SAVRES 7.3d Users' Guide ======================== Authors: C E Chew & C G Wilson Date: 31st August 1988 SAVRES has been upgraded to allow the SC cartridge tape to stream under TSX-plus. Several bugs have been repaired. Extensions to SAVRES have been made to allow it to cope with files as well as devices, and to make it (slightly) easier to cope with multiple files on the one tape. SAVRES is the normal version of this backup programme. SAVREX is the equivalent, assembled and linked for the RT-11 XM monitor. Except where specifically stated in this document, if you are using the XM monitor you may read SAVREX for SAVRES. [It is no advantage to use SAVREX under TSX-plus.] ************************************************ Note that to use the sequential verification of a string of files on a tape as documented in chapter 3, you must have the SC handler provided with version 7.2 or later. A bug in previous versions will allow reading only alternate files from a tape without rewinding it beween files. ************************************************ SAVRES V7.3 Users' Guide Page 2 Incompatibilities with previous SAVRES Versions 7.3: The technique of causing MS: to stream by calling it MS1: has been removed. To cause MS: to try to stream (or any other tape unit which recognizes the special SPFUN request to cause it to try to stream), append "/F" (for FAST mode) to the filename. For example: From? DU: To? MS:DUFILE.DSK/F SAVRES V7.3 Users' Guide Page 3 Update History (from V7) Distribution kit for SAVRES V7.3d (31-Aug-88) SAVRES.DOC no longer included in distribution kit: insufficient room on RS02 floppies. Therefore merely provide SAVRES.RNO and let the user make his own .DOC - sorry! Updates V7.3 to V7.3d - Tidy error messages; fix bugs in error messages - Add .FETCH before rewind/unload - Fix bug (CLOSE mag tape rather than PURGE) - Fix bug in MS: streaming code Updates V7.1 to V7.3 - Put in /F - fast streaming - switch; if used, try using SPFUN -9 on the handler. - Put in /V - verify after save or restore without asking, if only the one volume used. - Put in facility to test whether tape is properly loaded to cope with odd MS problem. Since this uses a rewind and asks questions if this prangs, it is not able to be used with /N or /E. Put version message out if he types a blank line at "From?" rather than all the bloody time. Updates V7 to V7.1: - ability to specify disc files for save/restore/verify with tapes; - ability to control rewinding of tapes to allow easier use of multiple files on one tape. - warning if tape is not correctly loaded - bug fix in SC handler to allow this to work. SAVRES V7.3 Users' Guide Page 4 TABLE OF CONTENTS ----------------- 1 Ideas Behind SAVRES 2 Using SAVRES 2.1 Save, Restore or Verify? 2.1.1 Tape Load Check 2.2 Filenames 2.3 Saving 2.3.1 Saving Complete (Physical) Discs 2.3.1.1 Old Technique 2.3.1.2 New Technique 2.3.2 Saving Device Units 2.3.3 Saving Files 2.3.4 Multivolume Tape Sets 2.4 Verification of Disc Images 2.5 Restoring Disc Images 2.6 Running SAVRES from Bootable Tapes 3 Switches in SAVRES 3.1 Multiple Files & Rewind Control (/N, /E, & /S) 3.2 Rewinding Only (/R & /U) 3.3 Physical Device I/O (/P) 3.4 Fast Tape Streaming (/F) 3.5 Discussion on Rewinds 3.6 Example of Saving & Verifying 6 Files 3.7 Details for Command Files 4 Restrictions 4.1 Tape Streaming 4.1.1 Streaming under TSX-plus 4.1.2 Tape Streaming during Verification 4.1.3 Cartridge Tape (SC) Restrictions 4.1.4 Magtape (MS1) Streaming 4.2 XM Monitor Restrictions 4.3 GPMI Restrictions 4.4 General Restrictions 5 Update Comments 5.1 Improvements on SAVRES 4.2b 5.2 Changes from V6 to V7 5.3 Changes from V7 to V7.2 5.4 Changes from V7.2 to V7.3 6 Streaming Tape Information 7 Distribution and Assembly 7.1 Distribution 7.2 Assembly 7.3 SCNEW handler for TSX-plus and RT-11 Index CHAPTER 1 Ideas Behind SAVRES SAVRES is designed to be a reasonably fast programme to backup and restore discs to and from magnetic tape. It was originally written for the Webster streaming tape cartridge (SC:), but has been extended to accommodate other magnetic tape units. It is capable of saving complete physical MSCP (DU type) discs despite the fact that these must be spread across up to 8 RT-11 logical disc units. The SC cartridge has some features which are inconsistent with other magnetic tape units. The most difficult of these is its inability to backspace. This leads to a requirement within SAVRES that cartridge tapes must be initialized using a special programme (SCINIT) if the user wishes to save more than one file or device upon that cartridge. (See below for further details.) CHAPTER 2 Using SAVRES 2.1 Save, Restore or Verify? SAVRES should be run from RT-11 using the following command: .R SAVRES The user is then guided by prompts, to which he may type a question mark at any stage for further helpful information. The user's answers to the initial two prompts from SAVRES control what action will be taken. These prompts are "From?" and "To?". To save on to tape: From? - reply with disc unit or file to be saved To? - reply with tape unit or filename for output To restore from a tape: From? - reply with tape unit or file containing data To? - reply with disc unit or filename to be restored with that data You will then be asked if you wish to restore or if you wish to verify. The verify question comes first - answer "N" and you will be asked if you wish to restore. To verify disc against tape: From? - reply with tape unit or file containing data To? - reply with disc unit or filename to be restored with that data You will then be asked if you wish to restore or if you wish to verify. The verify question comes first - answer "Y". SAVRES V7.3 Users' Guide Page 2-2 Using SAVRES 2.1.1 Tape Load Check Unless the user suppresses the rewind, the tape will be rewound before use. Should that rewind fail, SAVRES will assume that the tape has not been correctly loaded, and will ask the user to check this. It will then provide the opportunity for him to try again. [The reply to this message is read with TTYINs rather than a GTLIN so that it will not affect operation under command files.] 2.2 Filenames If a filename is specified for the tape device, that filename will be used for the tape but not used as a default for the disc device. If no filename is specified for the disc device, the default filename for the tape device is SAVRES.FIL. If a filename is specified for the disc device, that filename becomes the default filename for the tape device. Thus, saving DU: onto MS: writes to MS using the default name MS:SAVRES.FIL. Restoring MS: onto DU: causes SAVRES to look for the file on MS: called MS:SAVRES.FIL. Saving DU: onto MS:SYSTEM.86 causes the whole of the device unit DU: to be written to MS: as the file MS:SYSTEM.86. On restoring DU: using MS:SYSTEM.86 the whole device unit will be restored from that file (ie SAVRES will not try to write a file DU:SYSTEM.86 unless specifically requested). Saving DU:TSX.DSK onto SC:TSX.DIS uses the filenames as supplied. Saving DU:TSX.DSK onto SC: will write the file SC:TSX.DSK. Restoring (or verifying) from SC: to DU:TSX.DSK will similarly use the filename SC:TSX. [If you have a backup tape written by a previous version of SAVRES and you wish to verify it, you may need to remember the default SAVRES.FIL filename produced by versions of SAVRES without the filename capability.] On the streaming tape cartridge SC:, if a tape overwrite is requested, a dummy file called $$$$$$.