[plug] Bitrot

[Hooker]

On Sun Dec 23 19:03 , Adrian Chadd  sent:
>
>So if you want to rebuild the whole application you need to have
>
>* the application;
>* the libraries the application uses;
>* the compiler suite the application uses;
>* the dependencies from -those-;
>* the operating system code;
>* and the depedencies which that requires;
>
> start to see the difficulty? :) Lets not talk about hardware to read
>backups or deal with old hardware. I'm sure some people here have a
>story or two to talk about old hardware which is still in use but
l>ast shipped with drivers for Linux 1.2.13...

In a previous life I worked for BNFL in the UK - the guys who designed nuclear power stations, and they had a serious problem with archival storage. All the designs had to be available for 30 years after the expected close down date of each station, and almost all of it was electronic. So, they mothballed 2 examples of each of the specialised CAD machines that they used, complete with spares, maintenance manuals and so on.

Multiple copies of the data was written to mag tapes (those 10.5" mainframe tapes that look so dated now) and every 6 months they were retensioned. The plan was that the tapes would be copied every 5 years to new media and the old media destroyed.

It cost a lot, but decomissioning costs are so huge anyway that no-one really noticed.

Yes, you're right, long term data storage is a major problem that's really only fixable with money and effort.

Hook