Perhaps this is documented already, but it seems worthy of noting here since it has been causing me about a week (maybe longer) of tumoil. I have a couple of databases that I've built for a client who hosts them on their server (managed by their IT Dept.) with many other FileMaker databases used by their organization. They are running FMS 11 Advanced on a Mac Server.
This past week they reported that a huge amount of data had been lost from one of my databases. In looking into it I found that indeed the last record entered was from June 2012 - they pretty much use this system daily so this is significant. We were able to get all but one day's worth of the data back from a backup. I have spent most of the past three days trying to figure out exactly what happened. I finally requested, and was given, remote access to their server, not just the FileMaker Admin Console. I found that they had multiple occurances of the same file within different folders in FileMaker Server's Databases folder. It looks like when the server was set up they copied data from the old server by copying the folder, then also created a second folder and moved files to that as well. FMS only opens one copy of each file so everything seems hunky-dory when looking at the databases list in Admin Console. And for the most part it seems to function properly although I'm beginning to think some of the performance issue they've had (things just never ran as quickly as I thought they should and they seemed to get disconnected due to network issues more frequently than I usually see) may be due to this.
Here's what I'm now attributing the lost data to based on a review of the logs and backups. They run a nightly backup of the entire directory. On Tuesday night the backup ran as usual and no errors were reported. However, when the databases started back up after the consistency check it looks like a different copy of the file in question was opened. I believe this copy, in a separate folder, had simply been sitting there since June 2012. There didn't seem to be any indication of a problem with the backup and the log shows that the file past the consistency check. Only problem is, I can't really tell from the log which file of the two is being backed up, checked for consistency, etc. because it only gives the file name not the path information.
I'd welcome feedback from others. Does this seem to be a reasonable conclusion based on the information? Is ther something else I should check? Obviously having multiple copies of a file in the databases folder is a long way from a best practice - and something I'd never do. But I don't think I've ever seen documentation indicating that it shouldn't be done. Should FileMaker's backup be "smart enough" to track which file it backed up and which one it should open again when there are two files with the same name? Should this be reported as a bug?