Merciful 1/Merciful - Disc 1.iso/software/m/mr_backup/mr_backup.txt

Text File | 1995-10-14 | 59KB | 1,312 lines

MRBACKUP PROFESSIONAL

Welcome to MRBackup Professional!

Introduction
------------
MRBackup is a hard disk backup program for the Commodore Amiga family of
computers. It provides a wide range of services to support Amiga file
management and backup/restore of files to/from hard disk. Files can be
backed up to:

 · Floppy disk, in AmigaDOS format

 · Floppy disk, in a special "fast" format

 · Any sequential file or device (local or networked) in "fast" format

 · SCSI streaming tape

A saveset catalog file is created for each saveset, allowing quick
retrieval of individual files when necessary. Should the catalog file
become damaged or lost, MRBackup can recreate it by scanning the saveset.

MRBackup is designed to behave well in your Amiga's multi-tasking
environment. It does not "take over the machine" and will allow you to use
your Amiga for other chores while backups are being performed. MRBackup is
controlled by a flexible set of user-configurable parameters and offers a
wide range of backup and restore options. Its Intuition-based user
interface is designed for a pleasing appearance and ease of operation.
MRBackup uses the Amiga's speech capabilities to provide an effective means
for presenting prompts, error conditions and requests for floppy disk
insertions, etc. MRBackup provides optional data compression which will
reduce the number of diskettes (or other media) required for a backup.

Requirements
· any Amiga system with at least 1 MB memory and AmigaDOS 2.04 or higher

· at least 1 floppy disk drive or SCSI streaming tape drive (Archive Viper,
 Wangtek 50XX, TEAC 36XX, Sony DAT, etc. )

MRBackup will work with any hard drive supported by the AmigaDOS operating
system.

Installation Instructions
-------------------------
As always, prior to installing any new software, make a working copy of the
original diskette. Use the working copy, not the original diskette, for
the installation process. The new installation procedure for MRBackup
Professional will copy all files to a disk partition or a directory within
a partition (recommended). MRBackup's support files have been grouped
according to category into several subdirectories which will be created
within the partition or directory which you specify for installation. You
may wish to make backup copies of any ".init" or filter files which you
created for use with previous versions of MRBackup Professional. They are
still upward compatible with this release of the software.

Insert the MRBackup Professional working copy disk into an available floppy
drive and double-click on its disk icon. Find the icon labeled
"Install-MRBackup" and double-click it. This will run a script which will
install MRBackup Professional.

IMPORTANT NOTE: this version of the software requires the definition of an
AmigaDOS logical name, MRBackup:. This name is equated to the name of the
partition or directory where MRBackup Professional is installed and must be
created/assigned prior to installation. Example:

 MAKEDIR DH0:MRBackup
 ASSIGN MRBackup: DH0:MRBackup

It is recommended that you also place the ASSIGN statement in your
startup-sequence (s:StartupII, s:user-startup, etc.) to assure that the
MRBackup: logical name will always be available whenver you reboot your
system.

The MRBackup: Directory
-----------------------
This section briefly describes the contents of the MRBackup directory.
None of the subdirectories in this directory are an absolute requirement
but it is strongly suggested that you adopt this configuration.

Files in the MRBackup: Directory

The following files will be found at the top level of the MRBackup:
directory.

Compressor
This program file is MRBackup Professional's data compression "engine". It
is automatically started by MRBackup Professional when data compression or
decompression is requested.


FormatDisk
This is a shell script file, invoked by MRBackup Professional when a backup
disk is to be formatted (AmigaDOS backup mode). DO NOT use this script for
general-purpose formatting of disks as it is not intended for that purpose.


MRBackup
This is the MRBackup Professional program file.

Subdirectories in the MRBackup: Directory
-----------------------------------------
The MRBackup: directory contains several subdirectories. These
subdirectories provide a means for grouping files with a similar purpose.

ARexx_Scripts
This directory contains a number of example ARexx scripts for use with
MRBackup Professional. Use these as a guide for writing your own ARexx
scripts.

Catalogs
Use this directory as a repository for catalog files created by the backup
process.

Docs
This directory contains several small document files providing additional
information and details not available in the user manual. The file named
Changes in this directory describes last-minute changes that could not be
included in the user manual.

Lists and Logs
Use this directory to store listing and log files created by MRBackup
Professional.

Prefs
This directory contains various MRBackup Professional "preferences" files
including the MRBackup.init file and the filter file templates. You may
also use this directory to save your custom preferences files.

Work
This is the default MRBackup working directory, used to store temporary
files created by MRBackup during backup and restore operations.

Operation
This manual assumes that you already know the basic operating principles of
your Amiga and that you are familiar with its user interface. If this
manual refers to an Amiga-specific procedure or feature with which you are
not familiar, please refer to your Amiga owner's manual.

MRBackup may be started from the WorkBench by double-clicking its program
icon or from the CLI by typing the appropriate command line. The startup
procedures for each environment are presented below.

Working Directory
MRBackup requires an area for storing certain temporary information during
the backup process. This area is called the "working directory". The
working directory defaults to MRBackup:Work, but you may override this
setting. The next two sections describe how this is done.

MRBackup may be run from either the Command Line Interface (CLI) or the
WorkBench.

CLI Operation
To start MRBackup from the CLI (Command Line Interface, also called the
"Shell"), you can just type MRBackup at the command prompt. MRBackup
supports several command-line options which override its default behavior.
These are: -d <default_directory> This option instructs MRBackup to search
<default_directory>, rather than MRBackup:Prefs, when looking for
preferences files.

-i <init_file>

This option instructs MRBackup to initialize from <init_file>, rather than
MRBackup:Prefs/MRBackup.init or MRBackup.init in the local directory.

-p <default_directory>

This option is essentially the same as the -d option.

-w <work_directory>

This option instructs MRBackup to use <work_directory>, rather than
MRBackup:Work, as the working directory.

WorkBench Operation
To start MRBackup from the WorkBench, simply double-click its program icon
or an MRBackup project icon. MRBackup supports several icon Tool Types
entries which can override its default behavior. To add or modify the Tool
Types entries, you must use the Info command in the WorkBench menu. Refer
to your Amiga owner's manual if you are unfamiliar with this procedure.

