I just thought of another diagnostic aid -- trying to connect to the WD client from the linux host. Start calibre, then in a terminal window try
Code:
telnet 127.0.0.1 9090 (or whatever your port is)
The connect should succeed and you should see something like this
Code:
860[9, {"pubdateFormat": "dd MMM yyyy", "currentLibraryUUID":
"05584da8-8c69-4938-874b-3845d2c85c69", "canSupportUpdateBooks": true,
"calibre_version": [3, 13, 0], "validExtensions": ["lrf", "rar", "zip", "rtf",
"lit", "txt", "txtz", "text", "htm", "xhtm", "html", "htmlz", "xhtml", "pdf",
"pdb", "updb", "pdr", "prc", "mobi", "azw", "doc", "epub", "fb2", "djv",
"djvu", "lrx", "cbr", "cbz", "cbc", "oebzip", "rb", "imp", "odt", "chm", "tpz",
"azw1", "pml", "pmlz", "mbp", "tan", "snb", "xps", "oxps", "azw4", "book",
"zbf", "pobi", "docx", "docm", "md", "textile", "markdown", "ibook", "ibooks",
"iba", "azw3", "ps", "kepub", "kfx", "fooper", " gorp"], "timestampFormat":
"dd MMM yyyy", "canSupportLpathChanges": true, "passwordChallenge": "",
"currentLibraryName": "Library.test_small", "serverProtocolVersion": 1,
"lastModifiedFormat": "dd MMM yyyy hh:mm:ss"}]
If you don't then the problem is local to the Linux machine.
You can also try connecting to the visible IP address: 192.168.88.251
If these work then you can try the same thing from your WiFi router. My guess is that this won't work.
If that works then try it from your Android device.