amazon web services - AWS EC2 Connection closed by when trying ssh into instance

Question

Recently I set up a new EC2 instance. The next day I was not able to connect to my instance via ssh. I could connect and disconnect the day before, I am sure I did nothing. Here is ssh debug info:

ssh -i webserver.pem -v ubuntu@my.elastic.ip
OpenSSH_5.9p1, OpenSSL 0.9.8r 8 Feb 2011
debug1: Reading configuration data /etc/ssh_config
debug1: /etc/ssh_config line 20: Applying options for *
debug1: Connecting to my.elastic.ip [my.elastic.ip] port 22.
debug1: Connection established.
debug1: identity file webserver.pem type -1
debug1: identity file webserver.pem-cert type -1
debug1: Remote protocol version 2.0, remote software version OpenSSH_5.9p1 Debian-5ubuntu1.1
debug1: match: OpenSSH_5.9p1 Debian-5ubuntu1.1 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.9
debug1: SSH2_MSG_KEXINIT sent
Connection closed by my.elastic.ip

Is there a way to resolve this issue? Or shall I reinstall my instance again?

PS rights to my .pem are set to 600.

Answer 1

My problem was that the username was incorrect. On ubuntu instances it should be "ubuntu" and on amazon instances it should be "ec2-user".