MRBackup recognizes the following Tool Types entries:

DIR=<default_directory>
PREFS=<default_directory>

These Tool Types are identical and instruct MRBackup to search
<default_directory>when attempting to locate the preferences file.

WINDOW=<console_spec>

This Tool Type entry instructs MRBackup to open its "background" console
window according to <console_spec> which should be a valid CON: window
specification (e.g. CON:0/0/640/200/MRBackup ).

WORK=<work_directory>

This Tool Type instructs MRBackup to use <work_directory>, rather than
MRBackup:Work, as the default working directory.

If you really want to get clever, you can make copies of MRBackup's project
icon file (MRBackupDefault.info) and tune the Tool Types entries for each
hard disk partition. How is this done? Using the CLI COPY command, make a
copy of MRBackupDefaults.info for each partition. Example:

 (CD to the directory where MRBackup resides)
 COPY MRBackupDefaults.info MRBackup-DH0.info
 COPY MRBackupDefaults.info MRBackup-DH1.info
 (etc.)

For each icon, make the appropriate changes to the Tool Types entries.

Technical Support
If you have a problem with MRBackup, think you've discovered an
"undocumented feature" or just need help, please call! I'll do my best to
help you get the most out of MRBackup Professional. If you don't have
telecommunications software or a modem, you can write to

 MRsoftware
 348 Indian Avenue
 Portsmouth, RI 02871

 [phone]

MRsoftware maintains an email account on BIX (markr) and a vendor support
forum, amiga.vendors/mrsoftware

Users on either Usenet or Internet can send e-mail to

 [e-mail]


MRsoftware has a customer support BBS where product updates and user
support are provided. The BBS phone number is [phone]. The BBS is
supported by a SupraFAXModem and will answer at 1200, 2400 or 9600 baud
(8N1). The BBS software is AXsh which is a bit different than the typical
BBS system (it's user interface is very much like the Unix operating
system). Presently, two Login prompts must be satisfied to gain access to
the BBS (this will probably change in the near future).

At the first Login prompt, always enter `bbs' (without the quotes).

At the second Login prompt, do one of the following:

 First-time callers must enter `new' to register as a new BBS user,
 then follow instructions as they appear.

 On subsequent calls, enter your BBS user name and password, as you
 chose them during your initial registration.

Do not forget your password! If you lose it, the only way you will be able
to regain access to the BBS is to request a new one (it's encrypted, so
even I don't know what it is!).

A special `guest' account (password = guest) is also provided on the BBS.
This account can be used to test-drive the BBS or to make special requests
such as assigning a new password :-).

The latest shareware distribution archive of MRBackup Professional will
always be available on the BBS in the public download directory. Other
MRsoftware shareware and PD offerings are also available here.

For registered MRBackup Professional users, the latest registered version
of MRBackup Professional is also available.

Limited voice support is available by calling [phone] on weekdays
from 6:00 p.m. to 9:00 p.m. (EST). PLEASE DO NOT CALL AFTER 9:00 p.m.!!!
Voice support is also available on weekends from 9:00 a.m. to 6:00 p.m.
if you're lucky enough to catch me. In addition to MRBackup Professional
development, I also have a `life' which keeps me on the run.

MRBackup Tips
-------------
This section contains bits of information which will help you achieve
maximum satisfaction and performance from MRBackup Professional. If you
have a useful tip, please submit it and we'll incorporate it here.

Improving Throughput
One important factor in the performance of the AmigaDOS filesystems is the
number of disk buffers allocated to each drive. For hard disk drives, this
value can be set when you partition the drive. The value can also be
modified for any drive with the AmigaDOS `AddBuffers' command. There is no
set value that works well for all drives, but I recommend that you use a
value of at least 30 buffers. Bear in mind that using too many buffers can
waste memory and perhaps even slow down filesystem performance.

The number of buffers assigned to a floppy disk drive has no effect on Fast
Disk performance but will have an impact on AmigaDOS backups to floppy
disks.

The `Buffer' parameter in the General Parameters (main) window now has a
minimal effect on overall performance since most buffers used by MRBackup
are actually tuned to the best match between input and output devices.

If you are backing up to SCSI tape, the buffer size that you specify in the
mountlist entry is very important. Most tape hardware has internal buffer
memory. Data is held in this buffer until it fills, then is written to
tape. If you specify a mountlist entry buffer size exactly matched to the
capacity of the tape drive's internal buffer, you will achieve maximum
parallel execution of the tape handler and MRBackup and thus maximum
throughput. This can also be a case where more isn't necessarily better.

AmigaDOS Formatting
When performing AmigaDOS backups to floppy disk, you can control the
formatting of individual diskettes via the `Formatting' and `Filesystem'
settings in the General Parameters window. When `Formatting' is set to
`Normal', MRBackup executes a script named MRBackup:FormatDisk. This
script is designed to run automatically without user assistance or
intervention. However, due to the design of the AmigaDOS Format program,
if a disk error is encountered, the script may not be able to complete. If
you experience this problem, you may want to edit the FormatDisk script to
make it more interactive. Find the line that reads:

SYS:System/Format <nil: Drive {Device} Name {Label} {NOICONS} {QUICK}
{FFS}

and remove the `<nil:' input specification. This will cause the script to
pause until you press the RETURN key. If you're running MRBackup on a
custom (non-WorkBench) screen, you will have to bring the WorkBench screen
to the front and locate the FormatDisk window in order to do this.

I recommend that you preformat all new (out of the box) diskettes, then use
the `Quick' setting in the `Formatting' option. If you're running AmigaDOS
2.04 or beyond, the FormatDisk script will not be used. Instead, MRBackup
can call an internal AmigaDOS support routine to perform the formatting.

Backup Operations
-----------------
The data and programs on your Amiga might well be worth more to you (in
terms of cost to replace) than the machine itself. Hard disks fail.
Systems "crash", causing irrecoverable damage to hard disk partitions.
Backups are insurance against such probabilities. However, they often
don't get done. The excuses are many and varied. "I'm too busy", "I meant
to, but...", "I don't have enough floppy disks", etc. We are all guilty to
varying degrees. Even the author of this backup program has been caught
"with his pants down" on a couple of occaisions (excuse #1). Needless to
say, backups are not a fun way to use your Amiga and they require
discipline to be done on a regular and effective basis. MRBackup goes a
long way toward making this chore more pleasant.

