Table Of Contents
Configuring iSCSI Devices
Configure Only One VSMS to Same iSCSI Target
Configuring iSCSI Storage Devices
Prerequisites and Considerations
Examples
Formatting iSCSI Storage Devices
Examples
Configuring iSCSI Devices
Last Update: March 7, 2008
This section describes how to configure the Cisco Video Management and Storage iSCSI (Internet small computer system interface) storage devices. Use the Cisco Video Management and Storage command-line interface (CLI) commands to add a new iSCSI devices or to modify existing iSCSI devices.
When configuring an external iSCSI interface, use the external Gigabit Ethernet connector located on the Cisco Video Management and Storage module to connect to external iSCSI mass storage devices. Currently, only ext3 file systems are supported. For more information on configuring ext3 file systems, see the SATABOY: Nexsan Technologies Product Manual.
Configure Only One VSMS to Same iSCSI Target
The iSCSI protocol is an Internet-enabled SCSI protocol and acts like the SCSI protocol, in which only one Video Surveillance Management System (VSMS) can access one iSCSI disk drive. You must avoid connecting more than one VSMS to the same iSCSI target. Traditional file systems, such as ext3, are designed to work on only one VSMS at a time.
Caution 
Mounting a file system on more than one VSMS at a time will almost certainly cause problems with unpredictable results.
Be aware that even when ext3 is mounted in read-only mode, ext3 might still write to the disk drive. It might not write data but will replay the journal. If another VSMS has already been mounted on the same file system, data will almost certainly be corrupted.
Configuring iSCSI Storage Devices
Use the storages iscsi commands to configure iSCSI storage devices managed by the Cisco Video Management and Storage module.
Prerequisites and Considerations
Before configuring iSCSI storage devices, be aware of the following prerequisites and considerations:
1.
The iSCSI CLI commands allow you to configure nine media tags (media1, media2, and so on to media9) to support up to nine unique iSCSI targets. The mount point /media0 is assigned to the Cisco Video Management and Storage module local hard disk repository.
2.
Each media profile must be assigned a unique IP address.
3.
Each target is allowed to have up to 16 volumes (also called LUNs) of major raw devices.
4.
Devices can be formatted by using the CLI. The iSCSI devices can be formatted only to ext3 format.
Caution 
Direct access to the storage device, for example /dev/sda, is not allowed with an iSCSI device. You must use the media tag that you defined in the configuration of the iSCSI target tag. Formatting of the storage device is denied if the device is occupied or busy. However, once it is cleared of the busy condition, a storage device can be formatted regardless of its existing format—valid, invalid, supported, unsupported, or unknown FS type. The formatting of multiple devices at the same time is not supported.
5.
Each volume is translated into logical unit number (LUN) numbering from initiator aspect, typically 0, 1, 2, and so on.
6.
A mountable directory is named using a tag name with the LUN number suffix. For example, a target tag of /media1 with single volume number 0 is named as /media1_0; that is, the mount point is followed by an underscore (_) character and the volume number 0.
7.
Multiple iSCSI-based storage devices can be attached to any Cisco Video Management and Storage System module. Likewise, multiple Cisco Video Management and Storage System modules can access the same iSCSI target. Multiple modules accessing the same iSCSI target must be avoided at the administration level because, at the CLI level, there are no commands for checking multiple configurations to prevent such configurations.
8.
Authentication is not necessary because the Cisco Video Management and Storage System uses a dedicated private VLAN through either the secured internal or secured external Gigabyte Ethernet interface.
9.
Administrators manage the iSCSI targets and volumes of each target allocation to ensure that no multiple VSMS access is configured to a single target or target volume (see the "Configure Only One VSMS to Same iSCSI Target" section).
10.
Any devices of unsupported file system types (for example, ext2) are recorded and logged in, but their use is disabled because they are not mounted.
11.
If target storage servers are reloaded or power cycled, the iSCSI tags must be logged in again because, after the target iSCSI device is powered cycled or reloaded, existing sessions and sequence numbers are reset. Rediscovery and relogin are necessary after the target storage device is operational.
12.
The external Gigabit Ethernet connector located on the Cisco Video Management and Storage module is used to connect to iSCSI mass storage devices.
SUMMARY STEPS
1.
configure terminal
2.
storages iscsi media1-media9
3.