$$$ will precede the data file on the tape. This is a safety precaution on SC: tapes - see below. For saving multiple files or devices using SAVRES, see the later chapter concerning control of rewinds. 2.3 Saving After the "From?" and "To?" prompts have been answered, further questions are put to the user: SAVE a Disc (filename) onto SAVRES V7.3 Users' Guide Page 2-3 Using SAVRES Are you SURE [Y/N]? Here the user is told the full names of the input and output files so he may check that everything is as desired. When "Y" is answered to this, he is asked Overwrite the data on the output tape (or cartridge)[Y/N]? If the answer to this is "N", the file produced on the tape by this save will be put after any other files already present on this tape. This is used when it is desired to keep all information already on the tape. It may also be used when the tape has been freshly initialized, by use of the monitor INIT command for normal 1/2" magnetic tapes, or the SCINIT programme for cartridges. The answer "Y" is used mainly in situations where one tape is used repeatedly for backing up one device or file - for example where daily backup of a database is carried out on a set of several tapes, one for each day. On overwriting, the tape is rewound and re-initialized in a manner similar to the INIT command (but NOT as per SCINIT - see below). Then a dummy file called "$$$$$$.$$$" is written on the tape, the tape rewound, and that dummy file read and checked to make sure what is read is what was written. Following this, the data is saved as per the user's request. [Technical note concerning Overwriting] On a cartridge tape the logical end of tape is detected by the presence of one file mark followed by unwritten tape, unlike the two contiguous file marks on 1/2" tape. The tape is only erased either by SCINIT, or on the complete first pass (the first 10000 blocks or so) of writing on to the cartridge. Thus it could be possible, if a file of less than 10000 blocks were overwritten onto a cartridge which had not been previously erased, that the logical end of tape could become confused or unable to be found. This is the reason that SAVRES checks for the "$$$$$$.$$$" file, and, if it is present, will not allow a user to append files to that tape. [This can be done - at your own risk - with the switches available in V7.2 of SAVRES. It does nothing useful however, merely appearing to do so!] 2.3.1 Saving Complete (Physical) Discs SAVRES has the ability to save complete physical disc units if these are MSCP (DU type) discs. SAVRES V7.3 Users' Guide Page 2-4 Using SAVRES 2.3.1.1 Old Technique - To save a large disc onto tape, the user must ensure that the handler has the following set options in effect (substitute DA for DU for second MSCP controller): UNLOAD DU SET DU1 UNIT=0,PART=1 SET DU2 UNIT=0,PART=2 SET DU3 UNIT=0,PART=3 SET DU4 UNIT=0,PART=4 SET DU5 UNIT=0,PART=5 SET DU6 UNIT=0,PART=6 SET DU7 UNIT=0,PART=7 LOAD DU Note that if the disc is the system disc, the system must be re-booted after setting the above partitions, for the options to take effect. If these set options are not in effect SAVRES will not allow the disc to be used in its entirety. To save a large disc the user must append the suffix "A" to the name of the device. Thus to save the DU disc in its entirety the user should specify "DUA:" in response to the "From?" prompt issued by SAVRES. In a similar fashion, to restore the DU disc in its entirety, the user should specify "DUA:" in response to the "To?" prompt issued by SAVRES. (Note that it is thus unwise to use an assigned device name of three letters ending in "A". Of such is the kingdom of computing. Note also that each of the device units is accessed separately. Thus, if you are specifying DUA:, you could get some most odd results if DU, DU0, DU1, ..., DU7 are not ALL units of the same device, preferably unassigned.) 2.3.1.2 New Technique - The Webster DUCM DU handler has the ability to read and write complete physical discs. Whilst there is provision for up to a 32-bit block number, SAVRES is currently restricted to a 20-bit block number - ie devices up to 524 megabytes. To specify that physical I/O is desired, append the "/P" switch to the particular disc unit which corresponds to partition zero of the physical disc you wish to access. For example, if you have two drives on a single controller, and DU0: is partition 0, unit 0 DU1: is partition 1, unit 0 DU2: is partition 2, unit 0 DU4: is partition 3, unit 0 DU5: is partition 0, unit 1 DU6: is partition 1, unit 1 DU7: is partition 2, unit 1 SAVRES V7.3 Users' Guide Page 2-5 Using SAVRES DU8: is partition 3, unit 1 Then unit 0 may be saved, restored, or verified by specifying "DU0:/P", and unit 1 may be similarly accessed by specifying "DU5:/P". Should the user specify a device unit which does not correspond to partition zero of a particular physical unit, an error message will be typed. This technique is impervious to odd assignments. If however a filename is specified with the device name, the "/P" will be ignored. Under TSX-plus this may actually be faster than using the old technique, as the I/O requests are SPFUNs and are therefore not intercepted by the caching system. 2.3.2 Saving Device Units To save a device unit (eg DM0:) merely use the name of that device (without any filename) as the name of the desired input device for SAVRES (at the "From?" prompt). Before version 7.1 of SAVRES, there was only provision for a device name ______ to be used to tell SAVRES what the user wished to save. Thus logical subdiscs had to be used. This is still valid - for example: To save the file DU1:RPL6P.DSK onto tape, you may use the following command: .MOUNT LD DU1:RPL6P then use "LD:" as the input device. [Unfortunately under TSX-plus the MOUNT command presumes caching of the desired file. You may need to set caching to zero as it seriously degrades the speed performance of SAVRES, or use the WA disc-partitioning handler.] 