The proxy is being flooded with connections
Applies to BungeeCord, Velocity.
What it looks like in your log
Too many connections
What causes it
A connection or ping flood is hitting the proxy, which is what bot attacks look like in the log.
How to fix it
Enable the proxy’s connection limits or an antibot layer, and rate limit at the edge (a protective frontend such as TCPShield helps).
Not sure this is your problem? Paste your log and Roastd will tell you which of these it actually matched, and what else it found.
Check your own log