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restor(8) [bsd man page]

RESTOR(8)						      System Manager's Manual							 RESTOR(8)

NAME
restor - incremental file system restore SYNOPSIS
restor key [ argument ... ] DESCRIPTION
Restor is used to read magtapes dumped with the dump command. The key specifies what is to be done. Key is one of the characters rRxt optionally combined with f. f Use the first argument as the name of the tape instead of the default. r or R The tape is read and loaded into the file system specified in argument. This should not be done lightly (see below). If the key is R restor asks which tape of a multi volume set to start on. This allows restor to be interrupted and then restarted (an icheck -s must be done before restarting ). x Each file on the tape named by an argument is extracted. The file name has all `mount' prefixes removed; for example, /usr/bin/lpr is named /bin/lpr on the tape. The file extracted is placed in a file with a numeric name supplied by restor (actually the inode number). In order to keep the amount of tape read to a minimum, the following procedure is recommended: Mount volume 1 of the set of dump tapes. Type the restor command. Restor will announce whether or not it found the files, give the number it will name the file, and rewind the tape. It then asks you to `mount the desired tape volume'. Type the number of the volume you choose. On a multivolume dump the recom- mended procedure is to mount the last through the first volume in that order. Restor checks to see if any of the files requested are on the mounted tape (or a later tape, thus the reverse order) and doesn't read through the tape if no files are. If you are working with a single volume dump or the number of files being restored is large, respond to the query with `1' and restor will read the tapes in sequential order. If you have a hierarchy to restore you can use dumpdir(8) to produce the list of names and a shell script to move the resulting files to their homes. t Print the date the tape was written and the date the file system was dumped from. The r option should only be used to restore a complete dump tape onto a clear file system or to restore an incremental dump tape onto this. Thus mkfs /dev/hp0a 4807 restor r /dev/hp0a is a typical sequence to restore a complete dump. Another restor can be done to get an incremental dump in on top of this. A dump followed by a mkfs and a restor is used to change the size of a file system. FILES
/dev/rmt1 default file name rst* temporary files SEE ALSO
dump(8), dumpdir(8), mkfs(8) DIAGNOSTICS
There are various diagnostics involved with reading the tape and writing the disk. There are also diagnostics if the i-list or the free list of the file system is not large enough to hold the dump. If the dump extends over more than one tape, it may ask you to change tapes. Reply with a newline when the next tape has been mounted. Dump tapes made before the new ondisc directory structure will be converted automatically by restor . BUGS
There is redundant information on the tape that could be used in case of tape reading problems. Unfortunately, restor does't use it. 3rd Berkeley Distribution RESTOR(8)

Check Out this Related Man Page

DUMP(8) 						      System Manager's Manual							   DUMP(8)

NAME
dump - incremental file system dump SYNOPSIS
dump [0123456789BchfusTdWwn [argument ...]] [filesystem] DESCRIPTION
Dump copies to magnetic tape all files changed after a certain date in the filesystem. The following options are supported by dump: 0-9 This number is the `dump level'. All files modified since the last date stored in the file /etc/dumpdates for the same filesystem at lesser levels will be dumped. If no date is determined by the level, the beginning of time is assumed; thus the option 0 causes the entire filesystem to be dumped. B records The number of dump records per volume. This option overrides the calculation of tape size based on length and density. c This option requires no further options. Used to specify that the tape is a cartridge drive rather than a 9-track. h level Honor the user 'nodump' flags only for dumps at or above the given level. The default honor level is 1, so that incremental backups omit such files but full backups retain them. f Place the dump on the next argument file instead of the tape. If '-' is given then standard out (stdout) is written to. u If the dump completes successfully, write the date of the beginning of the dump on file /etc/dumpdates. This file records a separate date for each filesystem and each dump level. The format of /etc/dumpdates is readable by people, consisting of one free format record per line: filesystem name, increment level and ctime(3) format dump date. /etc/dumpdates may be edited to change any of the fields, if necessary. Note that /etc/dumpdates is in a format different from that which previous versions of dump maintained in /etc/ddate, although the information content is identical. s The size of the dump tape is specified in feet. The number of feet is taken from the next argument. When the specified size is reached, dump will wait for reels to be changed. The default tape size is 2300 feet. d The density of the tape, expressed in BPI, is taken from the next argument. This is used in calculating the amount of tape used per reel. The default is 1600. T date Use the specified date as the starting time for the dump instead of the time determined from looking in /etc/dumpdates. The format of date is the same as that of ctime(3). This option is useful for automated dump scripts that wish to dump over a specific period of time. The T option is mutually exclusive with the u option. W Dump tells the operator what file systems need to be dumped. This information is gleaned from the files /etc/dumpdates and /etc/fstab. The W option causes dump to print out, for each file system in /etc/dumpdates the most recent dump date and level, and highlights those file systems that should be dumped. If the W option is set, all other options are ignored, and dump exits immedi- ately. w Is like W, but prints only those filesystems which need to be dumped. n Whenever dump requires operator attention, notify by means similar to a wall(1) all of the operators in the group "operator". If no arguments are given, the key is assumed to be 9u and a default file system is dumped to the default tape. Dump requires operator intervention on these conditions: end of tape, end of dump, tape write error, tape open error or disk read error (if there are more than a threshold of 32). In addition to alerting all operators implied by the n key, dump interacts with the operator on dump's control terminal at times when dump can no longer proceed, or if something is grossly wrong. All questions dump poses must be answered by typing "yes" or "no", appropriately. Since making a dump involves a lot of time and effort for full dumps, dump checkpoints itself at the start of each tape volume. If writing that volume fails for some reason, dump will, with operator permission, restart itself from the checkpoint after the old tape has been rewound and removed, and a new tape has been mounted. Dump tells the operator what is going on at periodic intervals, including usually low estimates of the number of blocks to write, the num- ber of tapes it will take, the time to completion, and the time to the tape change. The output is verbose, so that others know that the terminal controlling dump is busy, and will be for some time. Now a short suggestion on how to perform dumps. Start with a full level 0 dump dump 0un Next, dumps of active file systems are taken on a daily basis, using a modified Tower of Hanoi algorithm, with this sequence of dump lev- els: 3 2 5 4 7 6 9 8 9 9 ... For the daily dumps, a set of 10 tapes per dumped file system is used on a cyclical basis. Each week, a level 1 dump is taken, and the daily Hanoi sequence repeats with 3. For weekly dumps, a set of 5 tapes per dumped file system is used, also on a cyclical basis. Each month, a level 0 dump is taken on a set of fresh tapes that is saved forever. FILES
/dev/rxp0a default filesystem to dump from /dev/rmt0 default tape unit to dump to /etc/ddate old format dump date record (obsolete after -J option) /etc/dumpdates new format dump date record /etc/fstab Dump table: file systems and frequency /etc/group to find group operator SEE ALSO
restor(8), rdump(8), dump(5), fstab(5), dumpdir(8) DIAGNOSTICS
Many, and verbose. BUGS
Sizes are based on 1600 BPI blocked tape; the raw magtape device has to be used to approach these densities. Fewer than 32 read errors on the filesystem are ignored. Each reel requires a new process, so parent processes for reels already written just hang around until the entire tape is written. It would be nice if dump knew about the dump sequence, kept track of the tapes scribbled on, told the operator which tape to mount when, and provided more assistance for the operator running restor. 4th Berkeley Distribution DUMP(8)

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