Keeping book on NAS but metadata.db on local (Ubuntu)

[q345]

Hi Richard !

Here is my settings: ( I don't run Windows, I have Win XP as dual-boot but I use it very infrequently only where I have no choice).

Dell Studio XPS desktop, with Ubuntu 10.04 Lucid
Dlink DNS-323 NAS with 2 hard drives each is 1T (very common NAS, nothing specific about it, run few services including FTP server)

They are connected via Dlink Gigabit switch (and I have pretty standard wired/wireless router)

The directory on NAS where I keep my multimedia files - music, photo, videos, e-books etc, backups and everything I need to access remotely and/or without desktop turned on is mounted by 'mount -t cifs'

I've never ever have any problems with any application (digital music, photo browsers, digital video etc to access this mounted directory. Amarok music player uses mysql and I handles my quite large music collection - hundreds of CD in FLAC with no problems).

So that, when I tried , immediately after installing Calibre and adding couple of books, to change library location I was unpleasantly surprised it failed ( I tried few times)
I checked the Google and found few people complains about it and, including this forum and I remember quite well that in of the threads Kovid mentioned
'IIRC sqlite doesn't support NAS' . On sqlite website I remember it was something about locking problems in NFS.

So then I published the questions and Toddos's advise solved all the problem
(After I saw it I downloaded source tree and found myself all those environmental variables).

As you can see, I don't use any fancy devices/apps/settings - my set-up is very standard and used by huge amount of home users. I've never used WHS and I don't know what is the difference. I don't leave Calibre running all the time. I open it add the book, convert it if I need and close it. If I need to read book on my Palm TX I just bring file using FTP from NAS (Palm TX has a nice little FTP client built into one of the third party file browsers - Resco Explorer). That's about it. Google 'Sqlite NAS', see ramblings by yourself. As I mentioned, mysql works perfectly fine (for other collection maintainers). If you have any ideas/guesses, I'll appreciate your input

May be WHS use different protocol. I can't see any other reasons. Here is the description of cifs protocol I use (it's just a version of MS SMB)

------------------------------
Microsoft CIFS: Common Internet File System protocol

The Common Internet File System (CIFS), an enhanced version of Microsoft Server Message Block (SMB), is the standard way that computer users share files across intranets and the Internet

[kovidgoyal]

@q345: there are many netwoked filesystems out there. SOme support file locking, some don't. Yours doesn't. For linux I would suggest using sshfs instead as IIRC it supports file locking.

[q345]

Kovid, thanks for the advice

I might try 'mount -t sshfs' and see if it solves the problem. One issue is that I have many apps running which use this mounted directory and I don't know if they will be OK with it, but I'll try it sometimes next week. ( For instance I initially had problems with Logitech Squeezebox when I mounted NAS drive with -t tifs, so I've changed it per recommendation on the Slimdevices forum to -t cifs and it works fine now, so I am trying not to break things)

Regards

[q345]

I've never learned/used Python, but I played a little bit with interpreter today
and found out that method os.path.ismount(directory_name) return True if directory is mount point.

May be it's make sense to test the new library location for "mountpoitness" if user try to change it in Preferences and issue a warning :

"The new library location is a mountpoint !
Please, check if it supports file locking"

Should take just a few lines of code

Same test should be done when Calibre is started, since when I tried to "cheat" by converting Calibre Library directory to mountpoint when Calibre was not running, results were disastrous.