no data transfers) every value # seconds to verify the connection is still alive. If the initiator fails to respond within NOPTimeout seconds, the # connection will be closed. NOPInterval 1 ## Optional. If a non-zero NOPInterval is used to periodically "ping" the initiator during phases of inactivity (i.e. no data # transfers), the initiator must respond within value seconds, otherwise the connection will be closed. If value is set to zero # or if it exceeds NOPInterval , it will be set to NOPInterval. NOPTimeout 5 ## Optional. Has to be set to "Yes" - which is also the default. DataPDUInOrder Yes ## Optional. Has to be set to "Yes" - which is also the default. DataSequenceInOrder Yes
Now we need to give the allow access to 192.168.1.0/24
vim /etc/iet/initiators.allow [...] iqn.2015-04.br.com.douglasqsantos:storage.lun0 192.168.1.0/24 iqn.2015-04.br.com.douglasqsantos:storage.lun1 192.168.1.0/24
Now let's restart the iscsi server
/etc/init.d/iscsitarget restart
Now let's display the volumes
cat /proc/net/iet/volume
tid:2 name:iqn.2015-04.br.com.douglasqsantos:storage.lun1
lun:0 state:0 iotype:fileio iomode:wt blocks:14680064 blocksize:512 path:/dev/STORAGE/lun1
tid:1 name:iqn.2015-04.br.com.douglasqsantos:storage.lun0
lun:0 state:0 iotype:fileio iomode:wt blocks:14680064 blocksize:512 path:/dev/STORAGE/lun0
Cliente CentOS
Use the following script to make sure that your system has all the packets and configuration to use this how-to http://wiki.douglasqsantos.com.br/doku.php/confinicialcentos6_en
Let's update the repositories and update the system with the newest packets
yum check-update && yum update -y
Now we need to install the packets to able the CentOS to work with the iscsi
yum install iscsi-initiator-utils iscsi-initiator-utils-devel -y
Now we need to put the iscsi in the boot time.
chkconfig --add iscsi chkconfig --add iscsid
After put the iscsi in the boot time we need to enable it.
chkconfig iscsi on chkconfig iscsid on
Now let's restart the service to be able to work with it.
/etc/init.d/iscsi restart
Let's check out what are the LUNs available to us on the NAS server
iscsiadm -m discovery -t st -p 10.101.0.25 10.101.0.25:3260,1 iqn.2013-01.br.com.douglasqsantos:storage.lun1 10.101.0.25:3260,1 iqn.2013-01.br.com.douglasqsantos:storage.lun0
As we can see we have two LUNs available to connect to, but we need to use only the one that are created to us.
We need to get our iqn of the CentOS client.
cat /etc/iscsi/initiatorname.iscsi InitiatorName=iqn.1994-05.com.redhat:4a84d448b327
Now that we have the iqn that is the iscsi id for the client we need to enable only the CentOs client to connect in it.
On the NAS Server.
vim /etc/iet/initiators.allow [...] iqn.2013-01.br.com.douglasqsantos:storage.lun0 10.101.0.0/24 iqn.2013-01.br.com.douglasqsantos:storage.lun1 iqn.1994-05.com.redhat:4a84d448b327
As we can see has a issue the lun0 still will show to the CentOS client, but the lun1 won't be show to the Debian Client so let's restart the iscsitarget.
/etc/init.d/iscsitarget restart
On the Debian Client let's check the iscsi connections available.
iscsiadm -m discovery -t st -p 10.101.0.25 10.101.0.25:3260,1 iqn.2013-01.br.com.douglasqsantos:storage.lun0
As we can see only one LUN was showed because we've created a rule to enable only the CentOS client to see the other one.
On the CentOS client we can see the both LUNs connections.
iscsiadm -m discovery -t st -p 10.101.0.25 10.101.0.25:3260,1 iqn.2013-01.br.com.douglasqsantos:storage.lun0 10.101.0.25:3260,1 iqn.2013-01.br.com.douglasqsantos:storage.lun1
Let's get the iqn of the Debian Client.
tail -n 1 /etc/iscsi/initiatorname.iscsi InitiatorName=iqn.1993-08.org.debian:01:51fe411a118d
Now let's created another rule to match with the iqn of the Debian Client and enable only this iqn to has access to the lun0.
