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smsfnf.txt
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1994-01-27
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SMS: Facts and Fallacies
by Mike Kidd
Vice President of Marketing, Palindrome Corporation
What is SMS? SMS is an open specification designed to solve the
major industry problems of managing data in heterogenous
environments. It consists of two main components. First, the
System Independent Data Format (SIDF), which specifies a standard
open tape format as well as a method for "packaging" data
independent of the host OS. And second, the Target Service APIs,
which along with the standard Target Service Agents (TSAs), give
storage management software one consistent interface to all
network operating systems. Together, they represent the first
workable solution to the proprietary, vendor dependent problems
that have plagued the LAN storage management industry. At
present, SMS is the only way to reliably back up and restore
NetWare 4.01 and NDS (NetWare Directory Service).
Why is there so much controversy? To support SMS, a vendor
providing backup software must make a fundamental commitment to
supporting an open industry standard. All software calls that
access a file system directly need to be replaced by standardized
SMS calls. The vendor's historically proprietary tape format
must be replaced with the standard, extensible SIDF format. As
in other parts of the data processing industry, conversion from
proprietary solutions to open standards is inconvenient and time
consuming to the vendor, but provides huge benefits to the user.
When an industry goes through the fundamental change from
proprietary to open solutions, there is always a lot of
confusion. Any vendor not fully committed to the change will
implement "semi-standard" solutions as an interim step, and use
any of a number of rationalizations to explain why a fully
compliant solution is not available. SMS is at this threshold
today. The standard is complete, the tools are in place, but few
vendors have yet delivered, creating a fair amount of confusion
in the market. Palindrome is now delivering a complete "SMS
Level Two" compliant solution, and would like to separate the
facts and fallacies surrounding SMS.
Fallacy #1: Lots of vendors are fully supporting SMS.
Fact: Novell has defined two levels of SMS compliance. Level
One describes products that can use standard TSAs to access
network clients. Several vendors have shipped products that can
use TSAs, although many of them still make direct calls to the
file systems, bypassing the standard when convenient.
Palindrome's Network Archivist SMS uses only SMS calls,
supporting the standard fully. In addition, all TSAs developed
and utilized by Palindrome will conform to Novell's
specification, meaning that other SMS based applications will be
able to interoperate with Palindrome supplied TSAs. Proprietary
agents available from other software developers do not
interoperate with SMS applications. Some software vendors use a
mixture of proprietary agents and SMS TSA's, resulting in
increased complexity for users and potential incompatibility with
NetWare revisions.
Level Two compliance requires that the vendor's software not only
use TSAs to access clients, but store their data in the SIDF
standard format. Most "SMS based" products on the market today
can use TSAs to access data, but lock the data into their
proprietary tape formats. To be fair, most have committed to
support SIDF at some point in the future, but only as an
import/export format - continuing to lock normal backups into the
proprietary format. Network Archivist SMS uses SIDF as its
native and only tape format, ensuring long-term compatibility
with all other SIDF compliant applications.
Fallacy #2: SIDF is a moving target.
"...SIDF is still a moving target." - Ed Cooper, Vice President
of Marketing for Legato Systems, Inc. (LAN Times, 11/1/93)
Fact: SIDF is a well-defined, extensible tape format. As new
file systems evolve, the format will be extended, but not without
backward compatibility. Novell is supporting SIDF with SBackup,
and Palindrome, Mountain and System Enhancement Group are
supporting it as well. Data interchange on tape is now a reality
among those vendors that support the standard. Palindrome is
working with the other SIDF compliant vendors to ensure that
media written by one can be read by all.
Fallacy #3: SMS is a good idea, but it's just too slow.
Fact: Palindrome has benchmarked Network Archivist SMS backing
up to a DLT tape drive and has achieved sustained throughput of
non-compressed data in excess of 100 MB per minute. This is real
data (not sparse files) without using NetWare 4.0's data
compression. As the industry moves to NetWare 4.x, the on-disk
compression will make backups even faster, as SMS based
applications can transfer data to tape without decompressing. In
these environments, non-SMS applications will actually be much
slower.