2.3.3 Saving Files From SAVRES V7.1 on, full filenames may be specified as input and output files to be saved and restored. On saving, that file will be transferred to the tape. On restoring, if the file to which you are restoring exists, that file will have its contents replaced by data from the tape. If the file does not exist it will be created, of sufficient size to store the data from the file on the tape. If there is not sufficient room, an error message will be typed. When a file has to be created in this way, SAVRES will type a message to the user telling him this is being done, and telling him the file size. SAVRES V7.3 Users' Guide Page 2-6 Using SAVRES 2.3.4 Multivolume Tape Sets If the device being saved is too large to fit on one tape, SAVRES will prompt for the next volume to be mounted as required. The user should be careful to label each volume uniquely (for example with with a backup set "name" and "sequence number") during a save operation. On restore operations SAVRES will also prompt for the next volume to be mounted as required. If a volume is mounted out of sequence or is not part of the same volume set the system will prompt for the correct volume. 2.4 Verification of Disc Images Verification of disc images stored on floppy discs is NOT supported. There are two ways of initiating a tape verification: AFTER A SAVE: After a save to tape operation SAVRES will ask if the user wishes to immediately verify the tape image. A "Y" response will cause a tape verification to be started and a "N" response will result in a normal exit. VERIFICATION ONLY: When a tape is specified in response to the "From?" prompt and a disc is specified to the "To?" prompt, SAVRES is able to verify or to restore. It first asks if verification is desired. If the user responds "Y" to the "Do you wish to VERIFY? [Y/N]" prompt the verification will proceed. If the user responds "N" SAVRES will ask whether a restore to disc operation is desired. When verifying disc images stored on magtape (MS:, MT:, MT4:) it may be advantageous to use the tape drive in the slow speed mode (MS: or MT:), due to the fact that the tape may not stream in the fast speed mode (MS:/F or MT4:). Using the tape in the slow speed mode may take LESS time to complete the operation than if the tape was used in the fast speed mode. AUTOMATICALLY AFTER A SAVE OR RESTORE: If the data fits within one tape, you may append "/V" (auto-verify) to either the "From?" or "To?" filenames. You will not be asked to load the tape (this is assumed), nor will you be asked if you wish to verify. After the save or restore operation the tape will be rewound (regardless of /N or /S switches) and the data verified. [If you specify this switch the questions concerning restoring or verifying are replaced by one question "Do you wish to RESTORE then VERIFY?", as this switch would be redundant in verification!] Any errors detected during the verification procedure will be reported on the console. Each error report will give the block and word SAVRES V7.3 Users' Guide Page 2-7 Using SAVRES (decimal) at which the error occurred and the two data words involved. At the end of the verification process a count of the number of verification errors is displayed. Only one report will be made within any one block of data, rather than displaying every conflicting word. [Should a disc error occur, the user will be asked if he wishes to ignore it. In SAVRES V6 this suppressed any report of errors within this block. This has been removed in V7, generally resulting in an error report for that block.] 2.5 Restoring Disc Images If the image is to be restored from tape then the user must specify the tape in response to the "From?" prompt and the disc in response to the "To?" prompt. With this combination there are two options: verification or restoration. SAVRES first asks "Do you wish to VERIFY? [Y/N]", to which, if the user requires restoration rather than verification he should answer "N". The next prompt is "Do you wish to RESTORE? [Y/N]", to which he should answer "Y". This will cause SAVRES to perform a restore from tape to disc. [See the note concerning the /V switch in a previous section.] [If the image is to be restored from floppy discs the the verify option is not available.] 2.6 Running SAVRES from Bootable Tapes When running from bootable tapes the disc handler must be loaded using the LOAD command in STARTS.COM (STARTX.COM). This will overcome a problem which causes RMON to lose track of the location of the system tape handler. Once the specified operation is complete it is necessary to reboot the system since RMON will almost certainly have lost track of the system tape handler by this stage! CHAPTER 3 Switches in SAVRES 3.1 Multiple Files & Rewind Control (/N, /E, & /S) While it has always been possible for SAVRES to save multiple files on tapes, it was slow and inconvenient, requiring a complete rewind and scan through the tape for each file written, restored or verified. This is incredibly slow on cartridge tapes! In V7.1 an attempt has been made to allow multiple files with a little less inconvenience. A full RT-11 file string with wildcards has NOT been implemented (sorry!). Normally SAVRES rewinds the tape at the start, performs its operation, then rewinds the tape at the end. It is now possible to control these rewinds by appending a switch to the tape file specification: /N - no rewinds at either start or end. The effect of this is that when it is necessary to read from the tape, the search for the tape file will commence at the present tape position. When it is necessary to write to a tape, the tape is wound to the logical end of tape without rewinding, and the tape file commenced at that point. [Beware of /N with cartridges which have been overwritten. The operation may appear to proceed correctly, but data thus saved may prove inaccessible.] /S - rewind at the start only. The tape is rewound before SAVRES performs any reading or writing from or to it. On reading, the search for the tape file commences at the start of the tape, and on writing the tape will then be wound to the logical end of tape before starting to write. The tape will not be rewound after the SAVRES operation. /E - rewind at the end only. On reading, the search for the desired tape file commences at the present position of the tape, and on writing, the tape is wound from its present position to the logical end of tape without rewinding it. SAVRES V7.3 Users' Guide Page 3-2 Switches in SAVRES 3.2 Rewinding Only (/R & /U) Two switches are for rewinding or unloading the tape without performing any data transfer upon it. SAVRES exits after performing either of these operations. /R - rewind the tape. /U - rewind and unload the tape. 3.3 Physical Device I/O (/P) The switch /P is for accessing a device using physical I/O spfuns, allowing access to a complete physical unit despite the RT-11 device size limit of 65535 blocks. [This is designed to replace the previous "DUA:" kludge.] It allows saving of discs up to about 524 megabytes, even if partitions of those discs (other than partition 0) are not set up as units available to RT/TSX with SET PARTITION commands. An example of the use of /P is in the previous chapter. 