Windows 2000 Active Directory FSMO roles

This article was previously published under Q197132

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SUMMARY
MORE INFORMATION
Windows 2000 Multi-Master Model
Windows 2000 Single-Master Model
Schema Master FSMO Role
Domain Naming Master FSMO Role
RID Master FSMO Role
PDC Emulator FSMO Role
Infrastructure FSMO Role

SUMMARY
The Microsoft Windows 2000 Active Directory is the central repository in which all objects in an
enterprise and their respective attributes are stored. It is a hierarchical, multi-master enabled database,
capable of storing millions of objects. Because it is multi-master, changes to the database can be processed
at any given domain controller (DC) in the enterprise regardless of whether the DC is connected or
disconnected from the network.

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MORE INFORMATION
Windows 2000 Multi-Master Model

A multi-master enabled database, such as the Active Directory, provides the flexibility of allowing
changes to occur at any DC in the enterprise, but it also introduces the possibility of conflicts that can
potentially lead to problems once the data is replicated to the rest of the enterprise. One way Windows
2000 deals with conflicting updates is by having a conflict resolution algorithm handle discrepancies in
values by resolving to the DC to which changes were written last (that is, "the last writer wins"), while
discarding the changes in all other DCs. Although this resolution method may be acceptable in some cases,
there are times when conflicts are just too difficult to resolve using the "last writer wins" approach. In such
cases, it is best to prevent the conflict from occurring rather than to try to resolve it after the fact.

For certain types of changes, Windows 2000 incorporates methods to prevent conflicting Active Directory
updates from occurring.

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Windows 2000 Single-Master Model

To prevent conflicting updates in Windows 2000, the Active Directory performs updates to certain
objects in a single-master fashion. In a single-master model, only one DC in the entire directory is allowed
to process updates. This is similar to the role given to a primary domain controller (PDC) in earlier
versions of Windows (such as Microsoft Windows NT 3.51 and 4.0), in which the PDC is responsible for
processing all updates in a given domain.

The Windows 2000 Active Directory extends the single-master model found in earlier versions of
Windows to include multiple roles, and the ability to transfer roles to any domain controller (DC) in the
enterprise. Because an Active Directory role is not bound to a single DC, it is referred to as a Flexible
Single Master Operation (FSMO) role. Currently in Windows 2000 there are five FSMO roles:

• Schema master
• Domain naming master
• RID master
• PDC emulator
• Infrastructure daemon

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Schema Master FSMO Role

The schema master FSMO role holder is the DC responsible for performing updates to the directory
schema (that is, the schema naming context or LDAP://cn=schema,cn=configuration,dc=<domain>). This
DC is the only one that can process updates to the directory schema. Once the Schema update is complete,
it is replicated from the schema master to all other DCs in the directory. There is only one schema master
per directory.

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Domain Naming Master FSMO Role

The domain naming master FSMO role holder is the DC responsible for making changes to the forest-
wide domain name space of the directory (that is, the Partitions\Configuration naming context or
LDAP://CN=Partitions, CN=Configuration, DC=<domain>). This DC is the only one that can add or
remove a domain from the directory. It can also add or remove cross references to domains in external
directories.

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RID Master FSMO Role

The RID master FSMO role holder is the single DC responsible for processing RID Pool requests from
all DCs within a given domain. It is also responsible for removing an object from its domain and putting it
in another domain during an object move.

When a DC creates a security principal object such as a user or group, it attaches a unique Security ID
(SID) to the object. This SID consists of a domain SID (the same for all SIDs created in a domain), and a
relative ID (RID) that is unique for each security principal SID created in a domain.

Each Windows 2000 DC in a domain is allocated a pool of RIDs that it is allowed to assign to the security
principals it creates. When a DC's allocated RID pool falls below a threshold, that DC issues a request for
additional RIDs to the domain's RID master. The domain RID master responds to the request by retrieving
RIDs from the domain's unallocated RID pool and assigns them to the pool of the requesting DC. There is
one RID master per domain in a directory.

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PDC Emulator FSMO Role

The PDC emulator is necessary to synchronize time in an enterprise. Windows 2000 includes the
W32Time (Windows Time) time service that is required by the Kerberos authentication protocol. All
Windows 2000-based computers within an enterprise use a common time. The purpose of the time service
is to ensure that the Windows Time service uses a hierarchical relationship that controls authority and does
not permit loops to ensure appropriate common time usage.

The PDC emulator of a domain is authoritative for the domain. The PDC emulator at the root of the forest
becomes authoritative for the enterprise, and should be configured to gather the time from an external
source. All PDC FSMO role holders follow the hierarchy of domains in the selection of their in-bound
time partner.

In a Windows 2000 domain, the PDC emulator role holder retains the following functions:
Password changes performed by other DCs in the domain are replicated preferentially to the PDC
•
emulator.
Authentication failures that occur at a given DC in a domain because of an incorrect password are
•
forwarded to the PDC emulator before a bad password failure message is reported to the user.
• Account lockout is processed on the PDC emulator.
The PDC emulator performs all of the functionality that a Microsoft Windows NT 4.0 Server-based PDC
•
or earlier PDC performs for Windows NT 4.0-based or earlier clients.
This part of the PDC emulator role becomes unnecessary when all workstations, member servers, and
domain controllers that are running Windows NT 4.0 or earlier are all upgraded to Windows 2000. The
PDC emulator still performs the other functions as described in a Windows 2000 environment.

