HP OpenVMS Systems Documentation

$ ALLOCATE MUA0:,MUA1:,MUA2:(1)
%DCL-I-ALLOC, MUA0: allocated
%DCL-I-ALLOC, MUA1: allocated
%DCL-I-ALLOC, MUA2: allocated
$ BACKUP/IMAGE/RECORD/NOASSIST/RELEASE_TAPE
_From: DKA100:
_To: MUA0:FULL02.SAV,MUA1,MUA2/LABEL=MNTH(2)
%MOUNT-I-MOUNTED, MNTH mounted on _MUA0:
%BACKUP-I-RESUME, resuming operation on volume 2
%MOUNT-I-MOUNTED, MNTH02 mounted on _MUA1:
%BACKUP-I-RESUME, resuming operation on volume 3
%MOUNT-I-MOUNTED, MNTH03 mounted on _MUA2:
$

1. Allocate the tape drives that will be used in the backup.
2. Back up DKA100: to a save set. The /IMAGE qualifier indicates this operation is an image backup. BACKUP begins writing data to a save set on the tape in MUA0. If the tape in MUA0: becomes full, BACKUP initializes the tape in MUA1: and continues writing the save set. The tape in MUA1: gets the label MNTH02. If necessary, BACKUP also uses the tape in MUA2.
   The /RELEASE_TAPE qualifier dismounts and unloads an output tape device after BACKUP writes the save set. The /RECORD qualifier records the current date and time in the file header record of each file that is backed up.

As described in Section 11.2, an image backup of a disk provides you with an exact logical copy of all the files on the disk. You should perform image backups with no interactive users on the system because of open file considerations (described in Section 11.15.1). Also, system performance can be affected during the backup process, so it is best to schedule the backup during the least busy times for your system. You can optimize the speed of the backup procedure by ensuring that certain process and system parameters are set properly (as described in Section 11.7).

How to Perform This Task

To perform an image backup to a disk, use the BACKUP command in the following format:

The /IMAGE qualifier identifies the backup operation as an image backup. The /RECORD qualifier records the current date and time in the file header record of each file that is backed up. This information is essential for future incremental backups. The /SAVE_SET qualifier indicates that you are creating a save set on a disk.

Examples

1. For example, if you want to create an image backup save set of the disk named DUA1: on a disk named DUA2:, you could enter the following commands:

   $ MOUNT DUA1: USER1 %MOUNT-I-MOUNTED, USER1 mounted on _DUA1: $ MOUNT DUA2: USER2 %MOUNT-I-MOUNTED, USER2 mounted on _DUA2: $ BACKUP/IMAGE/RECORD _From: DUA1: _To: DUA2:[USER.BACKUPS]USER1.SAV/SAVE_SET

2. You can also specify multiple disk drives as the output specifier in the BACKUP command line. For example:

   $ BACKUP/IMAGE/RECORD _From: DUA0: _To: DUB24:[USER.BACKUPS]USER1.SAV,DUB25/SAVE_SET

As described in Section 11.2, an incremental backup of a disk provides you with an exact copy of only those files that have been created or modified since the last image or incremental backup in which the /RECORD qualifier was used.

How to Perform This Task

To perform an incremental backup to tape, perform the following steps:

1. Perform an image backup using the /RECORD qualifier (see Section 11.15.2).
2. To determine the date of the last backup that used the /RECORD qualifier, enter the DIRECTORY/FULL command and the file name. For example:

   $ DIRECTORY/FULL LOGIN.COM Directory WORK204:[HIGGINS] LOGIN.COM;31 File ID: (23788,1,0) Size: 7/9 Owner: [ACC,HIGGINS] Created: 30-APR-2000 14:37:33.98 Revised: 30-APR-2000 14:37:34.44 (1) Expires: <None specified> Backup: 30-APR-2000 20:20:57.37 File organization: Sequential File attributes: Allocation: 9, Extend: 0, Global buffer count: 0, No version limit Record format: Variable length, maximum 94 bytes Record attributes: Carriage return carriage control RMS attributes: None Journaling enabled: None File protection: System:RWED, Owner:RWED, Group:RE, World: Access Cntrl List: None Total of 1 file, 7/9 blocks.

   
   The date of the last /RECORD backup is indicated in the Backup field of the display. In this example, a /RECORD backup was performed on 30-APR-2000 20:20:57.37.

   Note If you used the /IGNORE=INTERLOCK qualifier to back up open files during your last image backup or incremental backup in which the /RECORD qualifier was used, see Section 11.18.3. If the files remain open, they will not be included in the incremental backup because their backup date fields are not as recent as the last image backup or incremental backup in which the /RECORD qualifier was used.