3.4 Fast Tape Streaming (/F) In versions of SAVRES prior to 7.3, to make the MS: magnetic tape stream in fast streaming mode, the user called it "MS1:". This kludge has been removed, and replaced by the "/F" (FAST stream) switch. This will work on any tape device whose handler recognizes the SPFUN request (-9) which the MS: handler uses to set fast streaming mode. 3.5 Discussion on Rewinds It should be noted that when the starting rewind is suppressed, the user is not given the option about overwriting the tape. When the ending rewind is suppressed, the user is not given the option of verifying the tape after writing. The technique for saving multiple files on a tape is as follows: 1) Initialize your tape - either the INIT command for normal tapes, or run SCINIT for SC: cartridge tapes. 2) Copy the files to the tape, running SAVRES once per file transferred. Append /N to the tape filename. 3) If you wish to verify, you will need a second pass through the tape. You may rewind in any of three ways: - (simplest) type /R to SAVRES - use /E instead of /N when saving the last file - use /S instead of /N when verifying the first file SAVRES V7.3 Users' Guide Page 3-3 Switches in SAVRES 4) Verify the files running SAVRES once per file verified. Append /N to the tape filename. 5) Rewind the tape at the end. Again, you may run SAVRES and type /R (or /U to unload), or use /E instead of /N when verifying the last file. 3.6 Example - Saving & Verifying 6 Files Saving and verifying a series of six files (DU:UCL.DSK, DU:TSX.DSK, DU1:RPL6P.DSK,DU:LETTER.DSK, DU:MONITR.DSK, DU1:MEDSYS.DSK) to a cartridge tape SC:. Note how the default filenames are useful: {Initialize the cartridge tape properly} .r scinit SC0:/Initialize; Are you sure? Y SC0: Initialized {Suppress all rewinds with the /N switch} .r savres From? SY:UCL.DSK To? SC:/N SAVE a Disc (SY:UCL.DSK) onto SC:UCL.DSK Are You SURE [Y/N]?Y Mount volume 1 in SC : and type the RETURN key to continue. 1000 Blocks Transferred to Tape *** Successful SAVRES Completion *** .r savres From? SY:TSX.DSK To? SC:/N SAVE a Disc (SY:TSX.DSK) onto SC:TSX.DSK Are You SURE [Y/N]?Y Mount volume 1 in SC : and type the RETURN key to continue. 5000 Blocks Transferred to Tape *** Successful SAVRES Completion *** .r savres From? DU1:RPL6P.DSK To? SC:/N SAVE a Disc (DU1:RPL6P.DSK) onto SC:RPL6P.DSK Are You SURE [Y/N]?Y Mount volume 1 in SC : and type the RETURN key to continue. 3000 Blocks Transferred to Tape *** Successful SAVRES Completion *** .r savres From? DU:LETTER.DSK To? SC:/N SAVE a Disc (DU:LETTER.DSK) onto SC:LETTER.DSK Are You SURE [Y/N]?Y Mount volume 1 in SC : and type the RETURN key to continue. SAVRES V7.3 Users' Guide Page 3-4 Switches in SAVRES 3500 Blocks Transferred to Tape *** Successful SAVRES Completion *** .r savres From? DU:MONITR.DSK To? SC:/N SAVE a Disc (DU:MONITR.DSK) onto SC:MONITR.DSK Are You SURE [Y/N]?Y Mount volume 1 in SC : and type the RETURN key to continue. 8000 Blocks Transferred to Tape *** Successful SAVRES Completion *** {On the last, allow a rewind at the end with /E} .r savres From? DU1:MEDSYS.DSK To? SC:/E SAVE a Disc (DU1:MEDSYS.DSK) onto SC:MEDSYS.DSK Are You SURE [Y/N]?Y Mount volume 1 in SC : and type the RETURN key to continue. 8000 Blocks Transferred to Tape Verify the disc image? [Y/N] N Unload the tape? [Y/N] N *** Successful SAVRES Completion *** {Note the block sizes count 16-block "blocks" plus 1 header} .dir sc:/full 14-Feb-87 < UNUSED > 0 UCL .DSK 64 14-Feb-87 TSX .DSK 314 14-Feb-87 RPL6P .DSK 189 14-Feb-87 LETTER.DSK 220 14-Feb-87 MONITR.DSK 501 14-Feb-87 MEDSYS.DSK 501 14-Feb-87 6 Files, 1789 Blocks {Now for the verification} {Rewind at the start with /S, as the directory left us at the end of the tape.} .r savres From? SC:/S To? DU:UCL.DSK VERIFY or RESTORE a Disc (DU:UCL.DSK) from SC:UCL.DSK Do you wish to VERIFY ONLY? [Y/N] Y Mount volume 1 in SC : and type the RETURN key to continue. No errors in 1000 blocks compared. *** Successful SAVRES Completion *** .r savres From? SC:/N To? DU:TSX.DSK VERIFY or RESTORE a Disc (DU:TSX.DSK) from SC:TSX.DSK Do you wish to VERIFY ONLY? [Y/N] Y Mount volume 1 in SC : and type the RETURN key to continue. No errors in 5000 blocks compared. SAVRES V7.3 Users' Guide Page 3-5 Switches in SAVRES *** Successful SAVRES Completion *** .r savres From? SC:/N To? DU1:RPL6P.DSK VERIFY or RESTORE a Disc (DU1:RPL6P.DSK) from SC:RPL6P.DSK Do you wish to VERIFY ONLY? [Y/N] Y Mount volume 1 in SC : and type the RETURN key to continue. No errors in 3000 blocks compared. *** Successful SAVRES Completion *** .r savres From? SC:/N To? DU:LETTER.DSK VERIFY or RESTORE a Disc (DU:LETTER.DSK) from SC:LETTER.DSK Do you wish to VERIFY ONLY? [Y/N] Y Mount volume 1 in SC : and type the RETURN key to continue. No errors in 3500 blocks compared. *** Successful SAVRES Completion *** .r savres From? SC:/N To? DU:MONITR.DSK VERIFY or RESTORE a Disc (DU:MONITR.DSK) from SC:MONITR.DSK Do you wish to VERIFY ONLY? [Y/N] Y Mount volume 1 in SC : and type the RETURN key to continue. No errors in 8000 blocks compared. *** Successful SAVRES Completion *** {Allow a rewind at the end with /E. Alternatively, just use /N and run SAVRES again and give it "SC:/R" at "From?"} .r savres From? SC:/E To? DU1:MEDSYS.DSK VERIFY or RESTORE a Disc (DU1:MEDSYS.DSK) from SC:MEDSYS.DSK Do you wish to VERIFY ONLY? [Y/N] Y Mount volume 1 in SC : and type the RETURN key to continue. No errors in 8000 blocks compared. *** Successful SAVRES Completion *** {Just to show off version & HELP texts} .r savres From? { only} SAVRES V7.3 (26-Feb-87) Disc Save and Restore Utility. Enter "?" if you want help at any time From? ? Type the name of the device or file to read data from. Valid ones are: SAVRES V7.3 Users' Guide Page 3-6 Switches in SAVRES DM0:-DM7:, DU0:-DU7: Discs of various flavours SC: Cartridge tape MS: Magnetic tape MT0: Another mag tape (slow) MT4: ibid, (fast) DY:, SF: Floppy discs A filename may be supplied to (or from) any device except floppy discs. If none is specified for either input or output, SAVRES.FIL will be used. For help concerning switches, type "/?". From? /? Switches for SAVRES are: /N allowing no rewinds, /S allowing rewinds only at the start, /E allowing rewinds only at the end; /V verify after save/restore without asking the user (only if one volume only used) /P use physical I/O spfuns to access whole physical disc /R rewind the tape with no transfer of data, and /U unload, ibid. /F set MS: magnetic tape to fast streaming mode. {Example of tape rewinding and doing nothing else} From? SC:/R {rewind the tape} 3.7 Details for Command Files If you have a