From the guest vm I can ssh into the trove instance (so port 22 is open and accepting) From the guest vm I cannot reach port 3306 From within the trove instance I can reach port 3306 and mysql is functional It feels like the security group does not allow 3306, but the entry is there (see etherpad) What puzzles me is that netstat in the trove instance does only show listen to 3306 for tcp6 but not for tcp - whereas 22 listens for tcp6 AND tcp root@ms57plain:~# netstat -anp | head -17 Active Internet connections (servers and established) Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name tcp 0 0 127.0.0.53:53 0.0.0.0:* LISTEN 3867/systemd-resolv tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 1074/sshd tcp 0 0 10.9.9.126:22 10.9.9.128:60126 ESTABLISHED 9412/sshd: root@pts tcp 0 0 10.10.10.84:54326 10.0.0.120:5672 ESTABLISHED 1002/python3 tcp 0 0 10.9.9.126:22 10.9.9.128:57880 ESTABLISHED 9021/sshd: root@pts tcp 0 0 10.10.10.84:44266 10.0.0.120:5672 ESTABLISHED 1002/python3 tcp6 0 0 :::3306 :::* LISTEN 4881/mysqld tcp6 0 0 :::22 :::* LISTEN 1074/sshd udp 0 0 127.0.0.53:53 0.0.0.0:* 3867/systemd-resolv udp 0 0 10.10.10.84:68 0.0.0.0:* 3850/systemd-networ udp 0 0 10.9.9.126:68 0.0.0.0:* 3850/systemd-networ raw6 0 0 :::58 :::* 7 3850/systemd-networ raw6 0 0 :::58 :::* 7 3850/systemd-networ So how can I reach from within the 3306 at all? Does docker interfere here?