3. Enter the BACKUP command in the following format:

   BACKUP/RECORD/SINCE=BACKUP input-specifier output-specifier[/LABEL=label] [/REWIND]

   
   The /RECORD qualifier records the current date and time in the file header record of each file that is backed up. This information is essential for future incremental backups. The /SINCE=BACKUP qualifier backs up files dated later than the last /RECORD backup. The /REWIND qualifier is optional depending on whether you want to initialize the tape. The /LABEL qualifier identifies the label of the tape.

Example

The following command is an example of an incremental backup in which BACKUP saves all files on DRA1: that were modified since the previous BACKUP/RECORD command and stores them in a save set named 20APR2000.SAV:

$ BACKUP/RECORD/SINCE=BACKUP/RELEASE_TAPE
From: DRA1:[000000...]
To: MIA0:20APR2000.SAV/LABEL=20JUNE

The /LABEL qualifier identifies the volume label of the tape. Also, because BACKUP is performing an incremental rather than an image backup, it is necessary to explicitly use the notation DRA1:[000000...] to specify all the files on DRA1. The /SINCE=BACKUP qualifier saves all files created or modified since the last /RECORD backup. The /RELEASE_TAPE qualifier dismounts and unloads an output tape device after BACKUP writes the save set and before it performs the action of the /RECORD command.

11.15.5 Performing Incremental Backups to Disk

As described in Section 11.2, an incremental backup of a disk provides you with an exact copy of only those files that have been created or modified since the last image or incremental backup in which the /RECORD qualifier was used.

How to Perform This Task

To make an incremental backup to disk, perform the following steps:

1. To perform an incremental backup, you must first perform an image backup using the /RECORD qualifier (see Section 11.15.2).
2. To determine the date of the last backup that used the /RECORD qualifier, enter the DIRECTORY/FULL command and the file name. For example:

   $ DIRECTORY/FULL LOGIN.COM Directory WORK204:[HIGGINS] LOGIN.COM;31 File ID: (23788,1,0) Size: 7/9 Owner: [ACC,HIGGINS] Created: 30-APR-2000 14:37:33.98 Revised: 30-APR-2000 14:37:34.44 (1) Expires: <None specified> Backup: 30-APR-2000 20:20:57.37 File organization: Sequential File attributes: Allocation: 9, Extend: 0, Global buffer count: 0, No version limit Record format: Variable length, maximum 94 bytes Record attributes: Carriage return carriage control RMS attributes: None Journaling enabled: None File protection: System:RWED, Owner:RWED, Group:RE, World: Access Cntrl List: None Total of 1 file, 7/9 blocks. $

   
   The date of the last /RECORD backup is indicated in the Backup field of the display. In this example, a /RECORD backup was performed on 30-APR-2000 20:20:57.37.

   Note If you used the /IGNORE=INTERLOCK qualifier to back up open files during your last image backup or incremental backup in which the /RECORD qualifier was used, see Section 11.18.3. If the files remain open, they will not be included in the incremental backup because their backup date fields are not as recent as the last image backup or incremental backup in which the /RECORD qualifier was used.

3. Enter the BACKUP command in the following format:

   BACKUP/RECORD/SINCE=BACKUP input-specifier output-specifier/SAVE_SET

   
   The /RECORD qualifier records the current date and time in the file header record of each file that is backed up. The first step in an incremental backup is an image backup (see Section 11.15.2). If you plan to perform incremental backups, you must use the /RECORD qualifier when you perform image backups. The /SINCE=BACKUP qualifier backs up files dated later than the last /RECORD backup. The /SAVE_SET qualifier indicates that you are creating a save set on a disk.

Examples

1. To create an incremental backup of a disk named DUA55: on a sequential disk save set on a disk named DJC12:, you could enter the following commands:

   $ MOUNT DUA55: DISK1 %MOUNT-I-MOUNTED, DISK1 mounted on _DUA55: $ MOUNT/FOREIGN DJC12: %MOUNT-I-MOUNTED, DISK2 mounted on _DJC12: $ BACKUP/RECORD/SINCE=BACKUP _From: DUA55:[000000...] _To: DJC12:USER1.SAV/SAVE_SET

2. You can also specify multiple disk drives as the output device in the BACKUP command line. For example:

   $ MOUNT DUA0: USER1 %MOUNT-I-MOUNTED, USER1 mounted on _DUA0: $ MOUNT/FOREIGN DUB24: %MOUNT-I-MOUNTED, DISK2 mounted on _DUB24: $ MOUNT/FOREIGN DUB25: %MOUNT-I-MOUNTED, DISK3 mounted on _DUB25: $ BACKUP/RECORD/SINCE=BACKUP _From: DUA0:[000000...] _To: DUB24:USER1.SAV,DUB25/SAVE_SET

An incompatibility between the operating procedures of the PATHWORKS for OpenVMS Macintosh server and OpenVMS incremental backup operations can cause BACKUP to save entire disks or directory structures, including subdirectories and files.

