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I try to set up a passphrase to access my server with ubuntu server 16.04

Here is what I did (sorry comments are not in English):

Sécuriser SSH : 
Créer 1 administrateur 
# adduser admin962 
L’ajouter aux groupes sudo et ssh 
# adduser admin962 sudo 
# adduser admin962 ssh 
Modifier la configuration de SSH (interdire root, modifier le port et autoriser uniquement le groupe sudo) 
# nano /etc/ssh/sshd_config 
AllowGroups sudo 
Port 4029 
RSAAuthentication yes 
PubkeyAuthentication yes 
décommenter AuthorizedKeysFile 
Redémarrer le service SSH 
# service ssh restart 
Se déconnecter 
# exit 
Créer un jeu de clés (clé publique et clé privée) sur le client 
$ ssh-keygen -t rsa -b 4096 -C admin962@vps307796 
Faire entrée et choisir la passphrase 
Copier la clé publique du client sur le serveur 
$ ssh-copy-id -i ~/.ssh/id_rsa.pub admin962@vps307796.ovh.net -p 4029 
Se connecter avec admin962 et saisir le mot de passe (tester avec une nouvelle fenêtre) 
$ ssh admin962@vps307796.ovh.net -p 4029 
Droits des dossiers 
$ chmod go-w ~/ 
$ chmod 700 ~/.ssh 
$ chmod 600 ~/.ssh/authorized_keys 
$ ssh-add 
Recharger le service SSH 
$ sudo service sshd reload 
Se déconnecter 
# exit 
Se connecter avec admin962 et saisir la passphrase (tester avec une nouvelle fenêtre) 
$ ssh admin962@vps307796.ovh.net -p 4029 
Modifier la configuration de SSH (refuser les mots de passe) 
$ sudo nano /etc/ssh/sshd_config 
PermitRootLogin no 
PasswordAuthentication no 
UsePAM no 
Redémarrer le service SSH 
$ service ssh restart 
Se connecter avec admin962 et saisir la passphrase 
$ ssh admin962@vps307796.ovh.net -p 4029

By following the steps above, when I connect the message appears :

Agent admitted failure to sign using the key.
Permission denied (publickey).

And in detail :

debug1: Reading configuration data /etc/ssh/ssh_config 
debug1: /etc/ssh/ssh_config line 19: Applying options for * 
debug1: Connecting to vps307796.ovh.net [137.74.174.65] port 4029. 
debug1: Connection established. 
debug1: identity file /home/phablet/.ssh/id_rsa type 1 
debug1: key_load_public: No such file or directory 
debug1: identity file /home/phablet/.ssh/id_rsa-cert type -1 
debug1: key_load_public: No such file or directory 
debug1: identity file /home/phablet/.ssh/id_dsa type -1 
debug1: key_load_public: No such file or directory 
debug1: identity file /home/phablet/.ssh/id_dsa-cert type -1 
debug1: key_load_public: No such file or directory 
debug1: identity file /home/phablet/.ssh/id_ecdsa type -1 
debug1: key_load_public: No such file or directory 
debug1: identity file /home/phablet/.ssh/id_ecdsa-cert type -1 
debug1: key_load_public: No such file or directory 
debug1: identity file /home/phablet/.ssh/id_ed25519 type -1 
debug1: key_load_public: No such file or directory 
debug1: identity file /home/phablet/.ssh/id_ed25519-cert type -1 
debug1: Enabling compatibility mode for protocol 2.0 
debug1: Local version string SSH-2.0-OpenSSH_6.7p1 Ubuntu-5ubuntu1.4 
debug1: Remote protocol version 2.0, remote software version OpenSSH_7.2p2 Ubuntu-4ubuntu2.1 
debug1: match: OpenSSH_7.2p2 Ubuntu-4ubuntu2.1 pat OpenSSH* compat 0x04000000 
debug1: SSH2_MSG_KEXINIT sent 
debug1: SSH2_MSG_KEXINIT received 
debug1: kex: server->client aes128-ctr umac-64-etm@openssh.com none 
debug1: kex: client->server aes128-ctr umac-64-etm@openssh.com none 
debug1: sending SSH2_MSG_KEX_ECDH_INIT 
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY 
debug1: Server host key: ECDSA 3f:a2:b6:45:3c:9b:e5:f8:e1:53:fb:fb:8c:21:46:52 
debug1: Host 'vps307796.ovh.net' is known and matches the ECDSA host key. 
debug1: Found key in /home/phablet/.ssh/known_hosts:1 
debug1: SSH2_MSG_NEWKEYS sent 
debug1: expecting SSH2_MSG_NEWKEYS 
debug1: SSH2_MSG_NEWKEYS received 
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 RSA public key: /home/phablet/.ssh/id_rsa 
debug1: Server accepts key: pkalg ssh-rsa blen 535 
Agent admitted failure to sign using the key. 
debug1: Offering RSA public key: admin462@vps307796 
debug1: Server accepts key: pkalg ssh-rsa blen 535 
Agent admitted failure to sign using the key. 
debug1: Trying private key: /home/phablet/.ssh/id_dsa 
debug1: Trying private key: /home/phablet/.ssh/id_ecdsa 
debug1: Trying private key: /home/phablet/.ssh/id_ed25519 
debug1: No more authentication methods to try. 
Permission denied (publickey). 
  • If you have any key caching agent running (ssh-agent or another), you might test disabling with SSH_AUTH_SOCK= ssh -p 4029 admin@vps307796.ovh.net (Note that there is a space between "=" and "ssh") – user4556274 Dec 10 '16 at 0:04
  • @user4556274 Thank you for your reply. It works. – Mathieu Dec 10 '16 at 16:55

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