MRBackup preserves all file attributes when backing up and restoring files.
The file protection word (HSPARWED), comment and modification date are all
maintained. This is true for all backup modes.

The Backup Modes
----------------
In a previous section, we touched briefly on the fact that MRBackup
supports three backup modes:

 AmigaDOS Backup Mode

 Fast Disk Backup Mode

 SCSI Tape Backup Mode


MRBackup provides you the flexibility to choose the mode that is best
suited to your needs (or budget!).

AmigaDOS Backup Mode
The AmigaDOS backup mode provides full compatibility with AmigaDOS and its
tool set. That is, you can manipulate the files in an AmigaDOS save-set
with the standard Amiga tools such as DIR, LIST, COPY, TYPE, etc. When
backing up to diskette, MRBackup creates disk volumes which are accessible
to the AmigaDOS filesystem. MRBackup also employs no hardware-specific
"tricks" in this mode. If the disk hardware is supported by standard Amiga
software, MRBackup will handle it (if you find an exception to this, please
let us know!).

One important item to note is that you are not required to backup files to
floppy diskettes. If you are fortunate enough to have a "spare" hard disk,
a hard disk with removable media, lots of extra space or if you are
connected to a network file server, you can use any of these for your
backup destination. You can also perform backups from one directory to
another.

Fast Disk Backup Mode
The Amiga's original filesystem, while providing a great deal of
recoverability, suffers from poor performance. This is especially notable
when accessing floppy disks. This can be overcome somewhat by adding more
disk buffers via the AddBuffers command or by using a floppy disk
accelerator (caching program) such as ASDG's Facc-II. The new, improved
Fast File System (FFS) enhances performance a great deal but is still slow
when working with floppy disks.

MRBackup addresses this problem by providing a new diskette format. This
format is called MRBackup Fast Disk Format (real catchy name, eh?). In a
sense, this format is analagous to a streaming tape drive. Floppy disk
head movement is minimized. The diskette is formatted as data is written
to it and slightly more data can be written to the diskette (without using
any compression techniques). Also, files are automatically split across
volumes in Fast Disk mode, meaning that there is no unused space on your
backup diskettes. At the same time, a high degree of integrity and
recoverability has been designed in. Though this format cannot be read by
the AmigaDOS filesystem(s), you will most likely prefer to use it for most
general-purpose backups because it is so fast.

Another interesting feature of Fast Disk mode is that you can BACKUP TO A
FILE OR ANY STREAM-ORIENTED DEVICE! This capability, in essense, simulates
a very large capacity floppy diskette. You can then manage this backup
file as a single entity. If you're fortunate enough to be connected to a
networked file server with lots of available disk space, the advantages are
tremendous! You can perform a full backup without changing disks, saving
your backups in remote files while fully preserving the AmigaDOS attributes
of the original files.

SCSI Tape Backup Mode
As you might have guessed, this mode supports a streaming tape drive with a
SCSI (Small Computer Systems Interface) interface. It is essentially the
same as Fast Disk mode, except that additional support and modified
error-handling behavior are invoked for the tape drive. Refer to the
section titled @{ "MRBackup SCSI Tape Support" ALink
"MRBackup:Help/MRB_SCSITape.guide/main" } for specific information.

You may not have even thought of it, but there are several approaches to
backing up your system. Each has its advantages and disadvantages. You
may use one or more of them, depending upon your use of the Amiga.
MRBackup is so flexible that you may come up with several other approaches
not detailed here.

Backup Schemes
--------------

The Full Backup
A full backup is the most desirable method if time and available backup
media are not limiting factors. A complete "snapshot" of your hard disk
partition(s) is taken, fully reflecting the state of your machine at that
point in time. If you are using floppy disks to backup a large partition,
however, you may find this approach quite burdensome. Given MRBackup's
flexibility, however, you will quite likely find a mix of backup techniques
that satisfy your needs.

Another thing to remember is that much of your commercial software already
has a backup - the original disk (or the backup you made of the original
disk if you followed typical vendor's instructions). If you have lots of
commercial software installed on your hard disk, you should probably
consider excluding the files which don't change (programs, examples, etc.)
via the backup filter. This will dramatically cut down on the time and
media required for a "full" backup.

The Incremental Backup
Incremental backups provide a reasonable alternative to the full backup if
the proper procedures are followed. The incremental backup consists of a
full system backup followed by one or more partial backups. The partial
backups record only the files that have changed since the full backup was
performed.

Incremental Backup Based On File Modification Date
Each time a file is written (modified), the AmigaDOS filesystem sets the
file's modification date to the current date and time, as set in the
Amiga's time-of-day clock. MRBackup can take advantage of this fact by
comparing file modification dates against the Test Date setting in the main
window. Only files changed on or after the Test Date are selected for
backup.

A typical backup scenario for a date-sensitive backup might be:

 · Perform a full system backup to backup media set 1.

 · Perform incremental backup to backup media set 2.

 · Perform incremental backup to backup media set "n".

 · Repeat the sequence starting with step 1.

In the sequence above, there is an implied delay between steps. Depending
upon your requirements and confidence level (degree of self-discipline?),
the delay may range from several hours to a week or more (not much more!).
You might choose a one month cycle (i.e. step 1 is repeated on the first
Saturday of each month). Notice that multiple media sets (tapes, floppies,
files, etc.) are required. When performing incremental backups, you must
not destroy your previous save-set(s).

There is some room for variation here, however. You might want to maintain
just two sets of backup media. The first set would contain the full
backup, while the second set would contain all files which changed since
the full backup was done. In this case, each time you perform the
incremental backup, more backup media will be required to hold the
additional files, assuming a dynamic system where files are being changed
on a daily basis.

Incremental Backup Based on Archive Bit Setting
In addition to maintaining the file modification date, AmigaDOS also
maintains an archive indicator bit in each file protection word.
Specifically, AmigaDOS clears the archive bit whenever a file is modified.
Backup software, such as MRBackup, can set this bit when a file has been
successfully backed up. When the Test Archive Bits gadget is set to ON,
only files with cleared archive bits will be backed up. If the Set Archive
Bits gadget is also on, MRBackup will set the archive bits of all files
which have been backed up.