series of files to be saved and verified, it may be easiest to set up a command file to do this. If you need to initialize a tape, include the line (example for MS:) -------------------- INIT MS:/NOQ -------------------- If you need to initialize a cartridge, include the lines -------------------- R SCINIT Y {in answer to ARE YOU SURE question} -------------------- For each file you wish to save, include the following -------------------- SAVRES V7.3 Users' Guide Page 3-7 Switches in SAVRES R SAVRES name of file to be saved, eg DU:TSX.DSK name of file on tape, with /N appended, eg SC:/N, SC:TSX.V6/N Y {in answer to ARE YOU SURE} blank line {answering MOUNT VOLUME 1} -------------------- Rewind the tape by including -------------------- R SAVRES SC:/R {or MS: or whatever device you are using} -------------------- For each file verified, include the following -------------------- R SAVRES name of file on tape, with /N appended, eg SC:/N, SC:TSX.V6/N name of file which was saved, eg DU:TSX.DSK Y {in answer to VERIFY?} Y {in answer to ARE YOU SURE?} blank line {in answer to MOUNT VOLUME 1} -------------------- Rewind the tape again by including -------------------- R SAVRES SC:/R {or MS: or whatever device you are using} -------------------- Here is the contents of an actual command file used by the author in testing this version of SAVRES. A couple of points: - The use of a file extension comprising the month as a hex digit followed by the last two digits of the year is helpful in remembering when the data was saved, as well as allowing multiple copies of the same data on one tape with no ambiguity. - The use of default filenames for the tape device when a named disc file is used. r savres du1:medsys.dsk sc:medsys.287/n y r savres du1:rpl6p.dsk sc:rpl6p.287/n y r savres SAVRES V7.3 Users' Guide Page 3-8 Switches in SAVRES du:monitr.dsk sc:rt11.v53/n y r savres du1:rt11.v54 sc:/n y r savres du1:cvllib.287 sc:/n y r savres du:tsx.dsk sc:tsx.6/n y r savres du1:ford.dsk sc:ford.87/n y r savres du1:savres.v71 sc:/n y r savres du:adrcvl.dsk sc:adrcvl.287/n y r savres du:lett85.dsk sc:lett85.287/n y r savres sc:/r r savres sc:medsys.287/n du1:medsys.dsk y r savres sc:rpl6p.287/n du1:rpl6p.dsk y r savres sc:rt11.v53/n du:monitr.dsk y SAVRES V7.3 Users' Guide Page 3-9 Switches in SAVRES r savres sc:/n du1:rt11.v54 y r savres sc:/n du1:cvllib.287 y r savres sc:tsx.6/n du:tsx.dsk y r savres sc:ford.87/n du1:ford.dsk y r savres sc:/n du1:savres.v71 y r savres sc:adrcvl.287/n du:adrcvl.dsk y r savres sc:lett85.287/n du:lett85.dsk y r savres sc:/r !End of command file. CHAPTER 4 Restrictions 4.1 Tape Streaming 4.1.1 Streaming under TSX-plus Version 7 of SAVRES has quite considerable enhancements to its ability to stream. Earlier versions will not stream with verification under TSX-plus. SAVRES will "hog" the system under TSX-plus, and other jobs running at the same time will cause loss of streaming, for save, restore and verify. It is strongly recommended that SAVRES backing up be performed when it is possible for it to be the only job running on the system. Caching under TSX-plus will cause loss of streaming. If possible, set TSX caching off during SAVRES operations. [The WA handler can be valuable here - see DUCM/DYC Websters/DECUS submission.] 4.1.2 Tape Streaming during Verification Tape streaming on disc image verification operations is not guaranteed. 4.1.3 Cartridge Tape (SC) Streaming If the disc (DU) is three way interleave format, then the cartridge will stream under all conditions. If the disc (DU) is two way interleave format then the following combination of components will guarantee streaming: a. bus arrangement of CPU, SRQD-11 (DU), PCLV-11 (MFU), then anything else (including magtape, floppy disc controller, etc) b. PCLV-11 (MFU) microcode version 6 or greater SAVRES V7.3 Users' Guide Page 4-2 Restrictions c. 11/23 or faster cpu 4.1.4 Magtape (MS:/F) Streaming If the disc (DU) is three way interleave format operations on the magtape may not stream. If the disc (DU) is two way interleave format, operations on the magtape will stream if the following conditions are met: a. bus arrangement of CPU, SRQD-11 (DU), PCLV-11 (MFU), then anything else (including magtape, floppy disc controller, etc) b. PCLV-11 (MFU) microcode version 6 or greater c. SRQD-11 (DU disc) with two way interleave format d. SAVREX is used under the XM environment 4.2 XM Monitor Restrictions Use of the MSCP disc (DU) requires the new version of DUX.SYS (release 05., version 10.), otherwise SAVRES (SAVREX) will fail. The Webster DUCM internally queueing DU handler should be marginally better in terms of streaming ability. The SC: and MS: handlers must be loaded manually under the XM monitor before use, since the XM monitor cannot successfully fetch these handlers for SAVRES. This is a restriction imposed by the XM monitor [prior to RT V5.4 anyway] and there does not appear to be an easy way around this problem. If these devices are specified and are not loaded, SAVRES will try to run but results are not guaranteed! 4.3 GPMI Restrictions Multivolume cartridge tape support is NOT available on GPMI machines. 4.4 General Restrictions Use of the cartridge tape will require the new version of SC.SYS or SCX.SYS if running under the XM environment (release 05., version 17.). SAVRES will fail if a previous version of the handler is used. It is recommended that either SC handler (SCOLD or SCNEW) distributed with V7.1 of SAVRES be used, as they contain several bug fixes and allow verification of multiple files without rewinding. [SCNEW is recommended]. SAVRES V7.3 Users' Guide Page 4-3 Restrictions SAVRES will require 22420 octal bytes of memory (just under 5k words) to begin with. Each buffer requires 20002 octal bytes above this requirement. SAVREX will require 22420 octal bytes of low memory. Each buffer requires 20002 octal bytes of extended memory. Handlers require varying amounts depending upon which handlers will be used. Verification requires room for at least three buffers. Under TSX-plus it is strongly recommended that there be allowed room for at least four buffers. When this is available, both the disc and the tape I/O will be at least double buffered for verification. This increases the possibility of streaming considerably. Due to an oddity in TSX-plus, and to limitations of the normal NL handler, using SAVRES with NL as the output device will not work. [There is a special NL handler for it for testing, hence the code in the sources.] CHAPTER 5 Update Comments 5.1 Improvements on SAVRES 4.2b 5.1.1 Virtual SAVRES Two versions of SAVRES are offered. The conventional SAVRES.SAV which will run under all RT-11 monitors (although under the XM environment only two buffers can be allocated) and SAVREX.SAV (a virtual version of SAVRES.SAV) which can only be run under the XM environment but is subject to some restrictions with respect to device handler loading. 