May 18, 1985 INCBUP - RT-11 Incremental Backup R. W. Barnard Sandia National Laboratories Minicomputer Software Division 7523 P. O. Box 5800 Albuquerque, NM 87185 (505) 844-5115 Introduction ____________ INCBUP is an IND control file which provides RT-11 users an incremental backup facility quite similar to RSX BRU or VMS BACKUP. Using INCBUP, backups can easily be done on files created since a specified date. The backup volume can be either a physi- cal disk or a logical disk residing on a larger device. In the case of the latter, the subdevice files are given unique names, so backups from the same source volume made on different dates can be stored on the same backup device. INCBUP uses the DECUS Library program DSKLIB, #11-743, (also available on the Spring and Fall, 1984, RT SIG tapes) to catalog the backed-up files for instantane- ous reference. (Try it - you will see that DSKLIB works essentially instantaneously)! INCBUP supports RT-11 multivolume copies, and has considerable error checking. Some definitions: Source Volume is the disk or subdevice file ______ ______ to be backed up. Backup Volume is the disk or subdevice file that ______ ______ you are copying the files to. If the backup volume is a logical device, the physical disk that it resides on is the Backup Device. ______ ______ Setup _____ You can change the names of certain defaults in INCBUP. To do so, edit the file and search for the string "Change". Immedi- ately following each instance will be some device specification or string that you can change. INCBUP expects that you will have already created a DSKLIB catalog called INCBUP.DLB on SY:. This is a secondary catalog, not your primary DSKLIB catalog. (Refer to the DSKLIB documentation for more details). Useage ______ You run INCBUP by typing R IND *SY:INCBUP or IND SY:INCBUP INCBUP - RT-11 Incremental Backup Page 2 The parameters of INCBUP, which may be included after the file name in the first case, are: Source_Volume Backup_Volume Date Backup_Device If any of these are not provided, the file will prompt for them. The files you have backed up can be located with the DSKLIB F(ind) command. Mechanics _________ INCBUP creates backup volumes which are initialized according to the DSKLIB protocol. The volume ID is of the form nnnBakDEVMDA, where nnn is a 3-digit serial disk number (zero filled), BakDEV is the volume name (the source volume device name will be substituted for DEV), and MDA is the date of the backup (April 13 is 413, October 9 is O09). The disk number is automati- cally read from a file SY:INCBUP.DAT, and the correctly updated number will be written to INCBUP.DAT when INCBUP finishes. INCBUP uses logical device LD4 as the default when a subdev- ice is specified for the backup volume. The subdevice file must be able to fit on your backup device, or INCBUP will prompt you to put in a new disk. If the number of blocks you need to back up is greater than the size of your backup device, you can use the RT-11 COPY/MULTIVOLUME facility. To do this, specify the backup volume to be a physical disk. INCBUP will then automatically copy your files in /MULTIVOLUME mode. Note that you must initialize each backup device disk that you expect to use before you start, because COPY/MULTIVOLUME doesn't let you stop in the middle to do initializations. It isn't necessary to do the correct volume identification when you initialize, because INCBUP will reinitial- ize the volume ID of each backup device disk that you have used. The output from INCBUP is a printer directory listing of the files you have backed up. Additionally, the files are catalogued in the DSKLIB catalog with a unique DSKLIB disk serial number. DSKLIB is run by the program DLBCOM, which provides for chain entry into DSKLIB, and a command line of DSKLIB commands. The format of the command line should not be changed unless you are familiar with DSKLIB. Restriction ___________ If you assign the logical name WF (Work File) to a device you are backing up, INCBUP will not copy the correct files. The file WF:DSKLIB.COM may be copied in place of one which was originally specified. If WF is assigned to the VM memory device, this won't happen.