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Have you experienced that you inadvertently overwrote the file saved on the tape given by someone else? LTFS can save you from such unhappy situations.

1. What is LTFS?

Linear Tape File System (LTFS) is a file system developed for LTO and has technology that enables intuitive access to LTO as OS file systems. Before LTFS was born, you had to use special tools to read saved files. Today you can read and write files easily on tapes such as ordinary HDDs or USB memories without special tools thanks to LTFS. Also, LTFS can save the data automatically. This is additional good point in case of inadvertently overwriting.

2. You can Read Old Files with LTFS

LTFS can save both meta-information including the name of files or the written position in the tape and the entire data of files. The save style is write-once type and there are the old index, meta-information, and the old entire data of files on the tape without overwriting. You can read old files with these features. Actually, vendors developing LTFS provide tools and mechanisms to read old files without complicated knowledge.

3. Storing Indexes

There are important points to restore old files. When you use LTFS, you need to save the index after saving the file. LTFS can records meta-information and restart to read files at the position of the saved index. The LTFS vendors prepare various implementations and options. Using implementations or options, the indexes are saved automatically not only when retrieving the tapes from the tape drives but also once every fixed times or the time you finish write the data.

4. Can We Restore the Files in the Tapes Given by Others?

When you accidentally overwrote the files on the tape given by the other person, the tape has already saved the index because the latest index is saved when tapes are taken out from tape drives. Therefore, even if you inadvertently overwrote the file, you can read previous data by using the old index.

*Appendix : The Applicable Standards and OS with LTFS