5.1.2 DU Support Later versions of SAVRES allow the MSCP DU: disc to be saved onto or restored from tape or floppy in one pass. All blocks on the disc are accessed (including the invisible block between successive partitions) and SAVRES will perform the operation over several tapes if necessary. [In V7.1 the ability to perform physical I/O has been performed, hopefully to supercede this technique eventually. With it up to 524 megabytes may be saved from one unit.] To allow SAVRES to access the entire DU: disc the following SET options must be in effect (substitute DA for DU for second MSCP controller) : UNLOAD DU SET DU1 UNIT=0,PART=1 SET DU2 UNIT=0,PART=2 SET DU3 UNIT=0,PART=3 SET DU4 UNIT=0,PART=4 SET DU5 UNIT=0,PART=5 SET DU6 UNIT=0,PART=6 SET DU7 UNIT=0,PART=7 LOAD DU SAVRES V7.3 Users' Guide Page 5-2 Update Comments The command syntax has not improved. To specify that an operation be performed on the entire DU: disc, the user must specify DUA: as the disc to be used (as opposed to DU:, DU0:, DU1:, ..., DU7:). The suffix "A" indicates that "all" the disc should be considered in the following operation. E.g. Specifying DUA: will operate on the entire disc capacity (up to 256Mb). Specifying DU: or DU0: will only operate on up to the first 32Mb. 5.1.3 Multivolume Tape Support SAVRES will request another tape volume if the current tape does not have enough data or free space to complete the requested operation. Multivolume support is offered for both cartridge tapes (SC:) and magtapes (MS:). Multivolume tape support is NOT available on GPMI machines with cartridge tapes. 5.1.4 Tape Checks 5.1.4.1 Tape Integrity Check - If the user specifies that a tape be overwritten, sixteen special blocks of data will be written to the tape initially and subsequently read to verify the integrity of the media. This block of data is given the filename $$$$$$.$$$ and can be seen if a directory is obtained of the tape. The integrity check is NOT performed if the tape is NOT overwritten. During the tape integrity checking process SAVRES will display the message: ** Testing ** on the terminal. 5.1.4.2 Volume Number Check - Volume identification is written onto each tape during the save to tape operation. This identification is only read during restore to disc and tape verification operations. If the incorrect volume is supplied during a restore to disc or tape verification operation, the user will be told that the wrong volume has been mounted and will be prompted to mount the correct volume. SAVRES V7.3 Users' Guide Page 5-3 Update Comments 5.1.4.3 Volume Compatibility Check - SAVRES will check that volumes mounted subsequent to the first volume belong to the same set. A volume set is defined to be a collection of tapes which were mounted during one save to tape operation. If the user inadvertently mounts an incompatible volume a message will be printed indicating that the wrong volume has been mounted and will be prompted to mount the correct volume. 5.1.4.4 Disc Size Check - On a restore to disc operation SAVRES will check that the size of the disc being restored is the same as the size of the disc which was saved onto the tapes. If not, a warning message is displayed and the user is prompted to proceed or not. 5.1.5 Disc Image Verification Disc images saved on tape may be verified against the original disc to ensure the validity of the save to tape operation. Unfortunately, the additional overheads incurred during this process may result in the tape not streaming. The verification process is NOT supported for floppy discs. 5.1.6 SAVRES 4.2b Compatibility Mode SAVRES can RESTORE disc images created by SAVRES 4.2b, it cannot however SAVE discs in a SAVRES 4.2b image. Thus older tapes can still be restored without having to resort to an older version of SAVRES. SAVRES will prompt the user when it senses a SAVRES 4.2b tape. The user may then either go ahead and restore the old disc image or abort the process and mount a new tape. SAVRES may inadvertently think that the tape is a SAVRES 4.2b image if a tape error occurs, the user should therefore only proceed with the restoration of an old SAVRES 4.2b image if there is no doubt whatsoever that the image on the tape was in fact created using SAVRES 4.2b. In this mode of operation all the new SAVRES features are NOT enabled. Note that SAVRES 4.2b CANNOT successfully read disc images from tapes created using the new versions of SAVRES. Attempts to restore the new disc images from magtape using SAVRES 4.2b will fail. Attempts to restore the new disc image from cartridge tape using SAVRES 4.2b will appear to work but will in fact have CORRUPTED the disc. SAVRES V7.3 Users' Guide Page 5-4 Update Comments 5.1.7 Answers to Prompts Prompts which require a "Yes" or "No" answer must be given either a "Y" or "N" response. Any other response will cause the system to redisplay the prompt. 5.2 Changes from V6 to V7 The multiple-buffering code in SAVTAP has been completely rewritten, to allow streaming on verification under TSX-plus. As a side effect, the chances of streaming under verification under other situations should be markedly enhanced. This requires however room for at least four buffers. The SAVTAP module has been broken into three separate overlays (SAVSAV, SAVRST, and SAVVER) to reduce the size of the programme portion of SAVRES to just under 5k words. Assorted bugs (the ability of SAVRES to hang occasionally, the ability to cross groups of 16 disc blocks when using an internally-queueing disc handler, and a few minor funnies) have been removed, undoubtedly leaving other more perverse beasties to be unearthed in their wake. Some of the error messages have been tidied (or just slightly altered). For example, a comparison error is now typed in one line instead of two. Verification code has been streamlined (thanks to Chris Kleinschmidt). 5.3 Changes V7 to V7.2 The ability to directly deal with disc files without having to mount them as logical discs has been included, with some changes to the default filename pattern (see Filenames, Chapter 2). Switches have been added allowing control of rewinds (see Chapter 3). This makes it possible to save multiple files upon a tape within finite time rather than with infinite time! This showed up a bug in FSMSC, so you will need to upgrade your SC handler if you wish to take advantage of this on your SC. Previously a copy of CVLLIB was required to link SAVRES. CVLLIB routines required by SAVRES have been incorporated in the source code of SAVRES.MAC. The ability to save a physical disc via the SPFUNs in the DUCM handler has been implemented. This allows saving a physical unit of up to 524 SAVRES V7.3 Users' Guide Page 5-5 Update Comments megabytes on a series of tapes. Should a tape be incorrectly loaded, the initial SAVRES rewind (unless suppressed by the /N or /E switch) will detect an error. SAVRES will type a warning message to the user to check the tape loading, and give him an opportunity to try again. The reply to this prompt is read with TTYINs rather then GTLINs, so as to allow its use even when SAVRES is being run from a command file. In line with DEC patterns, the version number and startup message are not automatically typed on starting SAVRES. If you type a blank line at the first ("From?") prompt you will get this information. 