The following information describes the changes that occur during the upgrade process:
Windows 2000 clients (workstations and member servers) and down-level clients that have installed the
• distributed services client package do not perform directory writes (such as password changes)
preferentially at the DC that has advertised itself as the PDC; they use any DC for the domain.
Once backup domain controllers (BDCs) in down-level domains are upgraded to Windows 2000, the PDC
•
emulator receives no down-level replica requests.
• Windows 2000 clients (workstations and member servers) and down-level clients that have installed the
 distributed services client package use the Active Directory to locate network resources. They do not
require the Windows NT Browser service.

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Infrastructure FSMO Role

When an object in one domain is referenced by another object in another domain, it represents the
reference by the GUID, the SID (for references to security principals), and the DN of the object being
referenced. The infrastructure FSMO role holder is the DC responsible for updating an object's SID and
distinguished name in a cross-domain object reference.

NOTE: The Infrastructure Master (IM) role should be held by a domain controller that is not a Global
Catalog server(GC). If the Infrastructure Master runs on a Global Catalog server it will stop updating
object information because it does not contain any references to objects that it does not hold. This is
because a Global Catalog server holds a partial replica of every object in the forest. As a result, cross-
domain object references in that domain will not be updated and a warning to that effect will be logged on
that DC's event log.

If all the domain controllers in a domain also host the global catalog, all the domain controllers have the
current data, and it is not important which domain controller holds the infrastructure master role.

How to view and transfer FSMO roles in

Windows Server 2003
View products that this article applies to.
Article
: 324801
ID
Last Review : December 3, 2007
Revision : 9.5
This article was previously published under Q324801

On This Page

SUMMARY
FSMO Roles
Transfer the Schema Master Role
Register Schmmgmt.dll
Transfer the Schema Master Role
Transfer the Domain Naming Master Role
Transfer the RID Master, PDC Emulator, and Infrastructure Master Roles
REFERENCES
 SUMMARY
This article describes how to transfer Flexible Single Master Operations (FSMO) roles (also known as
operations master roles) by using the Active Directory snap-in tools in Microsoft Management Console
(MMC) in Windows Server 2003.

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FSMO Roles

In a forest, there are at least five FSMO roles that are assigned to one or more domain controllers. The
five FSMO roles are:
Schema Master: The schema master domain controller controls all updates and modifications to the
• schema. To update the schema of a forest, you must have access to the schema master. There can be only
one schema master in the whole forest.
Domain naming master: The domain naming master domain controller controls the addition or removal of
•
domains in the forest. There can be only one domain naming master in the whole forest.
Infrastructure Master: The infrastructure is responsible for updating references from objects in its domain
• to objects in other domains. At any one time, there can be only one domain controller acting as the
infrastructure master in each domain.
Relative ID (RID) Master: The RID master is responsible for processing RID pool requests from all
• domain controllers in a particular domain. At any one time, there can be only one domain controller
acting as the RID master in the domain.
PDC Emulator: The PDC emulator is a domain controller that advertises itself as the primary domain
controller (PDC) to workstations, member servers, and domain controllers that are running earlier
versions of Windows. For example, if the domain contains computers that are not running Microsoft
• Windows XP Professional or Microsoft Windows 2000 client software, or if it contains Microsoft
Windows NT backup domain controllers, the PDC emulator master acts as a Windows NT PDC. It is also
the Domain Master Browser, and it handles password discrepancies. At any one time, there can be only
one domain controller acting as the PDC emulator master in each domain in the forest.
You can transfer FSMO roles by using the Ntdsutil.exe command-line utility or by using an MMC snap-in
tool. Depending on the FSMO role that you want to transfer, you can use one of the following three MMC
snap-in tools:
Active Directory Schema snap-in
Active Directory Domains and Trusts snap-in
Active Directory Users and Computers snap-in
If a computer no longer exists, the role must be seized. To seize a role, use the Ntdsutil.exe utility.

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Transfer the Schema Master Role

Use the Active Directory Schema Master snap-in to transfer the schema master role. Before you can use
this snap-in, you must register the Schmmgmt.dll file.
Register Schmmgmt.dll

1. Click Start, and then click Run.

2. Type regsvr32 schmmgmt.dll in the Open box, and then click OK.
3. Click OK when you receive the message that the operation succeeded.

Transfer the Schema Master Role

1. Click Start, click Run, type mmc in the Open box, and then click OK.
2. On the File, menu click Add/Remove Snap-in.
3. Click Add.
4. Click Active Directory Schema, click Add, click Close, and then click OK.
5. In the console tree, right-click Active Directory Schema, and then click Change Domain Controller.
Click Specify Name, type the name of the domain controller that will be the new role holder, and then
6.
click OK.
7. In the console tree, right-click Active Directory Schema, and then click Operations Master.
8. Click Change.
9. Click OK to confirm that you want to transfer the role, and then click Close.