On the Nas Server.
vim /etc/iet/initiators.allow [...] iqn.2013-01.br.com.douglasqsantos:storage.lun0 iqn.1993-08.org.debian:01:51fe411a118d iqn.2013-01.br.com.douglasqsantos:storage.lun1 iqn.1994-05.com.redhat:4a84d448b327
Let's restart the iscsitarget.
/etc/init.d/iscsitarget restart
On the CentOS client let's show the LUNs again.
iscsiadm -m discovery -t st -p 10.101.0.25 10.101.0.25:3260,1 iqn.2013-01.br.com.douglasqsantos:storage.lun1
If you get some errors as bellow.
iscsiadm -m discovery -t st -p 10.101.0.25 iscsiadm: This command will remove the record [iface: default, target: iqn.2013-01.br.com.douglasqsantos:storage.lun0, portal: 10.101.0.25,3260], but a session is using it. Logout session then rerun command to remove record. 10.101.0.25:3260,1 iqn.2013-01.br.com.douglasqsantos:storage.lun1
We need to do the logout.
iscsiadm -m node -u
Now we can control the LUNs
Now as we don't need to login with an user and password on the lun1 we can connect as following.
iscsiadm -m node -l -T iqn.2013-01.br.com.douglasqsantos:storage.lun1 -p 10.101.0.25:3260 Logging in to [iface: default, target: iqn.2013-01.br.com.douglasqsantos:storage.lun1, portal: 10.101.0.25,3260] (multiple) Login to [iface: default, target: iqn.2013-01.br.com.douglasqsantos:storage.lun1, portal: 10.101.0.25,3260] successful.
We can check the session with the NAS Server.
iscsiadm -m session -P 2
Target: iqn.2013-01.br.com.douglasqsantos:storage.lun1
Current Portal: 10.101.0.25:3260,1
Persistent Portal: 10.101.0.25:3260,1
**********
Interface:
**********
Iface Name: default
Iface Transport: tcp
Iface Initiatorname: iqn.1994-05.com.redhat:bf9c07079f6
Iface IPaddress: 10.101.0.50
Iface HWaddress: <empty>
Iface Netdev: <empty>
SID: 1
iSCSI Connection State: LOGGED IN
iSCSI Session State: LOGGED_IN
Internal iscsid Session State: NO CHANGE
*********
Timeouts:
*********
Recovery Timeout: 120
Target Reset Timeout: 30
LUN Reset Timeout: 30
Abort Timeout: 15
*****
CHAP:
*****
username: <empty>
password: ********
username_in: <empty>
password_in: ********
************************
Negotiated iSCSI params:
************************
HeaderDigest: None
DataDigest: None
MaxRecvDataSegmentLength: 262144
MaxXmitDataSegmentLength: 8192
FirstBurstLength: 65536
MaxBurstLength: 262144
ImmediateData: Yes
InitialR2T: Yes
MaxOutstandingR2T: 1
As we can see there is a conneciton on the state of LOGGED IN
We can see the new device on the dmesg
scsi7 : iSCSI Initiator over TCP/IP scsi 7:0:0:1: Direct-Access IET VIRTUAL-DISK 0 PQ: 0 ANSI: 4 sd 7:0:0:1: Attached scsi generic sg2 type 0 sd 7:0:0:1: [sdc] 4194304 512-byte logical blocks: (7.51 GB/7.00 GiB) sd 7:0:0:1: [sdc] Write Protect is off sd 7:0:0:1: [sdc] Mode Sense: 77 00 00 08 sd 7:0:0:1: [sdc] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA sdc: unknown partition table sd 7:0:0:1: [sdc] Attached SCSI disk
As we can see now theis is a devices called sdc via iscsi, so let's check the partition table.
fdisk /dev/sdc
WARNING: DOS-compatible mode is deprecated. It's strongly recommended to
switch off the mode (command 'c') and change display units to
sectors (command 'u').
