I have a server with 8GB of disk space running MongoDB. It collects 250,000 documents a day (spread across three collections), so the 8GB is only enough to last it maybe a week or so before I have to push the documents periodically to a server with more space. Unfortunately, the machine isn't online 95% of the time and connecting it to a dedicated MongoDB server with more disk space isn't an option either.
My current approach is to connect to the machine every few days, transfer all of the documents, and wipe the database, but that seems a little dangerous and hacky.
I looked into replication, but that will still have the disk space problem and from what I can tell. Sharding won't work either, as I'd like to maintain a complete duplicate of the database on at least the computer that I store the full database on.
Does MongoDB have any features that I overlooked that can work for this scenario? Maybe some sort of read/write buffer that can be flushed?