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Transfer the Domain Naming Master Role

1. Click Start, point to Administrative Tools, and then click Active Directory Domains and Trusts.
Right-click Active Directory Domains and Trusts, and then click Connect to Domain Controller.

2. NOTE: You must perform this step if you are not on the domain controller to which you want to transfer
the role. You do not have to perform this step if you are already connected to the domain controller
whose role you want to transfer.
Do one of the following:
In the Enter the name of another domain controller box, type the name of the domain controller
that will be the new role holder, and then click OK.
•
3.
-or-
In the Or, select an available domain controller list, click the domain controller that will be the new
•
role holder, and then click OK.
In the console tree, right-click Active Directory Domains and Trusts, and then click Operations
4.
Master.
5. Click Change.
6. Click OK to confirm that you want to transfer the role, and then click Close.

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Transfer the RID Master, PDC Emulator, and Infrastructure Master Roles

1. Click Start, point to Administrative Tools, and then click Active Directory Users and Computers.
Right-click Active Directory Users and Computers, and then click Connect to Domain Controller.

2. NOTE: You must perform this step if you are not on the domain controller to which you want to transfer
the role. You do not have to perform this step if you are already connected to the domain controller
whose role you want to transfer.
Do one of the following:
In the Enter the name of another domain controller box, type the name of the domain controller
that will be the new role holder, and then click OK.
•
3.
-or-
In the Or, select an available domain controller list, click the domain controller that will be the new
•
role holder, and then click OK.
In the console tree, right-click Active Directory Users and Computers, point to All Tasks, and then
4.
click Operations Master.
Click the appropriate tab for the role that you want to transfer (RID, PDC, or Infrastructure), and then
5.
click Change.
6. Click OK to confirm that you want to transfer the role, and then click Close.

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REFERENCES
For additional information about a related topic, click the following article number to view the article in
the Microsoft Knowledge Base:
255690 (http://support.microsoft.com/kb/255690/) How to view and transfer FSMO roles in the graphical
user interface

Linear Tape-Open
From Wikipedia, the free encyclopedia

Jump to: navigation, search

LTO-2 cartridge

Linear Tape-Open (or LTO) is a magnetic tape data storage technology originally developed in the late
1990s as an open standards alternative to the proprietary magnetic tape formats that were available at the
time. Seagate, Hewlett-Packard, and IBM initiated the LTO Consortium, which directs development and
manages licensing and certification of media and mechanism manufacturers. The standard form-factor of
LTO technology goes by the name "Ultrium", the original version of which was released in 2000 and could
hold 100 GB of data in a single cartridge. The most recent version was released in 2007 and can hold 800
GB in the same size cartridge. Since 2002, LTO has been the best selling "super tape" format and is widely
used with small and large computer systems, especially for backup. Its popularity can be attributed to both
the innovative technology developed as well as the attractive pricing that is the result of the competitive
market made possible by an open standard.

[edit] Historical context

Half-inch (1/2") magnetic tape has been used for data storage for more than 50 years. In the mid 1980s,
IBM and DEC put this kind of tape into a single reel, enclosed cartridge. IBM called their cartridge 3480
and DEC originally called theirs CompacTape, but later it was renamed DLT and sold to Quantum. In the
late 1990s, Quantum's DLT and Sony's Advanced Intelligent Tape (AIT) were the leading options for
high-capacity, high speed tape storage for PC servers and UNIX systems. Those technologies were and
still are tightly controlled by their owners. Consequently, their availability was fairly limited and prices
were relatively high.

IBM, HP and Seagate sought to counter this by introducing a more open format.[1] Much of the technology
is an extension of the work done by IBM at its Tucson lab during the previous 20 years.[2]

Around the time of the release of LTO-1, Seagate's magnetic tape division was spun off as Seagate
Removable Storage Systems, later renamed Certance which, soon after, was acquired by Quantum Corp.

[edit] Form factors

LTO technology was designed to come in two form factors, Ultrium and Accelis. As of 2008, LTO
Ultrium is very popular and there are no commercially available LTO Accelis drives or media. In common
usage, LTO generally refers only to the Ultrium form factor.

[edit] Accelis

Accelis was developed in 1997 for fast access to data by using a two-reel cartridge that loads at the
midpoint of the 8 mm wide tape to minimize access time. IBM's (short-lived) 3570 Magstar MP product
pioneered this concept. The real-world performance never exceeded that of the Ultrium tape format, so
there was never a demand for Accelis and no drives or media were commercially produced.

[edit] Ultrium

LTO Ultrium was developed as a (more or less) drop-in replacement for DLT and has a similar design of
1/2" wide tape in a (slightly smaller) single reel cartridge. This made it easy for robotic tape library
vendors to convert their DLT libraries into LTO libraries.

An Ultrium cartridge's dimensions are 102.0 x 105.4 x 21.5 (mm).

• An Ultrium drive is expected to read data from a cartridge in its own generation and at least the
two prior generations.
• An Ultrium drive is expected to write data to a cartridge in its own generation and to a cartridge
from the immediate prior generation in the prior generation format.

