Проблема с настройкой аутентификации через публичный ключ

[Nik$]

Доброго времени суток.

Имеется сервер с Ubuntu версии 14.04 LTS. Устанавливал только связку Apach+Mysql+Php.

Необходимо настроить копирование файлов на бэкап-сервер.

Настройку проводил по инструкции с сайта своего хостера http://wiki.hetzner.de/index.php/Backup_Space_SSH_Keys/ru

Команды, вводимые мной и результаты их выполнения:

server@user:~$ ssh-keygen

(Нажмите, чтобы показать/скрыть)

Generating public/private rsa key pair.
Enter file in which to save the key (/home/server/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/server/.ssh/id_rsa.
Your public key has been saved in /home/server/.ssh/id_rsa.pub.
The key fingerprint is:
bc:03:1d:5b:13:a3:bb:d1:bb:64:26:72:d5:6c:65:2e server@user
The key's randomart image is:
+--[ RSA 2048]----+
|          o      |
|         . o     |
|        o o   o  |
|       o * + +   |
|      . S o E .  |
|       . = o .   |
|      . * =      |
|       o * .     |
|          .      |
+-----------------+

server@user:~$ cat .ssh/id_rsa.pub >> .ssh/backup_authorized_keys
server@user:~$ echo mkdir .ssh | sftp backup_user@backup_user.host.com

(Нажмите, чтобы показать/скрыть)

The authenticity of host 'backup_user.host.com (ip_backup_server)' can't be established.
RSA key fingerprint is 3d:7b:6f:99:5f:68:53:21:73:15:f9:2e:6b:3a:9f:e3.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'backup_user.host.com,ip_backup_server' (RSA) to the list of known hosts.
Enter passphrase for key '/home/server/.ssh/id_rsa':
backup_user@backup_user.host.com's password:
Connected to backup_user.host.com.
sftp> mkdir .ssh

server@user:~$

(Нажмите, чтобы показать/скрыть)

scp .ssh/backup_authorized_keys backup_user@backup_user.host.com:.ssh/authorized_keys
Enter passphrase for key '/home/server/.ssh/id_rsa':
backup_user@backup_user.host.com's password:
backup_authorized_keys                        100%  419     0.4KB/s   00:00

server@user:~$ sftp -vvv  backup_user@backup_user.host.com

(Нажмите, чтобы показать/скрыть)