The sequence to observe when performing the archive bit backup is similar
to that used for the date sensitive backup. However, you MUST use a
different set of backup media for each unique step.

As an aside, MRBackup does not prevent you from doing a backup which
combines date testing with archive bit testing. However, it is advised
that you choose one method or the other for desirable results.

The Project Backup
If you're a developer, you may be concentrating all of your work in a
specific directory hierarchy. Likewise, if you're a graphics artist, you
may have a specific area in which you work. In these instances, it is
recommended that you do daily "full" backups of these selected areas. This
can be accomplished by setting the Home Path to the name of the topmost
directory for the project area and setting the Test Date gadget to January
1, 1978 and setting the Test Archive Bits gadget to "No".

Also, you may wish to define specific backup and compression filters for
each special project area.

The Backup Process
Once you're sure that all save-settings are correct, you may begin the
backup process. This is done by selecting the Backup command from the
Project menu or by typing the keyboard shortcut, Right-Amiga + B.
MRBackup's main window will disappear and a smaller Status Display window
will appear. This window informs you of the progress of the backup. As
the backup proceeds, pop-up requesters will instruct you to insert/remove
media as necessary as well as alert you to other bits of information, error
conditions, etc.

The first backup step performed is a scan of all files specified by the
Home Path. While MRBackup is scanning, the Current File or Directory
gadget in the Status Display window will display the name of the directory
being scanned. Once the scan is complete, MRBackup will present its file
selector. The file selector displays the list of files that were
considered eligible for backup, according to the backup parameters you have
chosen. It then gives you the option to omit certain files (or groups of
files) from this list. See the section entitled @{" The MRBackup File
Selector " ALink "MRBackup:Help/MRB_FileSelector.guide/main" } for details
on its operation.

Assuming that you completed the file selection process by clicking the OK
button in the file selector window, MRBackup will proceed to backup your
files. If you have selected either AmigaDOS or Fast Disk backup mode, you
will be prompted to insert/remove diskettes as MRBackup requires your
assistance. MRBackup does not currently provide support for the Amiga
Floppy Disk Carousel since, according to our knowledge, it doesn't exist!

When the backup is complete, make a quick check of the Errors gadget in the
Status Display window. If it is non-zero, it would be a good idea to check
the backup log to determine the nature of the errors before assuming that
the save-set is acceptible.

The MRBackup Compressor
-----------------------
The compressor is a free-running application typically started by MRBackup
to perform data compression/decompression services. When MRBackup requires
these services, it enters into a "dialogue" with the Compressor. By
separating the compression services from the MRBackup program, the MRBackup
program is smaller. Compression performance is also enhanced by the
streaming of data to/from the compressor (actual data movement is
minimized).

The compressor is implemented as a small overlayed program. Upon startup,
it first checks to see if a copy of Compressor is already running. If so,
it exits immediately (only one instance of Compressor may be run at one
time). Otherwise, it creates a public port named "MRCompress". When it is
idle, very little memory resources are required. When it becomes active,
the primary code segment is "rolled in" and memory is allocated for the
compression/decompression tables.

The compressor should normally be kept in the same directory where the
MRBackup program is stored. The logical name "MRBackup:" should point to
this directory. If you wish to preload the compressor so that MRBackup
will always find it available, simply issue the following command, either
from the CLI or from your s:user-startup script:

 RUN <nil: >nil: MRBackup:Compressor

If you wish to stop the compressor, just issue the following command from
the CLI:

 MRBackup:Compressor quit

The following compressor executables are provided:

 · Compressor
 Compressor with overlays, will run on any Amiga

 · Compressor.No_Overlays
 Compressor without overlays, will run on any Amiga

 · Compressor_020
 Compressor with overlays, optimized for accelerated Amigas

 · Compressor_020.No_Overlays
 Compressor without overlays, optimized for accelerated Amigas

The overlayed configuration requires very little memory when it is idle
since the compression code segment is removed from memory. This is
normally the preferred version to use. However, this also means that the
Compressor program file must be readily accessible so that the overlay
segments can be accessed quickly. If you are in a situation where you must
run MRBackup from floppy disk, you may prefer to use the non-overlayed
version. To do this, simply rename the overlayed version to
"Compressor.Overlays" and rename the non-overlayed version to "Compressor".
DO NOT attempt to run the 020 versions of the Compressor on a stock 68000
machine. These versions contain instruction codes not supported by the
68000 processor. Attempting to run them will crash your system.

Compression guide
-----------------
Data Compression

MRBackup provides you with the ability to compress your files as they are
written to a save-set and to decompress them when they are restored. The
primary motivation for doing this is to save space on the backup media and
thus reduce the amount of media required to hold the saveset. There is a
performance penalty exacted for this, however. You must determine if the
savings in space are worth the extra time required to perform the backup or
restore of compressed files. The use of data compression also places extra
demands on system memory which may be a consideration if you are running
other programs (multitasking) while MRBackup is running.

Data Compression Method
MRBackup employs Lempel-Ziv compression. While this method does not yield
the highest compression ratios, it is one of the faster software
compression algorithms available. Its ability to be "tuned" through the
use of user-specified code size limits allows you to make certain
performance trade-offs. Larger code sizes will make greater temporary
demands on system memory but will result in higher compression ratios.

When a file is compressed, special codes are written at the beginning of
the compressed file to indicate that it is compressed and to record the
size of the codes used for compression. Thus, you need not remember what
code size was used to compress a particular file when you later decompress
it.

The Compressor
--------------
MRBackup performs data compression with a separate program named
Compressor. Whenever you start a backup with compression enabled or a
restore with decompression enabled or if you compress/decompress individual
files using the Utilities, MRBackup will check to see if the Compressor is
running. If not, you will be asked for permission to start it. MRBackup
will then enter into a "conversation" with the Compressor, requesting data
to be processed and retrieving the results.