[edit] Generations
Generation LTO-1 LTO-2 LTO-3 LTO-4 LTO-5 LTO-6
Release Date 2000 2003 2005 2007 TBA TBA
Native Data Capacity 100 GB 200 GB 400 GB 800 GB 1.6 TB 3.2 TB
Max Speed (MB/s) 15 40 80 120 180 270
WORM Capable? NO NO YES YES PLANNED PLANNED
Tape Thickness 8.9 μm 8.9 μm 8 μm 6.6 μm
Tape Length 609 m 609 m 680 m 820 m
Tape Tracks 384 512 704 896
Write Elements 8 8 16 16
Wraps per Band 12 16 11 14
Linear Density (bits/mm) 4880 7398 9638 13300?
Encoding RLL 1,7 PRML PRML PRML?

[edit] LTO-1
 • Originally designed to come in 4 lengths of tape: 10, 30, 50, and 100 GB.
• Tape encoding is RLL 1,7
• First commercially available in September 2000.[3]

[edit] LTO-2

• Doubled capacity and transfer speed

• Switched to PRML encoding
• First mechanisms approved in February 2003.[4] First media approved in March 2003.[5]

[edit] LTO-3

• Doubled capacity and transfer speed again

• Introduced WORM feature
• Doubled number of write elements in head
• First media approved in November 2004.[6]

At the full native data rate (80 MB/s), LTO-3 drives can write data faster than most hard disk drives can
read. Even the minimum streaming data rate (~30–40 MB/s) is faster than many hard disk drives.

[edit] LTO-4

• Doubled capacity again to 800 GB.

• Added 256-bit AES-GCM drive level encryption.
• Increase data transfer rate by 50% to 120 MB/s.
• First mechanisms approved in April 2007.[7] First media approved in May 2007.[8]

[edit] Notes

• Data Capacity and Speed figures above are for uncompressed data. Most manufacturers list
compressed capacities on their marketing material. Capacities are often stated on tapes as double
the actual value; they assume that data will be compressed with a 2:1 ratio (IBM uses a 3:1
compression ratio in the documentation for its Mainframe tape drives. Sony uses a 2.6:1 ratio for
SAIT). See LTO-DC below. The marketing material also uses decimal definitions for byte
capacities.
• The units for data capacity generally follow the (decimal) SI prefix convention. (eg. mega = 10^6)
• The units for data transfer generally follow the binary prefix convention. (eg. mega = 2^20)
• Minimum and maximum reading and writing speeds are drive dependent.
• Tape speed adjusts to available data stream, within the minimum and maximum streaming speeds.

[edit] Positioning times

Maximum rewind time is 98 seconds.[citation needed] Note that due to the back and forth writing, rewinding
rarely takes this long. If a tape is written to full capacity, there is no rewind time, since the last pass is a
reverse pass leaving the head at the beginning of the tape. Although this depends on the block size used
when writing to the tape as the end of the tape could also be at the tape head when the writing is complete.
Average tape seek/filemark search time is 75 seconds.[citation needed] Although these times vary with the type of
LTO drive that you have and the overall drive performance.

[edit] Tape durability

Estimated

• 1.2 million passes[citation needed]

• 30 years of archival storage[citation needed]
• 20,000 loads and unloads[citation needed]

To fill up a tape, LTO requires 48 passes, LTO-2 requires 64 passes, LTO-3 requires 44 passes, and LTO-4
requirs 56 passes. So the actual life of the tape is somewhat shorter than 1.2 million uses, total.

But even for LTO-2, which requires the most passes to span the entire tape, this still amounts to an
estimated tape life of 18,750 full-tape reads and writes, which is 50 years of use when fully writing a tape
every day.

[edit] Technical features

[edit] Error detection and correction

The tapes contain a strong error correction algorithm that makes data recovery possible when lost data is
within one track or up to 32 mm of the tape medium.[citation needed] When data is written to the tape it is
verified by reading it back using the read heads that are positioned just 'behind' the write heads. This
allows the drive to write a second copy of any data that fails the verify without the help of the host system.

[edit] Leader pin

Leader pin on the end of a length of LTO tape

The tape inside an LTO cartridge is wound around a single reel. The end of the tape is attached to a
perpendicular leader pin that is used by an LTO drive to reliably grasp the end of the tape and mount it in a
take-up reel inside the drive. When a cartridge is not in a drive, the pin is held in place at the opening of
the cartridge with a small spring.
A common reason for a cartridge failing to load into a drive is the misplacement of the leader pin as a
result of the cartridge having been dropped. The plastic slot where the pin is normally held is deformed by
the drop and the leader pin is no longer in the position that the drive expects it to be.

Older tape technologies used different means to load tape onto a take-up reel. Some 9 track tape drives
used a burst of air against the spinning reel to automatically separate and grasp the loose end of the tape.
This worked without a leader pin. DLT tapes have a hole punched in the end of the tape that a drive can
use to grasp the end of the tape.

