SSH ne lit apparemment pas les clés dans ~/.ssh

Ceci est la sortie d'un client Ubuntu 16.04 :

OpenSSH_7.2p2 Ubuntu-4, OpenSSL 1.0.2g-fips  1 Mar 2016
debug1: Reading configuration data /home/manuth/.ssh/config
debug1: /home/manuth/.ssh/config line 1: Applying options for r2d2.manuth.life
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug1: Connecting to r2d2.manuth.life [103.12.163.90] port 900.
debug1: Connection established.
debug1: identity file /home/manuth/.ssh/dqar-rsa type 1
debug1: key_load_public: No such file or directory
debug1: identity file /home/manuth/.ssh/dqar-rsa-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_7.2p2 Ubuntu-4
ssh_exchange_identification: Connection closed by remote host

Le chemin d'accès et l'autorisation pour /home/manuth/.ssh/dqar-rsa sont également corrects :

$ ls -l /home/manuth/.ssh/dqar-rsa*
-rw------- 1 manuth manuth 3243 Nov  7 11:27 /home/manuth/.ssh/dqar-rsa
-rw-r--r-- 1 manuth manuth  740 Nov  7 11:27 /home/manuth/.ssh/dqar-rsa.pub

L'entrée pour cet hôte dans ~/.ssh/config est :

host r2d2.manuth.life
 IdentityFile ~/.ssh/dqar-rsa
 Port 900
 IdentitiesOnly yes
 ForwardX11 yes

Si j'essaie de commenter le IdentityFile il ne lit même pas les lignes id_* à l'intérieur ~/.ssh :

OpenSSH_7.2p2 Ubuntu-4, OpenSSL 1.0.2g-fips  1 Mar 2016
debug1: Reading configuration data /home/manuth/.ssh/config
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug1: Connecting to r2d2.manuth.life [103.12.163.90] port 900.
debug1: Connection established.
debug1: identity file /home/manuth/.ssh/id_rsa type 1
debug1: key_load_public: No such file or directory
debug1: identity file /home/manuth/.ssh/id_rsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/manuth/.ssh/id_dsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/manuth/.ssh/id_dsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/manuth/.ssh/id_ecdsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/manuth/.ssh/id_ecdsa-cert type -1
debug1: identity file /home/manuth/.ssh/id_ed25519 type 4
debug1: key_load_public: No such file or directory
debug1: identity file /home/manuth/.ssh/id_ed25519-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_7.2p2 Ubuntu-4
ssh_exchange_identification: Connection closed by remote host

Il semble que cette question soit apparue soudainement aujourd'hui.

Edit : contenu à l'intérieur ~/.ssh :

$ ls -la
insgesamt 36
drwx------  2 manuth manuth 4096 Nov  7 16:28 .
drwxr-xr-x 53 manuth manuth 4096 Nov  7 13:31 ..
-rw-r--r--  1 manuth manuth  805 Nov  7 12:10 authorized_keys
-rw-r--r--  1 manuth manuth  543 Nov  7 13:47 config
-rw-------  1 manuth manuth  411 Nov  7 12:10 dqar-ed25519
-rw-r--r--  1 manuth manuth   96 Nov  7 12:10 dqar-ed25519.pub
-rw-------  1 manuth manuth 3243 Nov  7 12:10 dqar-rsa
-rw-r--r--  1 manuth manuth  740 Nov  7 12:10 dqar-rsa.pub
-rw-r--r--  1 manuth manuth 1990 Nov  7 15:14 known_hosts

Edit 2 : Ah hah, la sortie de la console était plusieurs lignes de ceci :

Nov 7 13:51:32 dqar sshd [11316]: fatal: Missing privilege separation directory: /var/empty

Le serveur en question est FreeBSD 10.3.