My example, 32775 is mapped to 8080, 32274 to 8081 (you may have different external port numbers of 3xxxxx) 8080 (Full Calibre GUI) and 8081(Calibre content server for OPDS in your Moon+Reader Net Library).

Usually, you need to know 2 of the 3 port numbers, i.e. After you start the Calibre container, go into the 'Details' page of the container, it will show you 3 port mapping numbers (see my attached screenshot). Now, how can you access the full Calibre gui from browser: Calibre will then use your existing ebook library. When you first run your Calibre in Docker (see which port to use below), it will start with Calibre setup wizard and it will ask you where your ebook library is located, click browse, you will see 'nobody/Calibre…' folder, you need to click the arrow up icon till you see the root directory then you will see the folder name you mount earlier, choose it.

If you already have your existing calibre ebook library and want to use it for Calibre in Synology Docker, you have to map your existing ebook library to Calibre Docker in Syno by going into the Volume tab (see screenshot attached), click 'add folder', under File/Folder column, search and select your existing ebook library folder (for me, it is a shared folder named 'Calibre_Library' in my Synology) then under 'Mount Path' column, you name a folder name you want (any name) starting with '/' then save. How do I see if it is working? What address do I use to access it from the internet? Been trying to figure this out all week! I want to be able to set Moon Reader + to see it as a net library and have friends use it as well. Docker is installed, image is downloaded and installed, container created. I cannot figure out where to go from here.

I used Calibre in Windows 10 to create the library there. This is where I fall apart! I have my Library on my Synology server, in a folder called Library and a sub folder Ebooks.

Calibre server synology