Saturday, November 1, 2008

Interesting Issues With LTO Compatibility

LTO, (Linear Tape Open) http://en.wikipedia.org/wiki/Linear_Tape-Open is becoming a popular backup/archive format, especially for productions that uses tapeless cameras. LTO is the preferred backup/archive format for bonding and insurance companies, so a lot of productions are backing up their dailies to LTO tapes.

The cameras, whether they use portable capture formats like P2, flash cards or hard drives or are tethered to a field recorder like the S Two, need to have the media offloaded and backed up so the recording devices can be reused.

The unfortunate part is that there is no constancy about HOW the media is written to an LTO tape.

Quantum makes an A-Series line of LTO drives that are network-attached, and MXF metadata aware, http://www.quantum.com/Products/TapeDrives/LTOUltrium/LTO-3A/Index.aspx.

At the moment, it's not known if any LTOs written on a A-Series drive can be read on a standard LTO drive without special software. So at the moment, LTO tapes written on an A-series drive need to be extracted off of an A-series drive. My assumption is that the A-series is proprietary to Quantum and no other manufacturer makes them.

This limitation may be fine if these LTO tapes stay in-house or given to someone with an A-series drive, but can be problematic if the tapes are given to someone with a standard LTO drive and can't recognize the tapes.

At the recent HD Expo, I saw a custom P2 field offload/backup/archive system, with an LTO drive build into it. Since the whole system is Windows based, the manufacturer decided to use Symantec Backup as their backup/archive software. Once again, this is fine if the tapes stay in-house or given to someone who is using Symantec Backup, but problematic if given to someone who's not using it.

There is also the dilemma with these proprietary hardware/software is not just compatibility at the present, but compatibility in the future. No one knows if the A-series LTO line and Symantec Backup will be around in 5, 10 or 20 years, let alone backwards compatible with current versions.

Last weekend at a demonstration of the Arri D21 Digital Cinema Camera, the S Two representative, www.stwo-corp.com, mentioned they do their backup/archive to LTO using tar (tape archive) http://en.wikipedia.org/wiki/Tarball.

Tar is common in the Unix/Linux workstation platforms, which has been used in post productions since the 90s. While a lot of post houses have moved to inexpensive desktop systems using Windows, Linux and OS X, and data is being transported by hard drives and secure high speed data lines, the use of tar is still common when delivering a tape based backup/archive, since it's a non-proprietary format.

Tar itself has various flavors and shortcomings, and is far from being the perfect choice for backup/archive. It just happens to be more common.

Until the bonding and insurance companies become more specific on how the LTO tapes need to be written, we will have a variety of formatting.

The only way to make it easier to deal with is proper labeling of how the tape is written, what software, and the contents of the tape. This is the only way of insuring that all the contents of the tape can be properly extracted.