Tar and Taper for Linux
There is a special preference that applies only to SCSI drives. This is the --block-size option. The SCSI kernel tape driver expects data to be presented to it in blocks of a maximum size—the default is 32K. For this reason, taper writes data in blocks of 28K by default. However, should you wish to change that, you can do so with the [cw]--block-size[ecw] optioni—for example, some tape drives may function more optimally if data is written in blocks of, say, 64K. Note that this must be less than the SCSI kernel tape driver's maximum size.
You can change this option for non-SCSI drives, but it won't really affect performance.
There is no distinction between file sets made in restore and file sets made in backup—they can be used interchangeably.
To make a file set, enter backup or restore and select the files and directories you wish to designate as your file set. Then press B and taper will prompt you for a name to give to the file set. After you enter the name, the file set will be saved.
Next time you wish to backup this particular file set, press L in backup or restore, and taper will show you a list of the file sets it knows about. Select one using the arrow keys and ENTER. This particular file set will then be loaded.
taper was designed to make backing up your Linux file system easy and painless. The traditional Unix utilities, tar and cpio, are very powerful, but they are not very user friendly. With Linux becoming more popular with non-hackers, another backup solution was badly needed. I hope taper fills this gap.
There are times, however, when you should use tar rather than taper. They are:
When you will be doing backups on one UN*X system and restores on another—e.g., you make a backup on your Linux system and you restore on a Xenix system. As yet, taper has not addressed cross-platform archive compatibility—it may work, but it is not guaranteed. If you do wish to use taper to do this, test it thoroughly first.
If you need to do remote file accessing—e.g., need to access files on host:/directory. taper does not support this yet, and it may be a while before it is added.
Software developers distributing their programs as source files are still better off using tar because to distribute as taper files means also having to distribute the archive information file, which the end-user would have to place in the ~/.taper_info directory—another step confusing to novices.
Unless you are in one of those situations, taper should be adequate for most of your needs. It is certainly easier to use than tar and cpio.
As this product is under development, suggestions, bug-fixes, comments, etc. are all welcome. Similarly, short messages saying that taper works for your system are greatly appreciated since it gives me an idea of how many people are using taper and what sort of hardware it works on. This can allow me to help other people who have similar hardware.
Yusuf Nagree is a part time doctor and a full time Linux hacker (aargh—sorry, full time doctor and part time Linux hacker). He has been a computer buff since his dad bought him a ZX-80 in 1980 and has had various computers over the years. Bored with DOS, OS/2 and Windows, the aspect of Linux he finds most enjoyable is the community spirit and general willingness to help and share knowledge and experience.
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