Most of the Acceptable Use Policy is common sense, but a few of the prohibited activities are things people set up without realising they are a problem. These are the ones that end services.
Why it happens
Everything on this list either attacks someone else or gets the node's IP addresses blacklisted, which damages every other customer sharing that node.
What to do
- Never run these
Port scanning, botnet hosting, malware distribution and cryptocurrency mining are all prohibited outright and result in immediate suspension.
- Do not try to send email
Outbound port 25 is blocked at the network level, so mail-sending plugins will not work regardless of configuration. Attempting to send spam is a policy violation on its own.
- Watch what your plugins do outbound
You are responsible for what runs on your server, including code you installed but did not write. A plugin that scans ports or relays mail breaks the policy just as much as doing it yourself.
Getting a node IP blacklisted — by Mojang, by Spamhaus or by anyone else — means permanent account termination with no refund, plus liability for the damage caused to the other services on that IP.