Using calibre on 2 computers at the same time

[chaley]

Originally Posted by JSWolf

One thing I am doing is using a mapped network drive. Maybe most of the problems are trying to use a network drive not mapped as a standard drive letter and trying to use the network name.

Possibly, although from the point of view of the network server what happens at the network level for UNC names and mapped drives is indistinguishable. My assertion could be wrong if both ends run similar versions of Microsoft SW, as Microsoft might be "optimizing" something.

[theducks]

The OFFICIAL line (see the FAQ) is: No.
(because they are unpredictably unreliable and systematically fragile to use with Calibres Library Structure. )

We have heard those famous words: "It used to work! and now, I have lost my Library", many times.

As a Calibre Mod, I will stick to recommending the SAFER practice.

ALWAYS.

[sadievan]

Originally Posted by eschwartz

You could consider storing your library in Dropbox or using BitTorrentSync or something to duplicate your calibre library across multiple machines. The important thing is, you must makes sure to sync all changes before opening calibre or you can have edit clashes which move things around randomly. Also, never sync while calibre is running.

Do you 'pause' Dropbox syncing before opening up Calibre?

[eschwartz]

Originally Posted by sadievan

Do you 'pause' Dropbox syncing before opening up Calibre?

Yes indeed.

Actually, it is even more secure to do a one-way mirror sync from your calibre libraries to their Dropbox backup, which renders that redundant, but...

Anyway, my workflow:

1. pause dropbox.
2. start calibre. Library is stored outside Dropbox.
3. stop calibre.
4. rsync script copies changes from calibre libraries to the Calibre Libraries folder in Dropbox
5. start dropbox, sync all changes using the redundant clone

[JSWolf]

Originally Posted by chaley

Possibly, although from the point of view of the network server what happens at the network level for UNC names and mapped drives is indistinguishable. My assertion could be wrong if both ends run similar versions of Microsoft SW, as Microsoft might be "optimizing" something.

The desktop that hosts the drive is running Windows 7 and the other two that access the libraries remotely are running Windows 8.1.

[sadievan]

Originally Posted by eschwartz

Yes indeed.

Actually, it is even more secure to do a one-way mirror sync from your calibre libraries to their Dropbox backup, which renders that redundant, but...

Can you explain how you do this.

Anyway, my workflow:

1. pause dropbox.
2. start calibre. Library is stored outside Dropbox.
3. stop calibre.
4. rsync script copies changes from calibre libraries to the Calibre Libraries folder in Dropbox
   

1. Can you also explain. Wouldn't it automatically sync when you unpause Dropbox?
   
   

   start dropbox, sync all changes using the redundant clone

Wouldn't this be the same as your rsync script comment??

Thanks

[eschwartz]

Originally Posted by sadievan

Can you explain how you do this.


Can you also explain. Wouldn't it automatically sync when you unpause Dropbox?



Wouldn't this be the same as your rsync script comment??

Thanks

I use rsync on linux -- though Windows tools like FreeFileSync would work as well -- to create a one-way "mirror" copy of my Calibre Libraries folder. The mirror copy goes in Dropbox, and the main libraries folder remains canonical no matter what.

Then Dropbox syncs the mirror, and if it becomes unhappy and eats my library in edit clashes, the synced backup is overwritten anyway.

A complete backup regime is actually more complicated, because it involves a rotating snapshots hardlinked setup à la Apple Time Machine, but this is the simple version.

[chaley]

@eschwartz: won't this fail if you edit your library sequentially on two machines? There seems to be no back-sync from dropbox to calibre, so machine A will never see machine B's changes and vice versa. The last machine to touch the library wins. Or am I missing something?

[sadievan]

Originally Posted by eschwartz

I use rsync on linux -- though Windows tools like FreeFileSync would work as well -- to create a one-way "mirror" copy of my Calibre Libraries folder. The mirror copy goes in Dropbox, and the main libraries folder remains canonical no matter what.

Then Dropbox syncs the mirror, and if it becomes unhappy and eats my library in edit clashes, the synced backup is overwritten anyway.

A complete backup regime is actually more complicated, because it involves a rotating snapshots hardlinked setup à la Apple Time Machine, but this is the simple version.

It seems I remember somebody posting something similar about using a link to point Dropbox to a local folder.

As far as backups go, I presently am keeping my Calibre library on Dropbox. After I add any books or update anything in Calibre, I back it up to a flash drive. My computer is also backed up (Dropbox included) every night to an external HD.

[sadievan]

Originally Posted by chaley

@eschwartz: won't this fail if you edit your library sequentially on two machines? There seems to be no back-sync from dropbox to calibre, so machine A will never see machine B's changes and vice versa. The last machine to touch the library wins. Or am I missing something?

That is what I was thinking also.

[eschwartz]

Originally Posted by chaley

@eschwartz: won't this fail if you edit your library sequentially on two machines? There seems to be no back-sync from dropbox to calibre, so machine A will never see machine B's changes and vice versa. The last machine to touch the library wins. Or am I missing something?

That is indeed my intent. I use dropbox for mobile access and redundant backup, not for syncing between multiple computers.
I will consider updating my setup just as soon as I get another computer, and intend to edit it from there.

[sadievan]

Originally Posted by eschwartz

That is indeed my intent. I use dropbox for mobile access and redundant backup, not for syncing between multiple computers.
I will consider updating my setup just as soon as I get another computer, and intend to edit it from there.

So are you saying you have 2 DIFFERENT Calibre Libraries on 2 different machines? Why do that if they are not in sync. What am I missing.

[sadievan]

Originally Posted by theducks

The OFFICIAL line (see the FAQ) is: No.
(because they are unpredictably unreliable and systematically fragile to use with Calibres Library Structure. )

We have heard those famous words: "It used to work! and now, I have lost my Library", many times.

As a Calibre Mod, I will stick to recommending the SAFER practice.

ALWAYS.

Do you use a system similar to eschwartz to sync with a cloud service such as Dropbox?

I would sure hate to lose all my books.

[eschwartz]

Originally Posted by sadievan

So are you saying you have 2 DIFFERENT Calibre Libraries on 2 different machines? Why do that if they are not in sync. What am I missing.

Did I not just say I have only one machine? The Dropbox copy is currently read-only. If I decide I need to sync from multiple machines, I will change my methods.

It is also useful if someone plans to do work on one machine but wants it accessible elsewhere, or possibly share wih family, but doesn't want them to change anything.

Oh, yeah. I also access the dropbox library read-only from a school Windows computer, but that isn't where I edit stuff.

[sadievan]

Originally Posted by eschwartz

Did I not just say I have only one machine? The Dropbox copy is currently read-only. If I decide I need to sync from multiple machines, I will change my methods.

Well I guess I need to polish my reading skills. LOL Sorry about that.

Do you know of any known problems if I create a link/shortcut to my Calibre folder in dropbox. Or is it better to just use a sync program to 'backup' Calibre to Dropbox.