| StorageTek SL150 Modular Tape Library User's Guide Revision 6 E24606-06 |
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| StorageTek SL150 Modular Tape Library User's Guide Revision 6 E24606-06 |
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This chapter provides an overview of the major hardware components of Oracle's StorageTek SL150 Tape Library. The library combines the well-known strong suits of automated tape storage with low initial cost and industry-leading scalability. Tape provides economical data consolidation and reliable data protection and retention. Modular design—base unit plus optional expansion modules—and industry standard, 483-mm (19-in) rack mounting provide growth potential. You can expand the capacity of the library as your data grows.
This section introduces basic concepts that underlie the design and functionality of the SL150 library. These include:
The SL150 Modular Tape Library is designed to operate automatically, under the control of a host-resident, storage-, archive-, or backup-management application, such as Oracle Secure Backup. Under normal circumstances, the SL150 library requires little or no operator intervention. Library robotics handle all cartridge movement within the library under application control. Host-application storage catalogs remain consistent and seldom require physical audits of the library contents.
Controlling access to library interfaces and controls is critical to the integrity of stored data and to the efficient administration of library resources. Restricting access to user interfaces that move or modify storage media protects data from inadvertent damage and unauthorized access. But restricting user access excessively may also impede necessary library management, maintenance, and troubleshooting. To manage these conflicting demands efficiently, the SL150 user interfaces implement Role-Based Access Control (RBAC).
RBAC designs limit the use of controls and interfaces to users that have predefined job roles. An administrator creates individual user accounts for each person that needs access to the system. Each account has its own, uniquely identifiable log-in name and personal password. The administrator then assigns each account to a distinct role.
The RBAC approach makes it easy to consistently manage access privileges: you assign privileges to the job function and everyone who performs that function automatically has what they need. But it also makes managing individual usage no less easy: every user retains an individual log-in account that can be monitored and audited.
The SL150 recognizes the following user roles:
The Viewer role has view-only access to the library and access to the mailslot. Viewers can log in, monitor library operations, and view component states and properties. They can also use the mailslot. But they cannot otherwise change the configuration or operations of the library.
The Viewer role should be the norm for most users, and the local operator panel is permanently assigned to it. Since libraries generally operate automatically, under the control of a host-side backup, storage-management, or library-management application, user intervention via the browser-based user interface is not normally required. Checking for problems and gathering routine information are the only tasks that are required under normal conditions.
The Operator role has limited control over the operation of the library, but no control over its configuration.
Under normal circumstances, operators will spend most of their time monitoring the library for problems using the Library Management Screen, Drives Management Screen, and Tapes Management Screen. A storage- or backup-management software application running on the library host controls most routine operations, including movement and mounting of data cartridges, auditing, and, in most cases, drive cleaning.
When necessary, however, operators can perform the following tasks locally, using the SL150 browser-based user interface:
The Service role has all of the capabilities of the Administrator role, except for user administration. When you require the assistance of an Oracle service representative, you create a log-in account for the service person and assign the account to the Service user. This gives the service representative all required access to the system, while keeping your Administrator accounts secure and access to your library under your control.
The SL150 library Administrator has the authority to fundamentally alter the configuration and operation of the library. Administrator tasks include:
granting and denying user access to the library
assigning job roles
setting and/or changing basic library properties, including system time and host connectivity
administering the TCP/IP connection between the library and the Browser-Based User Interface.
administering Simple Network Management Protocol (SNMP)
Given the scope of an administrator's responsibilities, the knowledge required, and the potential for problems if administrative capabilities are misused, you generally want to limit the number of people who are assigned to the Administrator role.
The SL150 tape storage library communicates with the host via a single, unified, control/data path. The host application sends instructions that position robotics, mount and unmount volumes, clean drives, and query the status of components over the same interface used for sending and receiving stored data.
Both data and commands are sent to the Serial Attached SCSI (SAS) or Fibre Channel data interface on a designated Linear Tape Open (LTO) bridged drive. The bridged drive then handles all communications for the library or library partition. Command and control signals are sent to LUN1 (Logical Unit Number 1) of the bridged drive, which is configured as a SCSI medium changer device. The SCSI medium changer communicates with the SL150 library controller across the Automation Device Interface (ADI) on the bridged drive. Data are sent to the remaining LUN on the bridged drive or to LUNs on the other, unbridged drives in the partition, all of which are configured as SCSI sequential-access (tape) devices. A default bridged drive is automatically assigned during library and partition configuration.
