Author Archives: Michael Richmond
Problem with video-stream playback in OS X Lion (10.7)
My home IT infrastructure includes an Apple Mac Mini computer that is used as our media server and primary playback machine. The Mac Mini is connected to a 1080p LCD Television, 1GB LAN, and accesses a NAS for media storage. … Continue reading
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
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
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
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
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
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
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
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
A filesystem for tape? Why?
Tape has been around forever[1. At least since 1951 starting with the UNIVAC 1. Certainly longer than silicon transistors and modern digital computers.]. Generally, there has been no change in the way that people and applications work with tape since … Continue reading