The server console shows nothing,
and gets closed in a few seconds when using PPPoE.
Folders and files below are not created when the server crashes:
development_behavior_packs, development_resource_packs, internalStorage, world_templates, worlds, valid_known_packs.json

It runs normally when using LAN.
To let other people join my server,
I have to launch the server before dialing PPPoE connection.
This problem does not occur on 1.7.0.13.