5.4 Changes from V7.2 to V7.3 The kludge to allow fast streaming on MS: by calling it MS1: has been replaced by the /F switch. Some of the HELP messages have been tidied. As SAVRES no longer cares what type of discs are being used, references to "winchester" have been removed. The /V (auto-verify) switch has been added for files which fit on to one tape volume only. [Currently it would take quite a lot of work to extend it to multi-volume sets.] CHAPTER 6 Streaming Tape Information Here are pieces of information gleaned from various sources (especially Tom), which I wish I had known before I started hacking this bloody thing! The idea of a "STREAMING TAPE" is that once it has started it should never stop. A READ command starts the drive, and it will keep going until it hits an error or a file mark. The READ CONTINUATION command a la PCLV11 is a dummy read telling the PCLV11 that it is ready for more data rather than telling the cartridge unit anything. Similarly the WRITE, up to EOT or Write-File-Mark. Because of the restriction of no backspace command, there are significant modifications with respect to file marks and end of file and end of tape. The double file mark indicating end of tape is never written by the handler. One is written only, leaving blank tape (if the cartridge has been properly erased - which is what SCINIT is for) following. On a read, the blank tape is taken as another file mark by the handler. Should the user decide to backspace this command is ignored, and writing commences at the start of that blank tape, after the true file mark. User data is written by searching for the last single file mark followed by blank tape. You need blank tape following the last file mark in order for the handler to know where to write the next file. Note that because DUP's EOT comprises two tape marks (written as two separate WRITE TAPE MARK commands rather than a CLOSE to the handler), using DUP to initialize an SC tape results in a tape that you may write data to but never read. Therefore use "R SCINIT" rather than "INIT SC:" to _____ initialize tapes. Since this is the case, using the SAVRES "overwrite" option on cartridge tapes rules out the ability to store more than one backup on the tape. Overwriting results in a tape on which the remaining unused portion is undefined. There is a three-block buffer in the cartridge tape drive. On reading a series of blocks, the first and second will be read into the buffer, then once the third has commenced reading, the first will be sent to the controller. (Read on: there is sense in this!). On writing, there is a read-after-write check performed. Despite the minuscule size of the heads (glued on to their carrying arm!) the read-after-write head reads _____ not the block being written but the previous block. Should a RAW error be discovered, the block in error will be re-written, followed again by the block which follows it. Each block on each track of the tape has a block number (invisible to the user) attached to it. Thus on reading a SAVRES V7.3 Users' Guide Page 6-2 Streaming Tape Information tape which has suffered a RAW error, block n will be read, then block n+1, then block n again. Should the drive see this, it is sufficiently intelligent to realize that this situation occurs after a RAW error and will not give the controller the block in error. If the data is being sent too slowly to the cartridge, such that it misses a block on a write, it will re-write the last block (with the same ident number). Thus it is possible, by being just too slow providing data, to reduce the capacity of a 45meg cartridge to 22meg. If the drive gets a hard read error, the drive will stop the current operation and begin rewinding the tape. CHAPTER 7 Distribution and Assembly 7.1 Disribution SAVRES is distributed with the following files: SAVRES.RNO Documentation for SAVRES - Save & Restore Programme SAVRES.DOC SAVRES.SRC Compressed sources for SAVRES SAVRES.COM Command file to build SAVRES and SAVREX COMPRS.SAV Compress/decompress programme for sources SCNEW.MAC Mapped SC handler for TSX-plus. Works fine for RT but cannot be used to make SB (block structured handler). SCNEW.TSX Handler for TSX. SCNEW.SYS Handler for RT, assembled with no options. TSXPRE.MAC Prefix file for TSX assembly SETLIN.MAC Programme to set serial line parameters SETLIN.SAV SETLIN.DOC PCLV11.DOC Extract from the PCLV11-J Technical manual, describing this software distribution, CUTIL, SCINIT and bootable tape creation. SCOLD.COM Command file for generating the SC.SYS handler. SCOLD.MAC Source for RT-11 SC handler (provided to make SB handler) SCBLOK.COM Command file to generate SB block structured SC handler. SCBLOK.MAC Source for block-structured SC handler SB.SYS That handler CUTIL.MAC Cartridge Tape Maintenance Programme CUTIL.SAV REGDEF.MAC SC Register Definiions SCBOOT.SAV Programme to generate bootable SC tapes. SCINIT.MAC Programme to initialize SC tapes SCINIT.SAV SAVRES V7.3 Users' Guide Page 7-2 Distribution and Assembly SYSGEN.CND A SYSGEN conditional file - adapt for your own handler XM.MAC Prefix file to generate SAVREX DEBUG.MAC Prefix file to generate debug code within SAVRES 7.2 Assembly To generate SAVRES, copy SAVRES.SRC, SAVRES.COM, and COMPRS.SAV onto a working disc area. Then type .@SAVRES COMPRS will be run, expanding SAVRES.SRC into the source files. The three routines SAVRES (root segment), SAVINI (initialization) and SAVFLP (save on floppies) will be assembled. Then the three flavours of the tape routines will be assembled using prefix files with SAVTAP, providing SAVSAV (save onto tape), SAVRST (restore from tape), and SAVVER (verify). The routines will be linked as appropriate to their overlay positions, providing SAVRES.SAV, SAVRES.MAP and SAVREX.SAV and SAVREX.MAP 7.3 SCNEW - New SC Handler for RT and TSX-plus The SC handler, like all Magnetic Tape handlers, is huge. Under TSX-plus it is possible to "map" a handler into a region of high memory, thus removing it from the (rather tightly restricted) area of low memory. SCNEW is an SC handler designed to be installed within TSX-plus with the following definition: devdef maph,dma,hanbuf,reqalc Whilst it does not require allocation, things are a lot safer if this is used! SCNEW will work as a normal RT-11 (SJ, FB, XM) handler when assembled as per any ordinary handler. It does not require FSM or FSMSC as it has its own built in. [In fact it has some bug fixes over SCOLD SC SAVRES V7.3 Users' Guide Page 7-3 Distribution and Assembly handler.] To assemble it for TSX-plus use the following commands: .macro tsxpre+scnew/obj .link/nobit scnew/exe:scnew.tsx SCNEW provides a perfectly good SC handler for RT11 also, by assembling it with your own SYSGEN.CND. Its one known restriction is that it cannot be used to generate the SB block structured SC handler. APPENDIX I Index "A" suffix for Complete Disc . . . . . . . . . . . 