Currently, the SL150 library supports Oracle-supplied, half-height, Hewlett-Packard LTO-5 tape drives with SAS or Fibre Channel interfaces and Hewlett-Packard LTO-6 drives with SAS interfaces only.
Generally, storage-applications require exclusive control of their storage media, so that applications do not move or overwrite data that they do not own. If you need to attach more than one host to a library, you must therefore partition the library. Each library partition functions as an independent, logical library dedicated exclusively to its assigned host.
The SL150 library can be automatically partitioned to support two host applications. So, for example, you can assign one half of the storage slots and drives to the system that hosts your backup application and the other to the system that hosts your hierarchical content-management software.
When the partitioning feature is enabled, each hosted application controls one half of the storage cells and one half of the drives in the SL150 library. Partition 1 controls the storage slots on the left side and any drives installed in the top drive bays of the library modules. Partition 2 controls the storage slots on the right side and any drives installed in the bottom drive bays. Note that you can have varying numbers of drives in your partitions as long as each partition contains at least one bridged drive for communication with the host.
When partitioning is enabled, the partitions share a common robot and mailslot while keeping their respective media separate. Whenever a shared resource handles media assigned to a partition, the corresponding partition host has exclusive control over the resource.
The basic user interface to the library is a web application that can be accessed from any workstation that has a network connection and an installed web browser. There is nothing that has to be separately downloaded, locally installed, or locally managed. The Browser-based User Interface is described in detail, below.
The StorageTek SL150 Modular Tape Library is designed for straightforward maintenance and servicing.
Users can, in most cases, troubleshoot and repair their equipment without assistance. Library components are organized into a limited number of Customer Replaceable Units (CRUs), each of which has a discrete function in the library. Faults are automatically isolated within the confines of the unit. If any part fails, the whole fails, and the user simply replaces the entire CRU with an equivalent unit.
CRUs can be installed and removed in a few simple steps, using simple hand tools. In the SL150 library, CRUs are secured to the chassis with captive thumb screws and thumb latches that can be removed and installed using, at most, a Phillips screw driver.
More routine tasks have also been streamlined. Tapes can be rapidly bulk loaded and unloaded to facilitate capacity upgrades, reconfiguration, vaulting, or any other operation that cannot be efficiently managed using the mailslot. Each SL150 library module stores cartridges in two, 15-cell, detachable magazines that you can unlatch and draw out of the front of the module, like a drawer.
An SL150 library consists of Modular Hardware with a Touch-Screen Local Operator Panel and a Browser-based User Interface that library operators and administrators access over your network.
A typical SL150 installation contains a base module and optional expansion modules installed under the base unit. Base and expansion modules share the same storage layout: one or two rear-mounted drives installed one above the other on the center line of the chassis and two drawer-style, front-loading tape magazines at the front, on either side of the chassis. The space between the magazines is reserved for robotic library operations.
Above the magazines, the taller, base module houses the library controller, robotics unit, and mailslot (cartridge access port). The front panel holds the local operator controls. A large, touchscreen operator panel resides in the center, with status LEDs for the touch panel to its left.
The power button, status LEDs for the library, and the library locator LED lie to the upper left of the operator panel.
The rear of the base module holds the cabling and provides service access to drives and power supplies.
The upper right corner of the rear panel (when facing the rear of the base module), holds two, Ethernet, NET MGT ports and nine MODULE OUTPUT ports for the module interconnect cables.
The upper NET MGT port, 0 (Port 1 on the browser-based user interface), supports browser-based user interface connections via the local area network (LAN). It is fully configurable. The lower NET MGT port, 1 (Port 2 on the browser-based user interface), is a service port on a private network local to the library. The service port can be enabled or disabled but cannot be reconfigured.
One or, optionally, two hot-swappable power supplies reside under the cabling ports in the lower right corner of the rear panel. One or two half-height LTO drives are installed to the left of the power supplies on the center line of the chassis. Both drives and power supplies have their own status LEDs. Status LEDs for the library and robotics are visible at center top.
The rear of the expansion module holds provides service access to the module controller at upper right, the drives in the middle, and the power supplies at lower right. The module controller holds the MODULE INPUT port for the module interconnect cable and the status LEDs for the module.
Customer Replaceable Units are secured to the rear of base and expansion modules using easily removable fasteners. The robot/library controller, tape drives, and power supplies are attached by green, captive thumbscrews that can be loosened with a common Phillips screw driver and tightened by hand. The expansion module controller is secured by a latch and lever that can be operated without tools.