Comando (m para ajuda): n
Comando - ação
e estendida
p partição primária (1-4)
p
Número da partição (1-4): 1
Primeiro cilindro (1-1020, default 1): #ENTER
Using default value 1
Last cilindro, +cilindros or +size{K,M,G} (1-1020, default 1020): #ENTER
Using default value 1020
Comando (m para ajuda): w
A tabela de partições foi alterada!
Chamando ioctl() para reler tabela de partições.
Sincronizando discos.
Above I've created a partition with the whole space of the disk, so we need to create a filesystem that will able us to use the partition.
mkfs.ext4 -L ISCSI -m 0 /dev/sdc1
mke2fs 1.41.12 (17-May-2010)
Filesystem label=ISCSI
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
458752 inodes, 1833952 blocks
0 blocks (0.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=1879048192
56 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, 1605632
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done
This filesystem will be automatically checked every 28 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
Was used the label -L to set up the label of the partition and the -m 0 to do not reserve the 5% of the disk space for the root user.
Now let's create a new directory to mount the partition
mkdir /iscsi
Now let's mount the new partition on /iscsi
mount /dev/sdc1 /iscsi/
Now let's list the partitions mounted.
df Sist. Arq. Tipo Size Used Avail Use% Montado em /dev/sda5 ext4 47G 7,8G 37G 18% / tmpfs tmpfs 3,9G 5,3M 3,9G 1% /dev/shm /dev/sda1 ext4 461M 81M 357M 19% /boot /dev/sda7 ext4 410G 232G 157G 60% /home /dev/sdb1 ext4 294G 191M 279G 1% /srv /dev/sdc1 ext4 6,9G 144M 6,8G 3% /iscsi
As everything is ok, let's add the new partition on the boot time.
echo "/dev/sdc1 /iscsi ext4 _netdev,defaults,noatime 0 0">> /etc/fstab
As the the new partition use the network to mount we need to use the flag _netdev and to add more efficiency to the I/O was disabled the updated of the access file.
Now let's update the iscsi client configuration.
vim /etc/iscsi/iscsid.conf [...] node.startup = automatic [...] node.session.cmds_max = 1024 [...] node.session.queue_depth = 128 [...] node.session.iscsi.FastAbort = No
Let's restart the client and make sure that everything is working properly
reboot
Let's check the uptime of the client.
uptime 15:26:35 up 0 min, 1 user, load average: 0.00, 0.00, 0.00
Let's list the partition table.
df Sist. Arq. Tipo Size Used Avail Use% Montado em /dev/sda5 ext4 47G 7,8G 37G 18% / tmpfs tmpfs 3,9G 5,3M 3,9G 1% /dev/shm /dev/sda1 ext4 461M 81M 357M 19% /boot /dev/sda7 ext4 410G 232G 157G 60% /home /dev/sdb1 ext4 294G 191M 279G 1% /srv /dev/sdc1 ext4 6,9G 144M 6,8G 3% /iscsi
Now let's see the connection with the NAS server.
On the NAS server.
cat /proc/net/iet/session
tid:2 name:iqn.2013-01.br.com.douglasqsantos:storage.lun1
sid:562949990973952 initiator:iqn.1994-05.com.redhat:43c7a0d2ad63
cid:0 ip:10.101.0.1 state:active hd:none dd:none
tid:1 name:iqn.2013-01.br.com.douglasqsantos:storage.lun0
sid:281474997486080 initiator:iqn.1993-08.org.debian:01:fa98a8565dfe
cid:0 ip:10.101.0.26 state:active hd:none dd:none
Let's check the volumes
cat /proc/net/iet/volume
tid:2 name:iqn.2013-01.br.com.douglasqsantos:storage.lun1
lun:1 state:0 iotype:fileio iomode:wt blocks:4194304 blocksize:512 path:/dev/STORAGE/lun1
tid:1 name:iqn.2013-01.br.com.douglasqsantos:storage.lun0
lun:0 state:0 iotype:fileio iomode:wt blocks:4194304 blocksize:512 path:/dev/STORAGE/lun0
If you need add more LUNs it's only to create another LV and add the entries into /etc/iet/ietd.conf was we did with the other ones.