[default | description | login | state | target-ip]
4.
end
5.
exit
6.
show storages iscsi filesystem
or
show storages all filesystem
or
show storages iscsi configuration summary
or
show storages iscsi configuration detail
DETAILED STEPS
|
Command or Action
|
Purpose
|
Step 1
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 2
|
storages iscsi media1-media9
Example:
cvmss-module(config)> storages iscsi
media1
Adding new iscsi
cvmss-module(config-iscsi)>
|
Enters iSCSI configuration mode.
media1-media9: String identifier for the IP iSCSI mass storage device in the range of media1 to media9.
|
Step 3
|
[default | description | login | state |
target-ip | timeout-node-session]
Example:
cvmss-module(config-iscsi)> storages
iscsi media1
Adding new iscsi
cvmss-module(config-iscsi)> default
cvmss-module(config-iscsi)> target-ip
172.19.156.43
cvmss-module(config-iscsi)>
timeout-node-session 180
cvmss-module(config-iscsi)> login
disabled
cvmss-module(config-iscsi)>
descripton"media1: southwest branch"
cvmss-module(config-iscsi)> state enabled
cvmss-module(config-iscsi)> end
cvmss-module(config)> exit
cvmss-module>
Example: With DNS Configured
cvmss-module(config)> ip name-server
172.70.168.183 171.68.226.120
cvmss-module(config-iscsi)> storages
iscsi media2
Adding new iscsi
cvmss-module(config-iscsi)> default
cvmss-module(config-iscsi)> target-ip
www.sanjose_downtown.org
|
Configures iSCSI storage target device configuration parameters.
default: iSCSI storage target device default value.
description: iSCSI storage target device description text in quotes. Up to 80 text characters are allowed. Default: " "
login: Enables or disables iSCSI storage target device login.
• disabled: disables iSCSI storage target device login
• enabled: enables iSCSI storage target device login
Default: enabled.
state: Enables or disables the operational state of the iSCSI storage target device:
• disabled: disables the operational state of the iSCSI storage target device.
• enabled: enables the operational state of the iSCSI storage target device.
Default: enabled.
target-ip: Sets the iSCSI storage target IP address in dotted decimal format or hostname.
Note If you need to use a hostname, make sure that you have DNS configured (see example).
timeout-node-session: Sets the node session timeout waiting period in the range from 0 to 32767 seconds before reestablishing node sessions.
Default: 120 seconds.
|
Step 4
|
end
Example:
cvmss-module(config-iscsi)> end
cvmss-module(config)>
|
Exits the storage iSCSI configuration mode.
|
Step 5
|
exit
Example:
cvmss-module(config)> exit
cvmss-module>
|
Exits global configuration mode.
|
Step 6
|
show storages iscsi filesystem
or
show storages all filesystem
show storages iscsi configuration summary
or
show storages iscsi configuration detail
Example:
cvmss-module> show storages iscsi
filesystem
or
cvmss-module> show storages all
filesystem
or
cvmss-module> show storages iscsi
configuration summary
or
cvmss-module> show storages iscsi
configuration detail
|
Displays a summary of iSCSI storage device by iSCSI or all file systems, general summary of all device configurations, or detailed summary of all device configurations.
|
Examples
To view a summary of file systems, use the show storages iscsi filesystem command. For example:
cvmss-module# show storages iscsi filesystem
Filesystem 1K-blocks Used Available Use% Mounted on
==================== =========== ======= ========== ==== ==========
/dev/sdb 2307162084 1171905380 1018059636 54% /media1_0
/dev/sdc 576789800 106560 547384004 1% /media1_1
To view all the configured file systems, use the show storages all filesystem command. For example:
cvmss-module# show storages all filesystem
Filesystem 1K-blocks Used Available Use% Mounted on
==================== =========== ======= ========== ==== ==========
rootfs 9775184 1081472 8693712 12% /
/dev/root 9775184 1081472 8693712 12% /
none 1036520 0 1036520 0% /dev/shm
/dev/sda3 142284500 32828 135024032 1% /media0
/dev/sdb 2307162084 1171912476 1018052540 54% /media1_0
/dev/sdc 576789800 106560 547384004 1% /media1_1
To view a general summary of iSCSI storage device configurations, use the show storages iscsi configuration summary command. For example:
cvmss-module# show storages iscsi configuration summary
Tag Login State Target IP Timeo
====== ===== ===== =============== =====
media1 yes on 192.168.1.254 120
To view a detailed summary of iSCSI storage device configurations, use the show storages iscsi configuration detail command. For example:
cvmss-module# show storages iscsi configuration detail
Tag Login State Target IP Timeo Username Passowrd
====== ===== ===== =============== ===== ======== ========
media1 yes on 192.168.1.254 120 <none> <none>
You can also display the general or detailed status of the iSCSI storage device configurations.