There are several advantages to this approach. Some of them are too
technical to be discussed here. Of most importance to the user is that as
a result, the MRBackup program is smaller. If data compression is not
being used, less memory is being used by MRBackup. The Compressor program
is designed to employ "overlays". When it is idle, it uses almost no Amiga
resources since it releases the data compression code and buffer memory and
waits for the next request to do something.

Starting and Stopping the Compressor Manually

You may elect to start and stop the Compressor "manually" if you so desire.
To start the Compressor, simply enter

 RUN MRBackup:Compressor <nil: >nil:

from the Shell command prompt or double-click the Compressor icon. To stop
the Compressor, enter

 MRBackup:Compressor quit

from the Shell command prompt.

Compression Estimating
Compression estimating allows MRBackup to better determine if a file will
fit on the current backup diskette when performing an AmigaDOS backup with
compression enabled (it is irrelevant to Fast Disk and SCSI Tape backups).
MRBackup does not know in advance what a file's size will be after it is
compressed. Therefore, when determining whether a file will fit on the
current backup diskette, the file's full size is used. This can result in
a significant amount of wasted space on each diskette. If you set the
compression estimate to a non-zero value, MRBackup will apply this estimate
when determining space available. A reasonable value to start with is 35
(%). This means that you expect most files to be 65% of their original
size (100%-35%) when compressed. Please note that this may lead to
occaisional "disk full" errors, depending on how aggressive your estimate
is. In this case, MRBackup will delete the partially copied file and force
a new diskette. This is a feature you'll have to develop a "feel" for. Of
course, you can always play "safe" and leave this value at zero.

The MRBackup File Selector
-------------------------
The file selector is presented to you during backup and restore operations
to enable you to "fine tune" the list of selected files. Before we discuss
its operation, let's take a quick look at the graphical objects that make
up the file selector. In the discussion that follows the term entry refers
to both files and directories.

The files available for selection/deselection are presented in the large
box at the left of the file selector. Just to the right of this box, you
will see a scroll bar. When there are more files at a given level than can
be viewed in the selection box, the drag bar (rectangle within the scroll
bar) will be sized in proportion to the number of visible vs. total
entries. You may click and drag this bar to reveal other entries at the
current level. You may also scroll the list one item at a time by clicking
on either of the small buttons at the bottom which have arrow indicators on
them.

Each time you click on an entry in the list, it will toggle between
selected and deselected. An entry in the selected state is highlighted by
a dark background. Directory entries and file entries are represented by
different colors. To view the contents of directories (and their
subdirectories), position the mouse pointer over a directory entry and
double-click (two clicks, in rapid succession) on the entry. The display
box will be redrawn with the contents of that directory and the Current
Level indicator will be incremented. To return to the previous level,
simply click on the Up button.

Current Level
This gadget reports the nesting level of the directory you are currently
viewing. The top level is zero.

Up

When you click the Up gadget, the next higher directory level is displayed
and the Current Level gadget is updated accordingly.

Include Pattern
This is a string gadget which works in conjunction with any of the Select
buttons (later). The Include Pattern is a filename matching pattern (as
used in the MRBackup filters) which is applied to each filename when one of
the Select buttons is clicked. Only those names matching the pattern will
be selected. If the Include Pattern is blank, no include matching is
performed.

Exclude Pattern
This is a string gadget which works in conjunction with any of the Select
buttons (later). The Exclude Pattern is very similar to the Include
Pattern, except that filenames matching the pattern will be excluded from
selection when a Select button is clicked. If both Include and Exclude
patterns are specified, the Include pattern is applied first.

Select All
When the Select All button is clicked, all files in the selector file list
are selected.

Select all, this level and below
This button causes all entries at the current level and lower (higher level
numbers) to be selected.

Select all, this level only
This button causes all entries at the current level to be selected.

Deselect all
This button has slightly different behavior, depending upon the Current
Level setting. When the Current Level is zero (top level), all entries are
deselected. When the Current Level is non-zero, all file and directory
entries except the parent directories for the current level are deselected.

Deselect all, this level and below
This button causes all entries at and below the Current Level to be
deselected.

Deselect all, this level only
This button causes all entries at the Current Level to be deselected.

Entries
This gadget reports the total number of entries (files and directories)
contained in the file selector list.

No. Selected
This gadget reports the total number of entries currently selected.

Disk Est.
For backup operations, this gadget provides a rough estimate of the number
of disks required to hold the files currently selected. If file
compression is enabled, the Compression Estimate value (entered by you) is
factored into the disk estimate. The disk estimate value is meaningless
for restore operations.

OK
Click this button when your file selection is complete and you wish to
proceed with the current operation (backup or restore).

CANCEL
Click this button when you wish to terminate the current operation (backup
or restore).

Current Directory (unlabeled)
The long gadget at the bottom of the file selector window displays the full
name of the current directory. It is empty when the Current Level is zero.

General Parameters Window
The General Parameters Window contains parameters common to most MRBackup
operations. In addition to the usual string gadgets and command buttons,
you will also notice several square buttons (raised gadgets), labeled with
a question mark (?). These are file requester gadgets. Each of these is
associated with another gadget which specifies a device, directory or file
name. When you click on a file requester gadget, a file requester window
is superimposed on MRBackup's main window . With it, you can navigate your
file system and easily select the appropriate name for the corresponding
gadget.

The following paragraphs describe all of the gadgets in the General
Parameters window. Please take the time to read this information
carefully, as several important key concepts are presented here.

Preferences Gadget
This gadget names the file where MRBackup's operating parameters (user
preferences) are stored. If MRBackup is started without an explicit
"initial file" specification (-i option from CLI, INIT=<name> tool types
from WorkBench), the current directory is searched for "MRBackup.init". If
the file is not found there, the working directory (default =
MRBackup:Prefs) is searched. You may change MRBackup's parameters
(including this one), then use Save Preferences to record your new
settings. You may also reinitialize MRBackup with another preferences file
by changing this specification.

Home Path Gadget
The Home Path describes the device or directory where your files normally
reside. During backup operations, files are copied from the location
specified by the Home Path. During restore operations, files are copied to
this location. You may type the Home Path value directly into the gadget
box or you may use the file requester to assist you. The Home Path must
specify a device, volume or directory name (not a file name).