2-4 /E - rewind at end only . . . . . . . . . . . . . 3-1 /N - no rewinds . . . . . . . . . . . . . . . . . 3-1 /P switch . . . . . . . . . . . . . . . . . . . . 3-2 /P switch - saving physical units . . . . . . . . 2-4 /R - rewind the tape . . . . . . . . . . . . . . . 3-2 /S - rewind at start only . . . . . . . . . . . . 3-1 /U - rewind and unload the tape . . . . . . . . . 3-2 /V switch - automatic verification . . . . . . . . 2-6 ? - Get Help Information . . . . . . . . . . . . . 2-1 Assigned Device Names . . . . . . . . . . . . . . 2-4 Automatic Verification (/V) . . . . . . . . . . . 2-6 Bootable Tape - Running SAVRES from . . . . . . . 2-7 Bugs (in V6) . . . . . . . . . . . . . . . . . . . 5-4 Caching (TSX) . . . . . . . . . . . . . . . . . . 4-1 Caching under TSX . . . . . . . . . . . . . . . . 2-5 Change to MS: streaming mode . . . . . . . . . . . 3-2 Check Disc Size . . . . . . . . . . . . . . . . . 5-3 Check for Loaded Tape . . . . . . . . . . . . . . 2-2, 5-5 Comparison of Disc & Tape Images . . . . . . . . . 2-6 Compatibility Mode (with V4.2b) . . . . . . . . . 5-3 Complete Disc - suffix "A" . . . . . . . . . . . . 2-4 Complete Disc Saving . . . . . . . . . . . . . . . 2-3 CVLLIB routines in SAVRES . . . . . . . . . . . . 5-4 Device Units - Saving . . . . . . . . . . . . . . 2-5 Disc (Complete) - suffix "A" . . . . . . . . . . . 2-4 Disc Images - Restoring . . . . . . . . . . . . . 2-7 Disc Size Check . . . . . . . . . . . . . . . . . 5-3 Discs - Large . . . . . . . . . . . . . . . . . . 2-6 DU "SET" Options . . . . . . . . . . . . . . . . . 2-4 DUCM handler - physical I/O . . . . . . . . . . . 2-4 Error Message Changes (V7) . . . . . . . . . . . . 5-4 Example - Serial Saving/Verifying . . . . . . . . 3-3 SAVRES V7.3 Users' Guide Page I-2 Fast speed tape mode (MS, MT) . . . . . . . . . . 2-6 Filenames - Defaults for Tape . . . . . . . . . . 2-2 Files - Saving . . . . . . . . . . . . . . . . . . 2-5 Floppy Verification . . . . . . . . . . . . . . . 2-6 GPMI Restrictions . . . . . . . . . . . . . . . . 4-2 Handler Loading . . . . . . . . . . . . . . . . . 4-2 Help Information - "?" . . . . . . . . . . . . . . 2-1 Ideas behind SAVRES . . . . . . . . . . . . . . . 1-1 Identification of Volumes . . . . . . . . . . . . 5-2 Information re Streaming Tape . . . . . . . . . . 6-1 Integrity Check on Tape . . . . . . . . . . . . . 5-2 Large Discs . . . . . . . . . . . . . . . . . . . 2-6 LD use for Saving Files . . . . . . . . . . . . . 2-5 Load Check for Tape . . . . . . . . . . . . . . . 2-2, 5-5 Loading Handlers . . . . . . . . . . . . . . . . . 4-2 Memory Requirements . . . . . . . . . . . . . . . 4-2 MS0:/MS1: streaming facility altered . . . . . . . 3-2 MS: fast streaming . . . . . . . . . . . . . . . . 5-5 Multiple Buffering . . . . . . . . . . . . . . . . 5-4 Multiple Files on one Tape . . . . . . . . . . . . 3-1 Multivolume Tape Sets . . . . . . . . . . . . . . 2-6 NL Restriction . . . . . . . . . . . . . . . . . . 4-3 NO answers . . . . . . . . . . . . . . . . . . . . 5-4 Overlays from SAVTAP . . . . . . . . . . . . . . . 5-4 Physical Device I/O - /P . . . . . . . . . . . . . 3-2 Physical Disc Saving . . . . . . . . . . . . . . . 2-3 Physical I/O . . . . . . . . . . . . . . . . . . . 5-4 Physical unit access - /P switch . . . . . . . . . 2-4 Prompts - Yes/No . . . . . . . . . . . . . . . . . 5-4 Re-booting System Disc . . . . . . . . . . . . . . 2-4 Restoring Disc Images . . . . . . . . . . . . . . 2-7 Restrictions . . . . . . . . . . . . . . . . . . . 4-1 Restrictions - GPMI . . . . . . . . . . . . . . . 4-2 Restrictions - under XM . . . . . . . . . . . . . 4-2 Rewinding Tape - Default/Control . . . . . . . . . 3-1 Running SAVRES . . . . . . . . . . . . . . . . . . 2-1 Saving Complete Discs . . . . . . . . . . . . . . 2-3 Saving Device Units . . . . . . . . . . . . . . . 2-5 Saving Files . . . . . . . . . . . . . . . . . . . 2-5 Saving up to 524 megabytes . . . . . . . . . . . . 2-4 SAVREX vs SAVRES . . . . . . . . . . . . . . . . . 5-1 SC Streaming . . . . . . . . . . . . . . . . . . . 4-1 Serial Saving/Verifying Example . . . . . . . . . 3-3 SET options for DU . . . . . . . . . . . . . . . . 2-4 Size of Disc - Check . . . . . . . . . . . . . . . 5-3 Slow speed tape mode (MS, MT) . . . . . . . . . . 2-6 SAVRES V7.3 Users' Guide Page I-3 Speeds of tapes (MS, MT) . . . . . . . . . . . . . 2-6 Startup Message . . . . . . . . . . . . . . . . . 5-5 Streaming - /F (high speed MS) . . . . . . . . . . 4-2 Streaming - SC . . . . . . . . . . . . . . . . . . 4-1 Streaming Mode - MS: tapes (altered) . . . . . . . 3-2 Streaming Restrictions . . . . . . . . . . . . . . 4-1 Streaming Tape - Technical information . . . . . . 6-1 Suffix "A" for Complete Disc . . . . . . . . . . . 2-4 Switches . . . . . . . . . . . . . . . . . . . . . 3-1 Switches (controlling rewinding) . . . . . . . . . 3-1 System Disc Re-booting . . . . . . . . . . . . . . 2-4 Tape Default Filenames . . . . . . . . . . . . . . 2-2 Tape Integrity Check . . . . . . . . . . . . . . . 5-2 Tape Load Check . . . . . . . . . . . . . . . . . 2-2, 5-5 Tape Rewinding - Default/Control . . . . . . . . . 3-1 Tape Sets - Multivolume . . . . . . . . . . . . . 2-6 Tapes containing Multiple Files . . . . . . . . . 3-1 Technical Information - Streaming Tape . . . . . . 6-1 TSX - Caching reduces speed . . . . . . . . . . . 2-5 TSX - Memory Recommendations . . . . . . . . . . . 4-3 TSX Caching . . . . . . . . . . . . . . . . . . . 4-1 TSX Streaming and Restrictions . . . . . . . . . . 4-1 Update - V6 to V7 . . . . . . . . . . . . . . . . 5-4 Update - V7 to V7.2 . . . . . . . . . . . . . . . 5-4 Update - V7.2 to V7.3 . . . . . . . . . . . . . . 5-5 Updates since V4.2b . . . . . . . . . . . . . . . 5-1 Verification - Automatic (/V) . . . . . . . . . . 2-6 Verification - Memory Requirements . . . . . . . . 4-3 Verification of Disc & Tape Images . . . . . . . . 2-6 Verification of Floppies . . . . . . . . . . . . . 2-6 Virtual SAVRES . . . . . . . . . . . . . . . . . . 5-1 Volume Identification . . . . . . . . . . . . . . 5-2 XM Restrictions . . . . . . . . . . . . . . . . . 4-2 YES answers . . . . . . . . . . . . . . . . . . . 5-4