[edit] LTO-CM

LTO-CM

Every LTO cartridge has a Cartridge Memory chip inside it. It is made up of 128 blocks of memory, where
each block is 32 Bytes for a total of 4096 Bytes. This memory can be read and/or written, 1 block at a
time, via a non contacting passive RF interface. This memory is used to identify tapes and to help drives
discriminate between the different generations of the technology.

Every LTO drive has a CM Reader in it. External readers are available, both built into tape libraries and
handheld. The non-contact interface has a range of 20 mm.[9]

[edit] LTO-DC

The LTO specification describes a Data Compression method LTO-DC, also called Streaming Lossless
Data Compression (SLDC)[10]. It is very similar to the algorithm ALDC[11] which is a variation of LZS (a
patent-encumbered algorithm controlled by Hi/Fn[12]).

The primary difference between ALDC and SLDC is that SLDC does not apply the compression algorithm
to uncompressible data (i.e. data that is already compressed or sufficiently random to defeat the
compression algorithm). Every block of data written to tape has a header bit indicating whether the block
is compressed or raw. For each block of data that the algorithm works on, it saves a copy of the raw data.
After applying the compression function to the data, the algorithm compares the "compressed" data block
to the raw data block in memory and writes the smaller of the two to tape. Every data compression
algorithm will end up increasing the size of some inputs. The extra bit used by SLDC to differentiate
between raw and compressed blocks effectively places an upper bound on this data expansion.

LTO-DC achieves an approximately 2:1 compression ratio when applied to the Calgary Corpus. This is
inferior to slower algorithms such as gzip, but similar to lzop and the high speed algorithms built into other
tape drives. It should be noted that plain text, raw images, and database files (TXT, ASCII, BMP, DBF,
etc.) typically compress much better than other types of data stored on computer systems. In contrast,
encrypted data and pre-compressed data (PGP, ZIP, JPEG, MPEG, MP3, etc.) would normally increase in
size, if data compression was applied. In some cases this data expansion could be as much as 15%. With
the SLDC algorithm, this significant expansion is avoided.

[edit] Tape layout

LTO Ultrium tape is laid out with 4 wide data bands sandwiched between 5 narrow servo bands. The data
bands are numbered 3,1,0,2 across the tape and are filled individually, in numeric order. The head unit
straddles the 2 servo bands that border the data band that is being written or read. The servo bands are used
to keep the head precisely aligned within the data band.

Data tracks are written in forward and reverse passes, also called wraps. It takes several wraps to
completely fill a data band. All of the write elements in the head write simultaneously as the head passes
over the data band from the physical start of the tape to the physical end. This makes one forward wrap. At
the end, the head shifts to line up the write elements with a new set of tracks within the same data band. It
is now ready to make a reverse wrap. All tracks written by the same write element in the same direction
are grouped together. This leads to a set of serpentine patterns in each data band. To determine the number
of passes required to fill up a tape, divide the total number of tracks by the number of write elements. For
example, an LTO-2 tape requires 64 passes.

The block structure of the tape is logical so inter block gaps, file marks, tape marks and so forth take only
a few bytes each. In LTO-1 this logical structure has CRC codes and compression added to create blocks
of 403884 bytes. Another chunk of 468 bytes of information (including statistics and information about the
drive that wrote the data and when it was written) is then added to create a 'dataset'. Finally error
correction bytes are added to bring the total size of the dataset to 491520 bytes before it is written in a
specific format across the eight heads. The formats for LTO-2 and LTO-3 are similar.

[edit] WORM

New for LTO-3 is Write Once Read Many (WORM) capability. This is normally only useful for legal
record keeping. An LTO-3 drive will not erase or overwrite data on a WORM cartridge, but will read it.
An LTO-3 WORM Cartridge is identical to a normal LTO-3 tape cartridge except its LTO-CM chip
identifies it to the drive as WORM. There is nothing different about the tape medium in a WORM
cartridge. Typically the WORM cartridges have a different color packaging.

[edit] Caution
[edit] Cleaning

Normal cleaning cartridges are abrasive and frequent use will shorten the drive's lifespan. HP LTO drives
have a cleaning strategy[13] that will prevent the drive from actually using the cleaning tape if it is not
needed. There is an internal mechanism that also handles cleaning tasks based on error rate criteria and
time. The internal tape head cleaner is also activated when the cleaning cartridge is loaded.

[edit] Erasing
The magnetic servo tracks on the tape are factory encoded. Using a bulk eraser (or otherwise exposing the
cartridge to a strong magnetic field) will erase the servo tracks along with the data tracks and make the
cartridge unusable.

[edit] Cartridges

LTO-2 Cartridge with the top shell removed, showing the internal components

Compliance-Verified licensed manufacturers of LTO technology media are Maxell, TDK, Imation,
EMTEC, Fujifilm, and Sony.[14] All other brands of media are manufactured by these companies under
contract. Since its bankruptcy in 2003, EMTEC no longer manufactures LTO media products. Verbatim[15]
and Quantegy[16] both licensed LTO technology, but never manufactured their own compliance-verified
media.

