I've just generated a ECDSA key with
ssh-keygen -t ecdsa -b 521
I then proceeded to copy this key to my server:
cat .ssh/id_ecdsa.pub | ssh myserver "tee -a .ssh/authorized_keys"
I've verified that my key is in the file.
However, when I attempt to connect, my connection is rejected:
ssh -v -i .ssh/id_ecdsa myserver
OpenSSH_5.9p1 Debian-5ubuntu1.1, OpenSSL 1.0.1 14 Mar 2012 debug1: Reading configuration data /etc/ssh/ssh_config debug1: /etc/ssh/ssh_config line 19: Applying options for * debug1: Connecting to myserver [192.168.1.1] port 22. debug1: Connection established. debug1: identity file .ssh/id_ecdsa type 3 debug1: Checking blacklist file /usr/share/ssh/blacklist.ECDSA-521 debug1: Checking blacklist file /etc/ssh/blacklist.ECDSA-521 debug1: identity file .ssh/id_ecdsa-cert type -1 debug1: Remote protocol version 2.0, remote software version OpenSSH_6.1 debug1: match: OpenSSH_6.1 pat OpenSSH* debug1: Enabling compatibility mode for protocol 2.0 debug1: Local version string SSH-2.0-OpenSSH_5.9p1 Debian-5ubuntu1.1 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 10:27:b8:78:2c:e1:e3:42:8e:e3:66:c4:cc:4e:f1:c0 debug1: Host 'myserver' is known and matches the RSA host key. debug1: Found key in /home/naftuli/.ssh/known_hosts:73 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 debug1: Next authentication method: publickey debug1: Offering ECDSA public key: .ssh/id_ecdsa debug1: Authentications that can continue: publickey debug1: No more authentication methods to try. Permission denied (publickey).
Found this in the server logs:
auth.info sshd: userauth_pubkey: unsupported public key algorithm: ecdsa-sha2-nistp521 [preauth]
Both my client and the server are using OpenSSH. The server's OpenSSH version is OpenSSH 6.1, my client's OpenSSH version is OpenSSH 5.9.
How can I tell which key algorithms are supported by my server?