I'm not on the design side, but, I'll answer anyway.
All record documents received during project closeout are immediately stored on our server. This server has write permissions for only three people, the majority are accessing read-only.
IT handles nightly backups onsite in our data center. I don't know about the off-site backups, as that's not my department.
Projects are filed by building, then ordered by date and floor.
(Data from said projects is also copied over to composite sets for each discipline, which are the live documents that are updated throughout the life of the building, but, obviously, the original sets are never modified. There are no specific technological restrictions in place preventing that, it's just something we don't do.)
There is an access database listing the files, but, most folks don't bother with it, they'll either browse by hand or use the windows explorer search.
That all depends on what the end goal is. We are required to keep all of our documentation for 10 years after we no longer have the ship in our fleet. We have set up a share called Archives, and when a ship is delivered to us, we archive the final delivery documents and any owners work into that shared drive. Only 4 people have read/write access, but everyone else has read/execute. This allows us to do studies, and anything else with the base information, but it cannot be changed. We also are working on a change process on how we update these archives (as a ship may be changing things while in service), and making sure what we have reflects the existing conditions is a Class regulation. We've found that this works very well, as we always have the original data available as a starting point.
There are any number of ways to archive, but you need to ask yourself, what are my legal requirements, and how long is it reasonable to keep the final set of documents on my server? Once you know that, you can design/plan accordingly.
That's my 2 cents worth,
In addition to any and all information provided here....
You must keep backups on more than one drive/location/media, all the time: simply relying on the 'server' or a backup tape/disk/harddrive is a nightmare/disaster waiting to happen. Some folks also go to the extra step of creating PDFs of all the material in the backup and store it separately as a 'record' set as well: the idea being if an archive fails you always have the neutral PDF 'print' copy to recover/trace over.
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