[edit] Colors

HP's Dark Red LTO-2 cartridge

The colors of LTO Ultrium cartridge shells are somewhat standardized. HP is the notable exception.

UCC LTO-1 LTO-2 LTO-3 LTO-4

EMTEC Black Black Purple
FujiFilm Black Purple Slate-Blue Green
HP Orange Blue Dark Red Yellow Green
IBM Black Purple Slate Blue Green
Imation Black Purple Blue-Gray Teal
Maxell Gray Black Purple Blue-Gray Teal
Overland Teal
Quantum Black Black Purple Blue
RPS Black Purple
 Sony Black Purple Gray
StorageTek Purple
Tandberg Grey Black Purple Blue-Gray
TDK Gray Black Purple Blue-Gray Blue-Green
Verbatim Black Purple Blue-Gray

• UCC means Universal Cleaning Cartridge, which works with all drives.
• Different manufactures use different names for the same color sometimes. The names in the table
above come from each manufacturers' own documentation.
• WORM (Write Once, Read Many) cartridges are two-tone, the top half of the shell is the normal
color of that generation for that manufacturer, and the bottom half of the shell is a light gray.

[edit] Labels

The LTO cartridge label uses the bar code symbology of USS-39. A description and definition is available
from the Automatic Identification Manufacturers (AIM) specification Uniform Symbol Specification
(USS-39) and the ANSI MH10.8M-1993 ANSI Barcode specification.

[edit] Mechanisms

HP Half-Height LTO drive in an enclosure for desktop use

Current Compliance-Verified licensed manufacturers of LTO technology mechanisms are IBM, Hewlett-
Packard, Quantum, and Tandberg Storage.[14]

[edit] Sales figures

The presence of 5 certified media manufacturers and 4 certified mechanism manufacturers has produced a
competitive market. This has led to attractive prices for customers and subsequently, high sales volumes
for manufacturers. In 2002, LTO out-shipped SDLT by nearly 2 to 1. Sales since then have dominated
other "super" formats (SDLT, SAIT).

Total Cartridges Total

Drives sold
Year drives sold sold cartridges sold
this year [17]
(as of Sept.) [18] this year (as of Sept.) [18]
2001 1,000,000
 2002 175,000
2003 262,000 350,000 (July)
2004 354,000
2005 461,000 1,000,000 30,000,000
2006 [19] 1,500,000 50,000,000
2007 [20] 2,000,000 80,000,000

[edit] References
1. ^ LTO (November 4, 1997). "HP, IBM, And SEAGATE Agree To Establish Open Format
Specifications For Enterprise And Network Storage". Press release. Retrieved on 2007-10-15.
2. ^ IBM storage history
3. ^ LTO (November 05, 2001). "Linear Tape-Open Program Ships One Million Ultrium Tapes in
First 12 Months of Availability". Press release.
4. ^ LTO (February 12, 2003). "HP, IBM Pass LTO Ultrium Format Generation 2 Mechanism
Compliance". Press release.
5. ^ LTO (March 27, 2003). "LTO Program Announces LTO Ultrium Generation 2 Compliance-
Verified Licenses". Press release.
6. ^ LTO (November 08, 2004). "Fujifilm, Imation, Maxell, Sony, TDK Pass LTO Ultrium
Generation 3 Data Interchange Compliance Testing". Press release.
7. ^ LTO (April 11, 2007). "HP And IBM Pass Mechanism Compliance Testing For LTO Ultrium
Format Generation 4 Tape Drives". Press release. Retrieved on 2007-10-15.
8. ^ LTO (May 7, 2007). "Fujifilm, Imation, Maxell, Sony and TDK Pass LTO Ultrium Generation 4
Data Interchange Compliance Testing". Press release.
9. ^ Fujitsu Cartridge Memory documentation
10. ^ ECMA 321 – Specification of SLDC
11. ^ IBM ALDC documentation
12. ^ Patent claim by Hi/Fn
13. ^ HP cleaning strategy
14. ^ a b LTO Compliance-Verified Licencees
15. ^ LTO (August 3, 1998). "EMTEC, IMATION, and VERBATIM License Linear Tape-Open
Technology". Press release.
16. ^ LTO (October 21, 1998). "Linear Tape-Open (LTO) Technology Continues Licensee Momentum
with Signing of Fujitsu and Quantegy". Press release.
17. ^ Freeman Reports
18. ^ a b LTO consortium press releases
19. ^ LTO (September 25, 2006). "LTO Ultrium Format Maintains Momentum With More Than
1,500,000 Tape Drives And 50,000,000 Cartridges Shipped". Press release. Retrieved on 2007-10-
15.
20. ^ LTO (September 5, 2007). "More than 2,000,000 LTO Ultrium Format Tape Drives and
80,000,000 Cartridges Shipped". Press release. Retrieved on 2008-03-13.

