restor(8)
NAME
restor, 512restor − incremental file system restore
SYNTAX
restor key [ argument... ]
512restor key [ argument... ]
DESCRIPTION
The restor command reads magtapes dumped with the dump command. The key specifies what is to be done. The key option is one of the characters rRxtm optionally combined with f. The 512restor command is used to restore tapes written from 512-byte block file system.
KEYS
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. 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 with the prior volume. Before the restart, however, an icheck -s must be done.
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. First, mount volume 1 of the set of dump tapes. Then, invoke the restor command. The restor command announces whether or not it found the files; given the number, it names the file and rewinds 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 recommended procedure is to mount the last through the first volume in that order. The 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.
s Uses the specified number (next argument) as the tape dump file from which the file system or each named file is to be restored. This option is to be used when there are multiple dump files on a single tape. For example,
restor xsf 2 /dev/rht1 pro.text
restor rs 3
The first extracts the file “pro.text” from the second tape dump file. The second restores the complete file system from the third tape dump file.
t Print the date the tape was written and the date the filesystem was dumped from.
m Micro/PDP-11, restor from RX50 floppy diskettes instead of magtape. The r option must accompany the m option. For example:
restor rmf /dev/rrx2 /dev/rrd0
To allow an interrupted restor to be restarted with the prior volume, restor asks for the starting volume number. Before an interrupted restor may be restarted, an icheck -s must be done on the file system.
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. For example,
/etc/mkfs /dev/rhp03 40600
restor r /dev/rhp03
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.
RESTRICTIONS
There is redundant information on the tape that could be used in case of tape reading problems, but restor doesn’t use it.
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 new-line when the next tape has been mounted.
FILES
/dev/rht0 - default tape unit
rst*