To view a general status of the configured iSCSI storage devices, use the show storages iscsi status summary command. For example:
cvmss-module# show storages iscsi status summary
Tag ord in Device Mounts LUN Vol FS Types iSCSI Portal IO
====== === === ======== =========== === === ======== ====================== ==
media1 yes yes /dev/sdb /media1_0 0 2 ext3 192.168.1.254:3260,1 rw
media1 yes yes /dev/sdc /media1_1 1 2 ext3 192.168.1.254:3260,1 rw
To view a detailed status of the configured iSCSI storage devices, use the show storages iscsi status detail command. For example:
cvmss-module# show storages iscsi status detail
Tag ord in Device Mounts LUN Vol FS Types iSCSI Portal IO Target Name
====== === === ======== =========== === === ======== ====================== == ===========
media1 yes yes /dev/sdb /media1_0 0 2 ext3 192.168.1.254:3260,1 rw
iqn.1999-02.com.nexsan:p0:sataboy:01731a5a
media1 yes yes /dev/sdc /media1_1 1 2 ext3 192.168.1.254:3260,1 rw
iqn.1999-02.com.nexsan:p0:sataboy:01731a5a
Formatting iSCSI Storage Devices
You must take the highest level of caution when using the CLI to format iSCSI storage devices. You cannot directly access the storage device (for example, /dev/sda) with an iSCSI device. You must use the media tag that you defined in the configuration of the iSCSI target tag. If the device is occupied or busy, it cannot be formatted. However, once the device is cleared of the busy condition, a storage device can be formatted regardless of its existing format—valid, invalid, supported, unsupported, or unknown FS type. The formatting of multiple devices at the same time is not supported.
Use the format storages command to format iSCSI mass storage devices managed by the Cisco Video Management and Storage module.
SUMMARY STEPS
1.
format storages storage-type media-tag lun# fs-type
DETAILED STEPS
|
Command or Action
|
Purpose
|
Step 1
|
format storages storage-type media-tag
lun# fs-type
Example:
cvmss-module# format storages iscsi
media8 0 ext3
|
Formats iSCSI storage devices:
storage-type: Sets the storage interface type to iSCSI, USB, or SATA.
Note Only iSCSI is currently supported.
media-tag: Sets the unique string identifier for the IP iSCSI mass storage device in the range of media1 to media9.
lun#: Sets the corresponding iSCSI volume number.
fs-type: Sets the file system type, ext3 or reiserfs.
Note The exdt3 file system is the only type currently supported.
|
Examples
The following example shows the format command for formatting iSCSI mass storage device media8, logical unit number (LUN) 0, and file type ext3. Note the warning message and two confirmations that you must respond to before an attempt is made to format the device.
cvmss-module# format storages iscsi media8 0 ext3
!!!WARNING!!! You are about to start a destructive sequence of
!!!WARNING!!! operations. All data on the storage device will be lost
!!!WARNING!!! and unrecoverable. Depending on the capacity of the
!!!WARNING!!! storage device, the formatting can take up to a few
!!!WARNING!!! hours. During formatting, your console is locked and
!!!WARNING!!! unavailable for use. Before you proceed further, back
!!!WARNING!!! up the contents of the storage device.
!!!WARNING!!! If you are not sure what to do, answer "no" to the
!!!WARNING!!! following question and then exit.
Do you wish to proceed [y/n]? : y
Are you sure you want to format the device and lose all the data [y/n]? : y
Formatting /dev/sdb in ext3
mke2fs 1.37 (21-Mar-2005)
Fragment size=4096 (log=2)
366247936 inodes, 732481536 blocks
36624076 blocks (5.00%) reserved for the super user
32768 blocks per group, 32768 fragments per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624, 11239424, 20480000, 23887872, 71663616, 78675968,
102400000, 214990848, 512000000, 550731776, 644972544
Writing inode tables: 254/22354