03-29-2010, 10:27 AM | #31 |
Wizard
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I will always keep an SD and mini hard-drive backup of my library. Octuple redundancy.
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03-29-2010, 10:45 AM | #32 | |
Wizard
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I wasn't really trying to say don't use dropbox - it looks like a great option, it just needs to be used with some care and knowledge. There's always risk - your hard drive may blowup, too, so the advantages of dropbox can easily outweigh the relatively minor risk. I'd be more tempted if my my library would fit in the free space. Last edited by Starson17; 03-29-2010 at 11:00 AM. |
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03-29-2010, 10:53 AM | #33 | |
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I probably shouldn't even be discussing this, as I'm sort of guessing how dropbox works, but usually, the cloud holds a copy, and you point that copy to a directory on each machine. If a file gets updated in the monitored directory, the cloud sees that, it pulls a copy into the cloud and sends the updated file to all computers. That means that if you get a corrupted metadata.db file on any one computer, that corruption gets replicated to all. There are two issues. The first is preventing corruption. Avoiding simultaneous use of Calibre on two computers goes partway to doing that, but as I posted, it isn't enough. A batch file launch with a dummy flag file can also help. The other issue is having a backup to recover from when/if a corruption gets replicated to all monitored directories. Don't expect a local copy to be a backup if that local copy is being monitored and updated by dropbox. Last edited by Starson17; 03-29-2010 at 10:58 AM. |
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03-29-2010, 11:03 AM | #34 | |
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Until BOb enlightened me I did have additional full copies of my library on all machines (Desktop = original + Dropbox, Laptop = Copy + Dropbox, Netbook = Copy + Dropbox). Now I've dropped the copies on my Laptop and Netbook (Desktop = original + Dropbox, Laptop = Dropbox, Netbook = Dropbox). My Desktop is backed-up constantly by Carbonite as well (and my Kindle 1 still holds all my Kindle books plus an FTP copy on my personal website that get updated occasionally). |
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03-29-2010, 11:15 AM | #35 | ||
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Quote:
Quote:
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03-29-2010, 11:18 AM | #36 | |
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BOb |
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03-29-2010, 11:21 AM | #37 |
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Correct - it just uses the new library. If there's a metadata.db file there, it just uses that. I keep a small library for testing changes to the Calibre code and my normal one and switch between them several times a day. (My wife gets annoyed if I don't leave the main one open when she wants access to her news and books.
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03-29-2010, 11:31 AM | #38 | ||
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To quote myself: Quote:
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03-29-2010, 11:35 AM | #39 | |
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Cloud based sync programs can't update changes to or from the laptop if the laptop hasn't got a connection to the cloud. If you work on the laptop when you don't have an internet connection (as someone said they wanted to do so they didn't need to rely on the built in content server), those changes don't appear on any other dropbox machine. They sit on the laptop until it gets connected to the cloud. If the owner comes home and works on Calibre there, you've got a conflict at the least. If you're working on Calibre at home and someone turns on the laptop, the home version may have changes in memory, just as dropbox tries to update the home copy of metadata.db as the laptop comes online. I suspect that will lead to corruption for the same reason that running two version of Calibre at the same time will. Someone here (you?) said it posted a "conflicted" copy in the first situation. That's what I would expect, and it's a help. You could rename the conflicted copy of metadata.db, export the opf file for missing records, switch back to the other metadata.db and import to recover the lost data. A corruption would be more of a problem, and that could end up being replicated to everything. As I said, I'm not trying to denigrate dropbox. It just needs to be used with some care and knowledge. Do you have any reason to believe it doesn't work as I described? |
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03-29-2010, 11:45 AM | #40 | |
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Again, I'm not saying don't do this. It's really convenient. Just be aware that the risk is slightly increased. You have to judge if that risk is worth the convenience. Use it wisely. Know that if you've made changes on your laptop or home computer, they need to have a connection to the web, and dropbox needs to be responding and have time to receive those changes and send them to the next computer in the chain before you start working on that next computer. Be cautious about firewalls blocking access to dropbox. Think about daylight saving time changes that may change the dates on two different computers. Don't rely solely on a backup of your computer made yesterday if that's just a backup of the dropbox account. Make a separate backup of a good and complete copy of the Calibre library, or at least the metadata.db file, which is the most important file in Calibre. |
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03-29-2010, 11:45 AM | #41 | |
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The worst case we encountered happened in an eclipse java project. A person in Italy and a person in the UK each changed a different fundamental class at (more-or-less) the same time. The change caused the regeneration of a large number of .class files . The result: because of dropbox propagation delays some files came from Italy and some came from the UK. Nothing worked. We had to get on the phone, stop one of the people, regenerate, then let dropbox propagate. Then do the same thing in Italy. Once everything was back in sync, we could continue to work on our individual parts. |
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03-29-2010, 11:47 AM | #42 | ||
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I mean, it is robust in that if it sees that the file it has a change for doesn't match the same base that it got the change from it won't apply the change. So... the corruption you are concerned about won't happen. Sure... they will get out of sync and you will have to remedy it. Quote:
https://www.dropbox.com/help/36 BOb |
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03-29-2010, 11:53 AM | #43 | |
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I feel like the guy throwing cold water on everyone, when all I want to do is make sure that anyone who's doing this has some idea of how it works so they can avoid problems. |
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03-29-2010, 12:04 PM | #44 | ||
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Maybe I worry too much and corruption isn't an issue. Maybe Calibre locks all files early enough that dropbox would never step on any of the parallel threads Calibre has running. I just don't know. Are you sure you do? Quote:
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03-29-2010, 12:05 PM | #45 | |
I'm Super Kindle-icious
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This year I'm trying to read more of the freebies I've collected over the past couple of years, most have already been converted or don't need conversion as they are Kindle books (I keep DRM stripped versions in Calibre but I read the DRM'd versions on my Kindles). I can still drag and drop those books onto my computer from Windows Explorer without opening Calibre. |
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