BACKUP can detect whether a directory file has been modified since the date indicated by the Backup Date field in the file header. If a directory file has been modified, all subdirectories and files of that directory are saved for possible later restore operations.

Updating the modification date of directory files is unusual for OpenVMS systems. However, it can happen if, for example, you rename a directory file from one location to another. In contrast, the PATHWORKS Macintosh server maintains the modification date of directory files for Macintosh users; that is, it updates the modification date for each directory change, file creation, and file deletion.

Thus, an incremental backup of a disk where PATHWORKS is used to serve files to Macintosh users may result in saving the entire disk or entire directories (including their subdirectories and files) instead of just the user files that were created or modified since the last incremental backup operation.

You can avoid saving files unnecessarily in either of the following ways:

• By using the /NOINCREMENTAL qualifier.
  On a save operation, you can use the BACKUP qualifier /NOINCREMENTAL to avoid saving all the files and subdirectories under directories that have been modified. (Some files will, however, still be saved.) Use this qualifier only if you are sure that you do not want to save all data.
  Prior to OpenVMS Version 6.2, the system, by default, did not save the files and subdirectories that were under directories that had been modified. In OpenVMS Versions 7.0 and 7.1, to ensure a successful restore, the system saved all files and subdirectories under directories that had been modified. This behavior, however, sometimes resulted in saving files and subdirectories that were not needed for later restore operations. The /NOINCREMENTAL qualifier allows you more control over the amount of file data that is saved.
• By performing a "dummy" BACKUP/RECORD operation on all directory files immediately before performing the incremental backup. For example:

  $ BACKUP/RECORD/IGNORE=(INTERLOCK) - _$ disk:[000000...]*.DIR;* - _$ NLA0:DUMMY.BCK/SAVE/NOCRC/GROUP_SIZE=0 $ $ BACKUP/VERIFY/FAST/RECORD/IGNORE=(INTERLOCK) - _$ /NOASSIST/COMMENT="Incremental backup of DISK:" - _$ disk:[000000...]*.*;*/SINCE=BACKUP - _$ tape:incr.bck/LABEL=incr/SAVE

  
  In this example, the first BACKUP command performs the dummy backup operation, and the second command performs the actual incremental backup. The first command updates the Backup Date field for all the directory files. Specifying the null output device NLA0:[000000...] causes a save set file not to be written. Because no file information needs to be retained from this operation, the /NOCRC and /GROUP_SIZE=0 qualifiers are specified to avoid CRC and XOR block calculation.

On a standalone workstation, you are probably responsible for backing up files on your user disks. Section 11.15.7.1, Section 11.15.7.2, and Section 11.15.7.3 contain command procedures for making image, incremental, and interactive backups of user disks on your workstation.

Compaq also provides two template command procedures in the SYS$EXAMPLES directory for you to use in designing BACKUP command procedures. These command procedures are called BACKUSER.COM and RESTUSER.COM.

If you are not familiar with using command procedures, refer to the OpenVMS User's Manual.

11.15.7.1 Using a Command Procedure for Nightly Image Backups

The following command procedure performs nightly image backups, backing up all the files on disk DUA2: to a tape in MUA0. The files are copied to a magnetic tape save set named FULL_BACKUP.SAV. This procedure is particularly useful for backing up files on a MicroVAX system or workstation.

How to Perform This Task

To use the command procedure, perform the following steps:

1. Ensure that you have a batch queue available on your system. (See Section 14.3 for information about setting up a batch queues.) You submit the command procedure only once, and it will execute daily at 2:00 A.M. The command procedure automatically resubmits itself at 2:00 each morning; however, you must physically load a tape each day or the backup procedure will fail. Even if the backup procedure fails, however, the command procedure will continue to resubmit itself.
2. From the SYS$MANAGER directory, create the command procedure as shown and call it SYSTEM_BACKUP.COM.

   $! $! Resubmit this procedure -- $ SUBMIT/AFTER="TOMORROW+2:0" SYS$MANAGER:SYSTEM_BACKUP $! $ ON ERROR THEN GOTO FAILURE $ SET PROCESS/PRIVILEGES=ALL $! $ REPLY/ALL - "Full Backup About to Begin. Open Files Will Not Be Saved" $! $ BACKUP /IMAGE DUA2: MUA0:FULL_BACKUP.SAV /REWIND /IGNORE=LABEL_PROCESSING $ DISMOUNT MUA0: $ EXIT $! $FAILURE: $ WRITE SYS$OUTPUT "---> Backup failed" $ WRITE SYS$OUTPUT "" $ DISMOUNT MUA0: $ EXIT

3. Edit the command procedure to reflect:
   • The name of the disk that you want to back up. To back up more than one disk, list each of the devices in the BACKUP command line. For example, you could substitute the following lines for the BACKUP command line in the preceding example:

     . . . $! $ BACKUP/IMAGE WORK_DISK MIA0:WORK_BACK.SAV/REWIND $ BACKUP/IMAGE PAYROLL_DISK MIA0:PAYROLL_BACK.SAV $! . . .

