Cisco Video Management and Storage System 1.0 CLI Administrator Guide
Configuring iSCSI Devices

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 
                                   Sessn
  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 
                                  Sessn
  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 
       Rec Log
  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 
       Rec Log
  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!!!
!!!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!!!
!!!WARNING!!!  If you are not sure what to do, answer "no" to the
!!!WARNING!!!  following question and then exit.
!!!WARNING!!!

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)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
366247936 inodes, 732481536 blocks
36624076 blocks (5.00%) reserved for the super user
First data block=0
22354 block groups
32768 blocks per group, 32768 fragments per group
16384 inodes 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