Backup Path Gadget
The Backup Path describes the destination (TO path) for files during a
backup or the source (FROM path) for files during a restore. Normally, the
backup path is the name of one of your floppy disk drives. If one or more
of the floppy disk icon gadgets is selected, the Backup Path is ignored.
See the section entitled @{" Backup Operations " ALink
"MRBackup:Help/MRB_Backups.guide/main" } for more details on the Backup
Path.

Floppy Disk Icons
MRBackup supports selection of up to four floppy disk devices (DF0:
through DF3:) for backup or restore. This allows you to preload your disk
drives, reducing the frequency with which you must insert diskettes.
MRBackup will cycle through the selected drives and prompt you for more
diskettes only when all have been used or an error is detected. When you
click on one of these icons, a check-mark will appear, indicating that the
drive is selected. Whenever floppy drives are selected in this fashion,
the Backup Path specification is ignored.

Voice Gadget
This is an ON/OFF button which enables or disables MRBackup's speech
capability.

Media Type Gadget
This gadget selects the type of backup or restore to be performed and
cycles through the following range of values:

 · AmigaDOS
 · Fast Disk
 · SCSI Tape

Note: the media types are described in detail in the section entitled

Buffer Gadget

When MRBackup performs input or output from/to a file, a certain amount of
memory is set aside as a buffer (work area). This is done to minimize the
number of physical disk accesses necessary to move data from/to a file.
The bigger the buffer, the fewer disk accesses that are required to move a
file. The default buffer size is 32K bytes (K = 1024, thus 32K = 32768
bytes). If your system has expanded memory, you can take advantage of it
by increasing your buffer size. The maximum buffer size allowed is 512K.
There is no practical benefit in specifying a buffer which is more than two
times larger than the largest file on your system. This will simply waste
memory which might be needed by other applications (remember - we can
multitask while doing a backup or restore!).

Listing Path Gadget
MRBackup normally generates a listing during backups. This gadget
specifies the file or device to receive the listing. You may type the
listing path directly into the gadget or you may use its requester gadget
to assist you. To send the listing directly to the printer, you would
select "PRT:". To save the listing to a file on the hard disk, simply
select the appropriate directory and file name.

Log File Gadget
MRBackup will optionally generate a log of all of its activities if the Log
File gadget contains a valid pathname. This log will contain time-stamped
progress reports and error messages. To disable the log, simply clear this
gadget. When errors are detected during a backup or restore, it is good
practice to check the contents of the log for the cause and severity of
these errors.

Options Button
This command button activates the Options window and is provided as a
convenient alternative to the equivalent menu command.

Filters Button
This command button activates the Filters window and is provided as a
convenient alternative to the equivalent menu command.

Backup Button
This command button initiates a backup operation and is equivalent to the
Backup menu command.

Restore Button
This command button initiates a restore operation and is equivalent to the
Restore menu command.

Utilities Button
This command button activates MRBackup's file utilities. It is equivalent
to the Utilities menu command.

MRBackup Restores
-----------------
The Restore Process
The file restoration process is the inverse of a backup. You would most
likely do a full restore when rebuilding a disk partition. A partial
restore might be done to recover files which were deleted accidentally.

Restore Operations
------------------
Relevant Settings

The following MRBackup settings come into play when performing a restore
operation:

· Home Path - the target ("to" location) for the restore.

· Backup Path - the source ("from" location) for the restore.

· Disk Selection Icons - optional selection of backup path
 (overrides Backup Path).

· Backup Mode - indicates the type of save-set we are restoring from.

· Decompression - sets the upper code size limit for file decompression.
 Files compressed with code sizes larger than this limit will be
 restored in their compressed state.

· Buffer, specifies the amount of memory to be used for file I/O buffering
 (same as backup).

· Decompression Filter - compressed files whose names match one or more of
 the patterns in this file will not be decompressed during a restore.

· Log File - records errors and progress messages during the restore.

· Error Handling - establishes the type of error handling employed during
 the restore.

· Voice On/Off - enables/disables MRBackup's speech capability.


Points to Remember
------------------
There are some interesting (and important) items to be aware of when
performing a file restore operation. During a backup, MRBackup preserves
the complete directory hierarchy for the files which are backed up . This
may be cause for some confusion. Consider the following example. You
perform a backup with the Home Path set to "DH0:" (your first hard disk
partition). A portion of the files selected might look like

 ARexx
 ARexx/Docs
 ARexx/Examples
 ARexx/Tools
 Docs
 Docs/Amiga
 Docs/Graphics
 Docs/Utilities
 ... etc.

If you later restore the save-set with the Home Path again set to "DH0:",
your files will be restored to the same level in the hierarchy.

When you do a backup and specify a subdirectory as the Home Path, the full
directory hierarchy from the "top" of the partition through all levels
included by the Home Path is preserved. For levels higher than the Home
Path, only the directories are preserved (files are ignored). When you
restore such a backup, the Home Path must be changed to the name of the
partition (e.g. DH0:, DH1:, etc.) to which you want the files recovered.
Of course, if you wish to restore your/save-set to a lower-level hierarchy,
you are free to select any valid Home Path.

It is important to note that MRBackup will not overwrite an existing file
with a file which has the same or earlier modification date unless you
enable the Force Copy option. During the restore, a message will be
displayed to the screen and written to the log file for each file that is
skipped because of this condition.

MRBackup SCSI Tape Support
If you are regularly backing up more than 20MB of data, you really should
consider the purchase of a streaming SCSI tape drive. Chances are, you
already have the requisite SCSI interface controller (to interface and
control your hard disk drive) so you will only need to aquire a tape drive.
SCSI tape drives are becoming more and more affordable, with several good
quality units available in the under $300 price range. Tape cartridges
cost about $20 each. The time and aggravation you'll save are inestimable
in their value. Also, since you'll be much more likely to perform regular
backups with such a painless medium, your system will be much more secure.
Do yourself a favor!