     
     If you plan to perform any incremental backups later, include the /RECORD qualifier in the BACKUP command line.
   • The name of the tape drive that you will use.
   • The name that you want to assign to the save set.
4. Write down the name of the save set that you assigned.
5. Submit the command procedure using the following command line (if you gave your procedure a file name other than SYS$MANAGER:SYSTEM_BACKUP.COM, substitute the appropriate file name):

   SUBMIT/NOPRINT/AFTER="TOMORROW+2:0"/QUEUE=queue_name SYS$MANAGER:SYSTEM_BACKUP

6. Be sure to change the tape daily and make sure that a tape is physically loaded on the device that you specified. When the backup is complete, keep the backup tape in a safe place and do not use the tape again until after you make another image backup of your disks.

To stop the procedure after you have submitted it, use the DELETE/ENTRY command. To find the entry number, use the SHOW ENTRY command. For example:

$ SHOW ENTRY
  Entry  Jobname         Username     Blocks  Status
  -----  -------         --------     ------  ------
     14  SYS_BACKUP   TPROULX                 Holding until 19-APR-2000 02:00
         On generic batch queue CLUSTER_BATCH
$ DELETE/entry=583

You can use a similar command procedure to perform nightly incremental backups of your disks. It might be more convenient to perform nightly incremental backups and weekly image backups if either of the following conditions applies:

• Interactive users are on your system at all times, and system performance is noticeably affected by backups.
• A full backup does not fit on a single magnetic tape, but an incremental backup does. In this case, an image backup requires the presence of an operator (to change the tape), whereas an incremental backup can be run as a batch job.

Suppose that you want to do nightly incremental backups at 11:00 P.M., except on Friday night, when you want to do an image backup. The following command procedure executes an incremental backup on three disks and automatically resubmits itself to run again the following night, except for Friday night.

How to Perform This Task

To use the procedure, follow these steps:

1. From the SYS$MANAGER directory, create the command procedure as shown and call it INCREMENTAL_BACKUP.COM.

   $! $! Resubmit this procedure -- $ SUBMIT/AFTER="TOMORROW+23:0" SYS$MANAGER:INCREMENTAL_BACKUP $! $ TODAY = f$cvtime("today",,"weekday") $ IF TODAY .EQS. "Friday" THEN GOTO DONE $! $ ON ERROR THEN GOTO FAILURE $ SET PROC/PRIV=(OPER,BYPASS) $! $ REPLY/ALL - "Incremental Backup About to Begin. Open Files Will Not Be Saved" $! $ BACKUP/RECORD/SINCE=BACKUP DRA0:[000000...] - MIA0:INCREMENT1.SAV /LABEL=INC1 $ BACKUP/RECORD/SINCE=BACKUP DRA1:[000000...] - MIA1:INCREMENT2.SAV /LABEL=INC2 $ BACKUP/RECORD/SINCE=BACKUP DRA2:[000000...] - MIA2:INCREMENT3.SAV /LABEL=INC3 $ DISMOUNT MIA0: $ DISMOUNT MIA1: $ DISMOUNT MIA2: $ EXIT $! $FAILURE: $ WRITE SYS$OUTPUT "---> Backup failed" $ WRITE SYS$OUTPUT "" $ DISMOUNT MIA0: $ DISMOUNT MIA1: $ DISMOUNT MIA2: $ EXIT

2. Edit the procedure to reflect:
   • The names of the disks that you want to back up
   • The name of the tape drive that you will use
   • The volume label of the tape
   • The name that you want to assign to the save set
   • The day of the week (if any) to be omitted in the incremental backup
   
   In this example, the incremental backup will not be performed on Friday, reserving that day for an image (full) backup.
3. Be sure that an image backup has been made and also be sure that you continue to make regular image backups. When you make your image backups, be sure to use the /RECORD qualifier (as well as the /IMAGE qualifier) in your BACKUP command line.
4. Submit the command procedure using the following command line (if you gave your procedure a file name other than SYS$MANAGER:INCREMENTAL_BACKUP.COM, substitute the appropriate file name):

   $ SUBMIT/AFTER=23 SYS$MANAGER:INCREMENTAL_BACKUP

5. Be sure that a tape is physically loaded on the device that you specified. When the incremental backup is complete, keep the tape in a safe place and do not use the tape again until you make another image backup.