[edit] External links

• IBM's LTO Redbook – IBM System Storage Tape Library Guide for Open Systems
 • Linear Tape Open – Consortium Homepage
• www.tandbergdatacorp.com/support/LTO1_2TapeUsersGuideFeb2.pdf Tandberg drive manual
with lots of generic details (link inactive as of 2008-05-18)
• TDK brochure with a diagram of tape and cartridge construction
• ECMA 319 – Specification of Ultrium 1
• IBM LTO Ultrium Cartridge Label Specification, Revision 3
• An online generator for LTO barcode labels

[edit] See also

Wikimedia Commons has media related to:

Linear Tape-Open

• Magnetic tape
• Tape drive
• Tape library
• Data compression

[hide]
v•d•e
Magnetic tape data storage formats
Linear Helical
Three
Sony DIR (19xx) ·
Quarter Inch LINCtape (1962) · DECtape (1963)
Ampex DST (1992)
(19 mm)
UNISERVO (1951) · IBM 7 track (1952) · 9 track (1964) · IBM
Redwood SD-3 (1995) ·
Half Inch 3480 (1984) · DLT (1984) · IBM 3590 (1995) · T9840 (1998) ·
DTF (19xx) · SAIT
(12.65 mm) T9940 (2000) · LTO Ultrium (2000) · IBM 3592 (2003) · T10000
(2003)
(2006)
Eight Data8 (1987) · Mammoth
Millimeter Travan (1995) · IBM 3570 MP (1997) · ADR (1999) (1994) · AIT (1996) ·
(8 mm) VXA (1999)
Quarter Inch
QIC (1972) · SLR (1986) · Ditto (1992)
(6.35 mm)
Eighth Inch KC Standard, Compact Cassette (1975) · HP DC100 (1976) ·
DDS/DAT (1989)
(3.81 mm) Commodore Datassette (1977) · DECtapeII (1979)
Stringy
Exatron Stringy Floppy (1979) · ZX Microdrive (1983) · Rotronics
(1.58–1.9
Wafadrive (1984)
mm)
Retrieved from "http://en.wikipedia.org/wiki/Linear_Tape-Open"
Categories: Computer storage tape media | Computer storage devices
Hidden categories: All articles with unsourced statements | Articles with unsourced statements since March
2008

Disaster recovery
From Wikipedia, the free encyclopedia

Jump to: navigation, search

This article is about business continuity planning. For societal disaster recovery, see emergency
management.
For other uses, see DRP.

Disaster recovery is the process, policies and procedures of restoring operations critical to the resumption
of business, including regaining access to data (records, hardware, software, etc.), communications
(incoming, outgoing, toll-free, fax, etc.), workspace, and other business processes after a natural or human-
induced disaster.

To increase the opportunity for a successful recovery of valuable records, a well-established and
thoroughly tested disaster recovery plan must be developed. This task requires the cooperation of a well-
organized committee led by an experienced chairperson. [1]

A disaster recovery plan (DRP) should also include plans for coping with the unexpected or sudden loss of
communications and/or key personnel, although these are not covered in this article, the focus of which is
data protection. Disaster recovery planning is part of a larger process known as business continuity
planning (BCP).

Contents
[hide]

• 1 Introduction
• 2 Disaster Recovery Strategies
• 3 References
• 4 See also
• 5 Further reading

• 6 External links

[edit] Introduction
As the disaster recovery market continues to undergo significant structural changes, the shift presents
opportunities for companies that specialize in business continuity planning and offsite data protection.

With the rise of information technology and the reliance on business-critical information the importance of
protecting irreplaceable data has become a business priority in recent years. This is especially evident in
information technology, with most companies relying on their computer systems as critical infrastructure
in their business. As a result, most companies are aware that they need to backup their digital information
to limit data loss and to aid data recovery.

Most large companies spend between 2% and 4% of their IT budget on disaster recovery planning; this is
intended to avoid larger losses. Of companies that had a major loss of computerized data, 43% never
reopen, 51% close within two years, and only 6% will survive long-term.[2]

[edit] Disaster Recovery Strategies

Prior to selecting a Disaster Recovery strategy, the Disaster Recovery planner should refer to their
organization's business continuity plan which should indicate the key metrics of Recovery Point Objective
(RPO) and Recovery Time Objective (RTO) for various business processes (such as the process to run
payroll, generate an order, etc). The metrics specified for the business processes must then be mapped to
the underlying IT systems and infrastructure that support those processes.

Once the RTO and RPO metrics have been mapped to IT infrastructure, the DR planner can determine the
most suitable recovery strategy for each system. An important note here however is that the business
ultimately sets the IT budget and therefore the RTO and RPO metrics need to fit with the available budget.
While most business unit heads would like zero data loss and zero time loss, the cost associated with that
level of protection may make the desired high availability solutions impractical.

The following is a list of the most common strategies for data protection.

• Backups made to tape and sent off-site at regular intervals (preferably daily)
• Backups made to disk on-site and automatically copied to off-site disk, or made directly to off-site
disk
• Replication of data to an off-site location, which overcomes the need to restore the data (only the
systems then need to be restored or synced). This generally makes use of Storage Area Network
(SAN) technology
• High availability systems which keep both the data and system replicated off-site, enabling
continuous access to systems and data

In many cases, an organization may elect to use an outsourced disaster recovery provider to provide a
stand-by site and systems rather than using their own remote facilities.