A SCSI tape handler is provided with MRBackup and is installed as a part of
the standard MRBackup installation procedure. To use it, you must perform
the following steps:

· If it isn't already present, copy the MRBackup tape handler,
 MRTape-Handler to the L: directory:

 COPY MRBackup:L/mrtape-handler to L:

· Add the supplied device mountlist entry to your DEVS:Mountlist file,
 using a text editor or, if you are running WorkBench 2.04 or above,
 just copy the mountlist entry file to the DEVS: directory. The
 mountlist entry provided with MRBackup is named "mountlist.mrtape".
 It contains the following:

 MRTAPE: Handler = l:mrtape-handler
 StartUp = "128/scsi.device/4/0/3"
 Stacksize = 4000
 Priority = 5
 GlobVec = -1
 #

You may need to change the "Startup" line. The expression to the right of
the equal sign (=) has the following format:

 "<buffer_size>/<device_driver>/<device_number>/<luno>/<flags>"

The beginning and ending double quotes are required if you are using the
standard AmigaDOS Mount command.

The <buffer_size> parameter is specified in multiples of K (K=1024). The
example value of 128, above, provides double-buffering for the WangTek
model 5XXX-ES tape drives, which have an internal 64K buffer.

The <device_driver> parameter specifies the device driver to be used to
talk to the device. Use "scsi.device" with the CBM A2091 SCSI controller.
Consult your owner's manual if you are using a non-Commodore SCSI
controller. Also, note that this field is case-sensitive. If your device
driver's name has upper case or mixed-case letters in its name, be sure you
specify this field exactly as the driver is named.

The <device_number> parameter specifies the SCSI device number, usually
established by jumpers or DIP switches or jumpers on your tape drive.

The <luno> (logical unit number) field is not currently supported and must
be zero.

The <flags> parameter is a specially encoded value which selects certain
features of the tape drive. Each bit position in the <flags> parameter has
a unique value (1, 2, 4, etc.). Various feature selections can be made by
adding these values together. The current feature values are:

1 - asynchronous mode
2 - use on-board hardware buffering

Thus, to select both asynchronous mode and on-board buffering, you would
add these values together for a <flags> value of 3.

Once the above steps have been performed, you must mount the MRTAPE:
device. This is done with the following command:

 MOUNT MRTAPE: or

 MOUNT MRTAPE: FROM DEVS:mountlist.mrtape (AmigaDOS 2.04)

You may then specify MRTAPE: as your Backup Path. You may also automate
the device mounting process by placing the above command in your
S:Startup-Sequence (or S:StartupII) file.

Special Features of MRTape-Handler
The tape handler provided with MRBackup, MRTape-Handler, is designed to
work with a wide array of tape devices from many different vendors. Though
you many not redistribute this handler, you are welcome to use it with
other Amiga applications. When used with MRBackup, MRTape-Handler can
communicate certain information to MRBackup which will allow dynamic tuning
of the buffers used to transfer data between the two processes.

Asynchronous vs. Synchronous Mode
MRTape-Handler supports both synchronous and asynchronous tape access. In
synchronous mode, the program requesting a tape operation must wait until
that operation completes before it can continue. In asynchronous mode,
MRTape-Handler will attempt to complete the operation "on its own time", in
parallel with the requesting program's activity. Thus, asynchronous mode
generally yields better performance. However, we do not live in a perfect
world. Certain combinations of tape drive and SCSI controller can lock up
(hang) the Amiga when run in asynchronous mode. We have yet to see a
definitive solution to the problem though many hardware "hacks" have been
offered. Synchronous mode seems to fare better in these situations.

Multiple Savesets on One Tape
MRTape-Handler has the ability to "stack" multiple savesets on a single
tape cartridge. This is achieved by a slight modification to the device
naming conventions used by the MRTape-Handler. Normally, when you specify
the tape device name as "MRTape:", the tape is rewound prior to the start
of the backup and any information previously written to the tape is
overwritten. To append a new saveset to the end of a tape cartridge which
already contains one or more savesets, simply append an "A" to the tape
device name (e.g. "MRTape:A"). Prior to writing the new saveset, the tape
is positioned past the end of the last saveset on the tape.

To restore from a saveset which is not the first saveset on the tape, you
must append the saveset number to the tape device name. Saveset numbers
begin with zero. Therefore, to retrieve the third saveset, you must append
a "2" to the tape device name. Example: "MRTape:2". The only "trick" to
all of this is to remember the order of your savesets. MRBackup currently
doesn't provide any means to record this information. Thus, you should
keep this information in a notebook or in a text file on your system.
Should you forget, however, this information is very easily retrieved with
MRBackup's Scan Tape command. Improvements on this capability are planned
for a future release of MRBackup Professional. You should also be aware
that this capability only exists for "sequential access" tape drives such
as the Tandberg, WangTek, Sony, etc. This is because MRBackup depends upon
tape marks to separate its savesets. Drives which employ "direct access",
such as the 3M drive, will not support this feature.

Using MRBackup with Other Handlers
The decision to use a tape handler, rather than embedding tape-specific
code in MRBackup was an important one. Though there may be a minor penalty
in performance, the net result is that MRBackup is adaptable to other
third-party handlers (public domain, shareware or commercial) which may be
developed for specific devices suitable for backups. If the tape handler
supplied with MRBackup Professional doesn't appear to be performing
optimally with your particular device, don't hesitate to try another
handler which you suspect might work better. Of course, we would be very
grateful for any information you pass back to us with regard to any
problems you might encounter. We are constantly striving to improve the
quality of MRBackup Professional.

MRTape: SCSI Tape Handler V1.07
This is a tape handler designed primarily for MRBackup Professional.
Portions of this handler were originally derived from code written by
Markus Wandel and Bob Rethemeyer. I am very grateful to them for their
contributions to my understanding of SCSI tape operations.

The current version of mrtape-handler represents a complete rewrite of the
earlier code and sports many new features, several of which were designed
specifically to support MRBackup Professional. It is known to support the
following SCSI tape drives:

 Wangtek 5XXX ES
 This drive has an on-board 64K byte cache. Specify "64" as the
 buffer size if you can afford it (this results in 128k bytes
 being set aside by the handler, so plan accordingly). I believe
 you'll get optimal results with MRBackup if you also set "his"
 buffer size to 64K. This results in an optimal double-buffering
 arrangement.

 Data Cartridge Technology MCD-40 (and -20)
 This drive uses a fixed-size block of 8192 bytes. Specify "8" as
 the buffer size in your mountlist entry. This drive does not seem
 to provide any reasonable asynchronous behavior. I was quite
 disappointed with its performance compared to the Wangtek or the
 Sony.