The SL150 library user interface is your main tool for configuring, monitoring, and troubleshooting the library. It combines comprehensive library management, monitoring, and security features with ease of access and deployment. The user interface is a web application, so there is nothing to install or administer on user workstations. Once you have set up the library's network interface, users enter the library's host name or IP address into a standards-compliant web browser, such as Mozilla Firefox, open the application in a browser window, log in, and work.
The dashboard is the key part of the interface and appears at the top of every panel. At left, it hosts a remote power button (a vertical bar enclosed by a circle), a remote library-locator button (concentric circles interrupted by a triangle), and, when the library is busy, a Busy... indicator. The dashboard displays the Library Health at center (Operational, Degraded, or Failed) and the connection state of the library (typically Online or Offline) at right. If you click on a Degraded value in the Library Health field, the user interface displays a tabular list of failed and degraded components. The currently logged in user is displayed at far right. When you are ready to end your session, click the Log Out control to its immediate left. This secures the interface and logs you off of the system. The Preferences control lets you Pause Automatic Refresh of the display and Resume Automatic Refresh when ready.
The About link at the bottom right corner of the interface displays the library firmware version followed by build information.
A list-type menu on the left side of the interface controls the screen display:
The Library screen lets you monitor component status and library operations via a graphical representation of the library, complete with modules, drives, storage slots, robot, mailslot, and tape cartridges. When necessary, authorized users can move and eject tape cartridges and clean drives independent of library- or storage-management software. In partitioned libraries, you can limit displays and actions by partition. Library resources that are not assigned to the selected partition are then grayed out in the interface.
The Drives screen displays drive properties in tabular form, with a row for each drive in your library. Each row contains a configurable set of columns that can include the Component position (Top or Bottom), the Module where the drive is installed, the Health of the drive, the drive Type (manufacturer and LTO generation), the drive Interface Type (Fibre or SAS), the Serial Number, the World Wide Node and Port Name that uniquely identify the drive to a Storage Area Network (SAN), and cleaning status.
The Tapes screen displays tape properties in tabular form, with a row for each tape in your library. Each row contains a configurable set of columns that can include the Tape Label, the Current Location of the cartridge, the Module that holds the cartridge, the Location Type (Slot, Reserved Slot, or Drive), the SCSI Address of location, the Tape Type (data, cleaning, or diagnostic), and the Media Type (LTO Generation, WORM status, and capacity.
The Settings screen lets authorized users change the configuration of the library. Service users can change the system time, reserve Library slots, update firmware, change the networking configuration, and change the library partitioning. In addition, the library Administrator can add, remove, and modify user accounts and reassign user roles from this screen.
The Service screen lets authorized users review Product Identification information, Replaceable Component records, and the library Health Log.
The interface lets you individually monitor and administer the partitions of a partitioned library. When you specify a partition with the Partition control at the top of the Library screen, the interface grays out drives, storage slots, tape cartridges, and mailslot that are not assigned to the selected partition.
For information on logging in to the SL150 user interface, see the instructions in Accessing the User Interface.
The SL150 local operator panel lets you check on library status and configuration when you are working directly with the hardware and cannot easily use the browser-based user interface. You can check for health messages, check the meanings of warning LEDs, open the mailslot, and assign the mailslot to the partitions of a partitioned library. But you cannot carry out potentially disruptive system-configuration and administration tasks that are better left to the remote interface.
A dashboard at the top of every screen displays the Library Health at center (Operational, Degraded, or Failed), and the connection state of the library (typically Online or Offline) at right. If you click on a Degraded value in the Library Health field, the user interface displays a tabular list of failed and degraded components.
The Home screen is your starting point for exploring the operator panel. A two-row, button-style menu provides access to information on the main library components. Press buttons in the first row for information on the Library overall, Modules, Magazines, or the Mailslot. Press buttons in the bottom row to see information on Drives, Tapes, or library configuration Settings.
When the Simple Partitioning feature is enabled, the menu contains an additional button for displaying the configuration of the library Partitions:
The operator panel presents much the same information as is available in the browser-based user interface but in a simplified, text-oriented form better suited to the smaller display. Tabbed property sheets and tables take the place of some of the graphics used in the browser-based interface.
Tap a finger on the operator panel touch-screen to move the cursor and select options. Note, however, that the scroll bars in operator panel displays cannot be dragged to a new position, as they can be in a web browser. Instead, you must click on the desired position. The scroll bar will then jump to the new position and scroll the page accordingly.
