EC2 instance terminated from custom AMI

If every time your instance terminates when you try to launch it from an AMI, the AMI is probably corrupted.

What you need to do is to recreate the AMI from the original instance.

Make sure all processes are turned down except the ssh daemon.

Run netstat -tupln

Active Internet connections (only servers)

Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name

tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      701/sshd

tcp6       0      0 :::22                   :::*                    LISTEN      701/sshd

udp        0      0 0.0.0.0:68              0.0.0.0:*                           491/dhclient3

Make sure only the above processes are running and then create the AMI.