In order to achieve these high speeds, backup vendors may have to
endure the inconvenience of changing some of their file access
methods. The performance is there for those willing to make the
investment.
Fallacy #4: SMS won't catch on because it requires backup
vendors to change.
"It (SMS) imposes Novell's backup philosophy on developers." -
Rod Christensen, Vice President of Engineering at Emeritus. (LAN
Times, 11/1/93)
Fact: Backup as an industry has been among the slowest to adopt
standards, but the same forces that have moved other industries
to standards-based platforms are at work here. Changing to an
open system is never easy or convenient, but it is a growing
customer requirement and it is happening. Palindrome has
delivered a fully SMS Level Two compliant system, and others will
follow in time. (Nearly all have committed to providing Level
One support, and most have committed to at least supporting SIDF
import/export facilities.)
Fallacy #5: There's no way to back up NDS today.
"No one is supporting the (NDS) TSA 100 percent, except through
emulation mode." - Ed Cooper, Vice President of Marketing for
Legato Systems, Inc. (LAN Times, 11/1/93)
Fact: Palindrome shipped support for the NDS TSA with Network
Archivist 3.0 as a separate utility. With Network Archivist SMS,
support for NetWare Directory Services is completely integrated.
An entire directory system can be rebuilt via the NDS TSA.
Bindery emulation is not a workable solution for backing up NDS.
Fallacy #6: SMS isn't "ready for prime time".
Fact: SMS has been evolving for two years, led by Novell with
significant involvement from a number of backup vendors. The
APIs provide a standard, stable and high-performance platform.
TSAs available today back up NetWare 3.x (including all name
spaces), NetWare 4.01 with NDS, DOS, OS/2 and Windows
workstations. In the next few months, TSAs for Macintosh (from
Novell), Unix NFS (from Palindrome) and NetWare 2.x (from Novell)
will be available. Efforts are underway to provide TSAs for
other operating systems and all popular database engines. By the
middle of next year, SMS will be the only workable approach to
managing storage on complex LANs.
Fallacy #7: SMS is just a NetWare-centric specification.
Fact: SMS and SIDF are specifications originally developed by
Novell to solve the growing problems of protecting data in a
heterogenous computing environment. SIDF is now a multi-vendor
standard. The SMS APIs are being ported to other environments.
Palindrome's upcoming Network Archivist for Unix is based on SMS,
using the same APIs and TSA as it's NetWare counterpart. The SMS
specification is portable, the first implementation is on
NetWare.
Summary
SMS is here today. Its benefits - standardized access to clients
in heterogenous environments, faster support for new releases of
NetWare and other operating systems, data interchange and
long-term access to data based on an open tape format - are
available to any vendor willing to make the commitment necessary
to provide full support.
If you want to get all the benefits of a fully SMS compliant
system, ask your vendor these questions:
1. Can your product use TSAs to access servers and clients? Does
it use them exclusively, or does it go around the SMS interface
with direct file system calls? A completely standards-based
solution will use TSAs, and will adhere to the SMS APIs. Direct
access to the file or security system raises the possibility of
nonstandard storage of data, and the necessity for a
vendor-supplied update when the target operating system changes.
2. Does your product read and write SIDF standard tapes? At the
very least, import and export capabilities are required for any
hope of data interchange.
3. Does your product use SIDF as its native format? If the
answer is "no", then you're locking your backups into a
proprietary trap. The only software that will ever be able to
restore that data is from your current vendor. Should you change
brands, or should they go out of business, your retrieval options
are severely limited.
4. Can I do a complete, SMS based backup and restore of a NetWare
4.01 server, including directory services? If not, the SMS
application is not complete.
The LAN backup industry has remained an island of proprietary
formats and protocols. Users have had to wait for each vendor to
supply proprietary agents to each new client on the LAN. Backup
sessions have been locked into nonstandard formats, limiting
user's choices of future backup and storage management
applications. Two years ago, SMS and SIDF were launched to
provide a way out of these proprietary, incompatible systems.
Today, the standard is complete and standards-based backup
systems are here. If reliable backup of heterogenous LANs, quick
support for new OS releases, data interchange and long-term
accessibility of data are important to you, SMS Level Two
compliant backup systems are the only answer.