Category Archives: data storage

Bridging ExpressCard to PCIe for LTO

In the mid-1990’s I worked as a photoshop jockey for the Sydney Morning Herald and other Fairfax Media newspapers. At that time we would regularly send a photographer into the field with a large Pelican case that held a digital … Continue reading

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LTFS Format Specification and Open-Source

In an earlier post I mentioned that prior to the introduction of LTFS an application typically relied on proprietary APIs to read and write data tape. These proprietary APIs typically have used proprietary data formats on the tape media. These … Continue reading

Posted in data storage, LTFS, open source, specification | 4 Comments

Filesystem recovery examples with ltfsck

In addition to the filesystem implementation, the Linear Tape File System (LTFS) software ships with two core utilities, “mkltfs” and “ltfsck”. mkltfs (pronounced “make LTFS”) is used to format LTO cartridges with the LTFS Format. ltfsck is used to check … Continue reading

Posted in data safety, data storage, LTFS | 2 Comments

LTFS consistency and Index snapshots

An LTFS Volume must be in a consistent state when the volume is exchanged with another LTFS system. The LTFS Format Specification defines consistent state as: “A volume is consistent when both partitions are complete and the last Index Construct … Continue reading

Posted in data safety, data storage, LTFS, resiliency | 3 Comments

Can you use LTFS on LTO4 or earlier media?

I have noticed a pattern of Google searches related to the question “Can LTFS be used with LTO4 media?”. This question is implicitly answered in other posts but the frequency of the Google searches motivate me to post the following … Continue reading

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sync() behavior in LTFS

Modern operating systems typically maintain an in-kernel cache of file-system metadata and small buffers of recent writes to open files. The file-system metadata typically includes data such as the filename, timestamps, and permissions for recently accessed files and directories. This … Continue reading

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How does LTFS work?

The Linear Tape File System (LTFS) relies on support for partitioning was introduced in LTO generation 5. Partitioning a LTO5 cartridge divides the media in two separate data storage areas known as “partitions”. Each partition can be written to without … Continue reading

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Partitioning in LTO5 and LTFS

The LTO5 specification includes support for partitions on LTO5 data tapes. This partition support can be classified into two groups: Partition Aware and Partition Enabled. Here is the relevant definition from the LTO 5 specification: “All Generation 5 LTO Ultrium … Continue reading

Posted in data storage, LTFS | 3 Comments

Early adopter reports on experience with LTFS

I have been working with Thought Equity Motion from very early in the LTFS productization effort. They amass very large data archives and their CTO, Mark Lemmons, was particularly excited by LTFS from a very early stage. Last year at … Continue reading

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Tape Partitioning and LTFS

Tape partitioning has been introduced over the years to a number of data tape products. Generally, this partitioning support has been under-utilized, or not-utilized by users and applications. For example, DDS tape has supported partitioning since DDS-2 released in 1993. … Continue reading

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