In addition to preparing for the need to recover systems, organizations must also implement precautionary
measures with an objective of preventing a disaster situation in the first place. These may include some of
the following:

• Local mirrors of systems and/or data and use of disk protection technology such as RAID
 • Surge Protectors — to minimize the effect of power surges on delicate electronic equipment
• Uninterruptible Power Supply (UPS) and/or Backup Generator to keep systems going in the event
of a power failure
• Fire Preventions — more alarms, accessible fire extinguishers
• Anti-virus software and other security measures

[edit] References
1. ^ Buchanan, Sally. "Emergency preparedness." from Paul Banks and Roberta Pilette. Preservation
Issues and Planning. Chicago: American Library Association, 2000. 159-165. ISBN 978-0-8389-
0776-4
2. ^ Hoffer, Jim. "Backing Up Business - Industry Trend or Event." Health Management Technology,
Jan 2001 [1]

[edit] See also

• Backup site
• Business Continuity Planning (BCP)
• Continuous data protection
• IBM Global Mirror
• Recovery Point Objective (RPO)
• Recovery Time Objective (RTO)
• Remote backup services
• Secure Virtual Office
• Seven tiers of disaster recovery
• Virtual Tape Library
• Civil Air Patrol

[edit] Further reading

• Gregory, Peter H. (2008). IT Disaster Recovery Planning for Dummies. Wiley Publishing, Inc.
• Cummings, E., Haag, S., & McCubbrey D. (2005). Management Information Systems for the
Information Age. McGraw-Hill Ryerson Higher Education.
• Benton, Dick (2007). Disaster Recovery: A Pragmatist's Viewpoint. Disaster Recovery Journal.
• Tennant, Roy. “Digital Libraries- Coping with Disasters.” Library Journal. 15 November 2001.

Gatlin, Heather. 2006. The Search for a Theoretical Framework for Long-Term Disaster Recovery: A
Normative Application of Jane Addams Social Democratic Theory and Ethics. Applied Research Project.
Texas State University. http://ecommons.txstate.edu/arp/125/

[edit] External links

• Disaster Recovery World
 • Continuity Central - IT Disaster Recovery related articles
• The Disaster Recovery Guide
• Disaster Recovery Institute International
• Federal Emergency Management Agency

Retrieved from "http://en.wikipedia.org/wiki/Disaster_recovery"

Definitions of Disaster recovery on the Web:

• A plan for re-establishing or reproducing computer operations after a catastrophic event, such as a fire or
earthquake. ...
support.previser.com/documentation/UsingPreviser/Appendixes/techgloss_entries.htm
• The ability to recover from the loss of a complete site, whether due to natural disaster or malicious intent. ...
www.microsoft.com/windowsserversystem/storage/storgloss.mspx
• The operation of restoring record collections and related operations after a disaster
secint33.un.org/unarms/en/unrecordsmgmt/unrecordsresources/glossaryofrecordkp.html
• See: IT Service Continuity Management
www.infodiv.unimelb.edu.au/knowledgebase/itservices/a-z/d.html
• (DR) is a coordinated activity to enable the recovery of IT/business systems due to a disruption. DR can be
achieved by restoring IT/business operations at an alternate location, recovering IT/business operations
using alternate equipment, and/or performing some or all of the affected business ...
www.michigan.gov/cybersecurity/0,1607,7-217-34415---,00.html
• the process of recovering from an emergency, including the immediate aftermath and the priorities for the
critical business functions which need to be resumed.
www.cabinetoffice.gov.uk/csia/ia_governance/content/glossary.aspx
• A disaster recovery plan describes how an organization is to deal with potential disasters. Just as a disaster
is an event that makes the ...
www.nmsbvi.k12.nm.us/Records/records_def.htm
• The documented process for protecting and restoring critical information during emergency or disaster
conditions, such as the loss of a computer ...
www.southportllc.com/glossary.htm
• The retrieval and preservation of records damaged or distressed by an unexpected catastrophic occurrence
such as fire or flooding. The recovery process includes repairing buildings and restoring an agency's critical
business functions.
www.mnhs.org/preserve/records/recordsguidelines/guidelinesglossary.html
• Preventative measures using redundant hardware, software, data centers and other facilities to ensure that
a business can continue operations ...
www.storsoftcorp.com/Glossary.htm
• The use of alternative network circuits to re-establish communications channels in the event that the primary
channels are disconnected or malfunctioning.
www.region-s.de/technik/glossary.htm
• Also referred to as Business Continuity, this is a pre-planned and often rehearsed process intended to
provide keep the organisation operating in the event of up to serious or catastrophic events such as floods,
fire or terrorist activity.
www.mitial.com/index.php
• In mission critical operations, a Disaster Recovery site (DR site) can be set up to ensure that operations will
continue no matter what disaster strikes the company. As it is true in all aspects of the technical world, there
 are many levels of DR. ...
nightanddaydba.com/index_files/Page507.htm
• Disaster Recovery is the process, policies and procedures of restoring operations critical to the resumption
of business, including regaining ...
en.wikipedia.org/wiki/Disaster recovery