Amazon EC2 örneği bilgisayarımdan SSH ile giriş yapmama izin vermiyor

Uzaktan, dün geceden beri giriş yaptım ve iyi çalışıyordu, sadece zaman aşımına uğradım, şimdi sabah SSH aracılığıyla aynı Amazon EC2 kutusuna tekrar giriş yapamıyorum:

sun@From-SSH-Client-Ubuntu-Box:~/To-SSH-RHEL6.4$ ssh -v -i amazon.pem ec2-user@54.22x.x.x
OpenSSH_6.0p1 Debian-3ubuntu1, OpenSSL 1.0.1c 10 May 2012
debug1: Reading configuration data /home/sun/.ssh/config
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug1: Connecting to 54.22x.x.x [54.22x.x.x] port 22.
debug1: Connection established.
debug1: identity file amazon.pem type -1
debug1: identity file amazon.pem-cert type -1
debug1: Remote protocol version 2.0, remote software version OpenSSH_5.3
debug1: match: OpenSSH_5.3 pat OpenSSH_5*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_6.0p1 Debian-3ubuntu1
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-ctr hmac-md5 none
debug1: kex: client->server aes128-ctr hmac-md5 none
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(1024<1024<8192) sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY
debug1: Server host key: RSA de:83:e8:bf:51:86:30:89:b9:54:13:52:dc:75:a1:df
debug1: Host '54.22x.x.x' is known and matches the RSA host key.
debug1: Found key in /home/sun/.ssh/known_hosts:39
debug1: ssh_rsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey,gssapi-keyex,gssapi-with-mic
debug1: Next authentication method: gssapi-keyex
debug1: No valid Key exchange context
debug1: Next authentication method: gssapi-with-mic
debug1: Unspecified GSS failure.  Minor code may provide more information
Credentials cache file '/tmp/krb5cc_1000' not found

debug1: Unspecified GSS failure.  Minor code may provide more information
Credentials cache file '/tmp/krb5cc_1000' not found

debug1: Unspecified GSS failure.  Minor code may provide more information


debug1: Unspecified GSS failure.  Minor code may provide more information
Credentials cache file '/tmp/krb5cc_1000' not found

debug1: Next authentication method: publickey
debug1: Offering RSA public key: my@gmail.com
debug1: Authentications that can continue: publickey,gssapi-keyex,gssapi-with-mic
debug1: Trying private key: amazon.pem
debug1: read PEM private key done: type RSA
debug1: Authentications that can continue: publickey,gssapi-keyex,gssapi-with-mic
debug1: No more authentication methods to try.
Permission denied (publickey,gssapi-keyex,gssapi-with-mic).