fbackup/frecover

[ricky_8]

Hi ALL,

Can we list tape files thru fbackup/frecover tools.As we can do it in tar -tvf to get the contents of the media?

We have a tape which has data stored via fbackup, i want to know the list of files stored on it.

Any idea how to do it?

rgds,

[Sridhar Bhaskarla · Accepted solution]

Hi,

Use frecover with -I option to create an index file. Index file contains the list of all files backed up by fbackup in that archive.

#frecover -I /tmp/index -f /dev/rmt/0m

#pg /tmp/index

-Sri

[ricky_8]

Sridhar,

But then there is no option for list files from media?.
Tar has it (tar -tvf)and fbackup doesnt have that facility?

Rgds,

[Chris Wilshaw]

If you use

frecover -xNvf /dev/rmt/0m -i /

that will read the contents of the tape without attempting to restore them.

You can redirect this to a log file to make it easier to read

frecover -xNvf /dev/rmt/0m -i / > /tmp/fbackup_files 2>&1

[Bill Hassell]

Unlike tar, fbackup only writes to the tape, while frecover will read from the tape. Also unlike classic Unix utilities (tar, cpio, pax, duimp) fbackup builds an index of all the files at the beginning of each tape. Thus, frecover -I will be able to read what was stored on the tape(s) in a few seconds rather than serially reading the entire tape as in tar tvf.

If you want to see if a particular file is on the tape:

frecover -I - -f /dev/rmt/ | grep filename

As mentioned, you can use the -N option as a means to verify the contents of the tape--not a bit-by-bit compare to disk, but a checksum computation and sanity check of the structure of the tape. This is what frecover does during restore operations anyways, so the -N just turns off writing the file to disk.

The concept of a centralized index at the front of the tape is common in all commercial backup programs. Backups are measured in gigabytes today so spinning the tape all the way to the end to find all the filenames is not practical.

The fbackup/frecover pair is designed for high speed access on DDS and DLT media. Special search marks are written after several dozen files (config file controlled) and the position of the most recent search mark is stored in the index. Thus, a file at the end of the tape might take an hour or two to reach with tar, but with frecover, the last file can be restored in a few minutes.

And having an index at the front also allows everey file to have a tape identifier in case the backup requires more than one tape. To locate which tape to insert for some random file, you insert the last tape of the set, run frecover and it will return (after aseveral seconds reading the index) the tape number to insert to obtain the file.

[Jose Mosquera]

Hi,

If your you select the option "-N" you are simulating a recovery in real time without writing in disco,en other words; you will take the equivalent time to a real recovery. As they have already indicated you, a similar functionality doesn't exist to the option "tar -tvf", I recommend you that use the generation of the index in disk through the syntax:

#frecover -I // -f /dev/rmt/

Another possibility is that to the backup's event you redirect the standard output to a specific log file, this way you will always have an index of **real** events (Warnings)during the process of having copied to tape. Of course, in this case you need keep this log for future necessities.

#fbackup [your_fbackup_options] 2>/[your_specific_lof_file]


Rgds.