Debian see's a Kindle Fire as a mtp device1, so you have to mount it as
jmtpfs /media/boudiccas/k2 where k2 is
your device name, which then says -
Unable to read MTPZ public exponent from ~/.mtpz-data, MTPZ disabledDevice 0 (VID=1949 and PID=0007) is a Amazon Kindle Fire (ID1).
PTP_ERROR_IO: failed to open session, trying again after resetting USB interface
LIBMTP libusb: Attempt to reset device
and it mounts it to "/media/boudiccas/k2" which you can verify by opening it in your file manager, which then shows "/media/boudiccas/k2/Internal storage".
From here you are supposed to be able to rsync or obnam backup, except that you get loads of errors which make it virtually unusable.
So how do you get it so that you can access the file system on the kindle fire? I've tried using "airdroid", an android app on the kindle, but this didn't work for me.
The solution is to use an android app called "ftp server", and with the kindle fire connected to your computer using a USB cable, start "ftp server" on the kindle, and it will display on the screen something like this -
Anonymous user enabled
Then on your computer you need to start "krusader", and use "New net connection" and put the above ftp details into the popup window, and it will connect to the kindle fire and its familiar file-tree. From here on you can transfer over books to whatever directory that you want.
You can verify that they have transferred successfully by them appearing on the carousel of the kindle. Success!
By using "krusader" you can transfer files across anonymously and delete files on the kindle fire, if you try using "filezilla" it won't allow you to delete any files nor transfer files over. It is the same if you try using "gFTP".
mtp: "media transfer protocol", a MS-windows specific protocol. ↩