 Archive ????

 Sony SDT-1000 (added 03/30/91)
 On the SONY DAT drive, it is currently assumed that the drive
 defaults to "variable block size" mode. Since this is the
 vendor-preferred mode, MRBackup uses it. The drive is a real
 performer, though settling time after a rewind is a bit
 unsettling. :-)

 Tandberg 3600 series
 This is quite similar to the WangTek drive. It has an on-board
 64K byte cache, though only 60K is really available for buffering.
 This one may have a few glitches when run in asynchronous mode.


The use of the word "handler" is significant. This is not a "device
driver". It responds to AmigaDOS I/O packets. Implementing tape support
in this way (as opposed to embedding SCSI direct calls within the MRBackup
Professional program) provides a large degree of device independence for
MRBackup Professional. MRBackup Pro simply writes a stream of data
(encoded in MRBackup's "FastDisk" format) to the Backup Path. This may
just as easily be the SER: device, a file (local or networked) or some
other device configured to respond to standard filesystem calls.

Here are the packets supported and the degree to which they are supported:

 ACTION_FINDINPUT
 Opens the drive for exclusive read access only.

 ACTION_FINDOUTPUT
 Opens the drive for exclusive write access only.

 ACTION_INFO (26)
 ACTION_DISK_INFO
 These fill in an InfoData structure with as much useful information
 as possible. Specifically, an attempt is made to fill in the
 following fields:

 id_DiskState
 If a tape is inserted, this field is set to ID_UNREADABLE_DISK.
 If no tape is inserted, this field is set to ID_NO_DISK_PRESENT.

 id_NumBlocks
 An approximation of the tape cartridge capacity is provided.

 id_BytesPerBlock
 If a 3M drive (MCD-40) is detected, 8192 is assumed. Otherwise,
 512 is assumed.

 id_DiskType
 This field is set to 'TAPE'. The first 4 characters of the
 manufacturer's code might be used in a later revision.

 id_InUse
 This field is set to the boolean equivalent of "tape cartridge
 inserted".

 ACTION_LOCATE_OBJECT (Lock)
 A rather hokey lock is created and returned. It should be sufficient
 for programs which require such things.

 ACTION_EXAMINE_OBJECT (Examine)
 This packet is recognized, but ERROR_OBJECT_WRONG_TYPE is currently
 returned.

 ACTION_READ
 Just what you'd expect.

 ACTION_WRITE
 Just what you'd expect.

 ACTION_END (Close)
 If the write buffer has any residue, it is padded to the device block
 size with zeros and written to the drive. If the drive is not the
 3M variety, a filemark is then written. The device is then marked
 as closed.

 ACTION_DIE
 All resources allocated to the handler are released and the handler
 is unloaded from memory. If you replace the current handler code
 with a new version and then re-access the drive, the new code will
 be loaded and initialized (great for development - no need to
 reboot).

(There are others, to be documented later.)
MRBackup currently treats the backup set as one contiguous file.
Individual files have special header blocks and the data blocks have
control information which defines the end of each file. There is a special
control block to mark the end of tape. Thus, the filemark isn't typically
ever "read" and isn't required, which is how the 3M drive
(block-structured) is able to work.

MRTape-Handler uses asynchronous I/O, but you might not believe it when you
use the 3M tape drive. I'm not sure what the problem is, but I wasn't able
to get good performance from the 3 1/2" ministreamer that I tested with.

The buffer size parameter in the Startup field of the mountlist entry must
be chosen with care. This is the size of 1 buffer (as opposed to 1 block,
as is typically specified for filesystems). The handler allocates one
buffer for synchronous I/O and two buffers when using asynchronous I/O.
For example, I reccommend 8 (8192 bytes) for the 3M drive (this is required
by the drive) and 64 (65536 bytes) for the Wangtek 5150 ES. The Wangtek
has a 64K cache buffer. Setting MRTapeHandler to use 64K buffers causes
128K bytes to be allocated (a significant chunk!) but performance is quite
good. To obtain the best performance for other drives, you may need to
experiment. Use MRBackup Professional's "Throughput" measurement as a
relative guide to the effects that changes in buffer sizes have on your
backups.

Here is a sample mountlist entry for MRTape-Handler:

 This is a mountlist entry for the SCSI tape handler provided with
 MRBackup. Pay particular attention to the StartUp message. Its
 format is:
 "<buffer_size>/<device_name>/<unit>/<luno>/<flags>"

 where
 <buffer_size> is the total amount of buffer memory, specified
 in K (K = 1024);

 <device_name> is the SCSI device driver name;

 <unit> is the SCSI unit number;

 <luno> is the SCSI logical unit number (not currently used but
 must be set to zero);

 <flags> is a set of bits controlling certain tape drive options
 The bit values, which may be added together are:

 1 asynchronous mode, 0 = synchronous mode
 2 use on-board buffer, 0 = don't use on-board buffer

 Example: to enable async mode and the on-board buffer, the
 <flags> value would be 3 (1 + 2).

 Other flag bits will be provided as new features are added.

MRTAPE: Handler = l:mrtape-handler
  StartUp = "64/scsi.device/4/0/3"
  Stacksize = 4000
  Priority = 10
  GlobVec = -1
#


To determine the version number of MRTapeHandler, view the handler with any
binary file editor and look for a string that begins with the letters
"$VER:". You may also use the "version" command under WorkBench 2.0.

A small program, named "die", has been supplied with the handler. It
allows you to force the handler to free up all resources and unload itself.
Example:

 die mrtape:


For a long time, MRBackup has relied on arp.library for many of its
services. The Amiga Resource Project (ARP) was created by Microsmiths,
Inc. of Cambridge, MA. Currently MRBackup only depends upon this library
for file requester (under AmigaDOS 1.3) and date management services and is
being phased out of MRBackup Professional.

MRTape-Handler got its early inspiration from a public domain tape handler
written by Marcus Wandel. Though MRTape-Handler bears very little
resemblence to that code, I am nonetheless grateful to Marcus for sharing
his code which served as an excellent example of SCSI-Direct programming.