OpenSSH_6.6.1, OpenSSL 1.0.1f 6 Jan 2014
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug2: ssh_connect: needpriv 0
debug1: Connecting to backup_user.host.com [ip_backup_server] port 22.
debug1: Connection established.
debug3: Incorrect RSA1 identifier
debug3: Could not load "/home/server/.ssh/id_rsa" as a RSA1 public key
debug1: identity file /home/server/.ssh/id_rsa type 1
debug1: identity file /home/server/.ssh/id_rsa-cert type -1
debug1: identity file /home/server/.ssh/id_dsa type -1
debug1: identity file /home/server/.ssh/id_dsa-cert type -1
debug1: identity file /home/server/.ssh/id_ecdsa type -1
debug1: identity file /home/server/.ssh/id_ecdsa-cert type -1
debug1: identity file /home/server/.ssh/id_ed25519 type -1
debug1: identity file /home/server/.ssh/id_ed25519-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_6.6.1p1 Ubuntu-2ubuntu2.3
debug1: Remote protocol version 2.0, remote software version mod_sftp/0.9.9
debug1: no match: mod_sftp/0.9.9
debug2: fd 3 setting O_NONBLOCK
debug3: load_hostkeys: loading entries for host "backup_user.host.com" from file "/home/server/.ssh/known_hosts"
debug3: load_hostkeys: found key type RSA in file /home/server/.ssh/known_hosts:1
debug3: load_hostkeys: loaded 1 keys
debug3: order_hostkeyalgs: prefer hostkeyalgs: ssh-rsa-cert-v01@openssh.com,ssh-rsa-cert-v00@openssh.com,ssh-rsa
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug2: kex_parse_kexinit: curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-rsa-cert-v01@openssh.com,ssh-rsa-cert-v00@openssh.com,ssh-rsa,ecdsa-sha2-nistp256-cert-v01@openssh.com,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp521-cert-v01@openssh.com,ssh-ed25519-cert-v01@openssh.com,ssh-dss-cert-v01@openssh.com,ssh-dss-cert-v00@openssh.com,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-ed25519,ssh-dss
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-gcm@openssh.com,aes256-gcm@openssh.com,chacha20-poly1305@openssh.com,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-gcm@openssh.com,aes256-gcm@openssh.com,chacha20-poly1305@openssh.com,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: hmac-md5-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-ripemd160-etm@openssh.com,hmac-sha1-96-etm@openssh.com,hmac-md5-96-etm@openssh.com,hmac-md5,hmac-sha1,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-ripemd160-etm@openssh.com,hmac-sha1-96-etm@openssh.com,hmac-md5-96-etm@openssh.com,hmac-md5,hmac-sha1,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,zlib@openssh.com,zlib
debug2: kex_parse_kexinit: none,zlib@openssh.com,zlib
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: kex_parse_kexinit: ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1,rsa1024-sha1
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss
debug2: kex_parse_kexinit: aes256-ctr,aes192-ctr,aes128-ctr,aes256-cbc,aes192-cbc,aes128-cbc,blowfish-ctr,blowfish-cbc,cast128-cbc,arcfour256,arcfour128,3des-ctr,3des-cbc
debug2: kex_parse_kexinit: aes256-ctr,aes192-ctr,aes128-ctr,aes256-cbc,aes192-cbc,aes128-cbc,blowfish-ctr,blowfish-cbc,cast128-cbc,arcfour256,arcfour128,3des-ctr,3des-cbc
debug2: kex_parse_kexinit: hmac-sha2-256,hmac-sha2-512,hmac-sha1,hmac-sha1-96,hmac-md5,hmac-md5-96,hmac-ripemd160,umac-64@openssh.com
debug2: kex_parse_kexinit: hmac-sha2-256,hmac-sha2-512,hmac-sha1,hmac-sha1-96,hmac-md5,hmac-md5-96,hmac-ripemd160,umac-64@openssh.com
debug2: kex_parse_kexinit: none
debug2: kex_parse_kexinit: none
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: mac_setup: setup hmac-md5
debug1: kex: server->client aes128-ctr hmac-md5 none
debug2: mac_setup: setup hmac-md5
debug1: kex: client->server aes128-ctr hmac-md5 none
debug1: sending SSH2_MSG_KEX_ECDH_INIT
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: RSA 3d:7b:6f:99:5f:68:53:21:73:15:f9:2e:6b:3a:9f:e3
debug3: load_hostkeys: loading entries for host "backup_user.host.com" from file "/home/server/.ssh/known_hosts"
debug3: load_hostkeys: found key type RSA in file /home/server/.ssh/known_hosts:1
debug3: load_hostkeys: loaded 1 keys
debug3: load_hostkeys: loading entries for host "ip_backup_server" from file "/home/server/.ssh/known_hosts"
debug3: load_hostkeys: found key type RSA in file /home/server/.ssh/known_hosts:1
debug3: load_hostkeys: loaded 1 keys
debug1: Host 'backup_user.host.com' is known and matches the RSA host key.
debug1: Found key in /home/server/.ssh/known_hosts:1
debug1: ssh_rsa_verify: signature correct
debug2: kex_derive_keys
debug2: set_newkeys: mode 1
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug2: set_newkeys: mode 0
debug1: SSH2_MSG_NEWKEYS received
debug1: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug2: key: /home/server/.ssh/id_rsa (0x7f35cdb066d0),
debug2: key: /home/server/.ssh/id_dsa ((nil)),
debug2: key: /home/server/.ssh/id_ecdsa ((nil)),
debug2: key: /home/server/.ssh/id_ed25519 ((nil)),
debug1: Authentications that can continue: publickey,password
debug3: start over, passed a different list publickey,password
debug3: preferred gssapi-keyex,gssapi-with-mic,publickey,keyboard-interactive,password
debug3: authmethod_lookup publickey
debug3: remaining preferred: keyboard-interactive,password
debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey
debug1: Offering RSA public key: /home/server/.ssh/id_rsa
debug3: send_pubkey_test
debug2: we sent a publickey packet, wait for reply
debug1: Server accepts key: pkalg ssh-rsa blen 279
debug2: input_userauth_pk_ok: fp bc:03:1d:5b:13:a3:bb:d1:bb:64:26:72:d5:6c:65:2e
debug3: sign_and_send_pubkey: RSA bc:03:1d:5b:13:a3:bb:d1:bb:64:26:72:d5:6c:65:2e
debug1: key_parse_private2: missing begin marker
debug1: key_parse_private_pem: PEM_read_PrivateKey failed
debug1: read PEM private key done: type <unknown>
Enter passphrase for key '/home/server/.ssh/id_rsa':

Как видно, команды выполнял из инструкции, однако все равно запрашивается ключевая фраза ключа. Подозреваю, что ошибка связана со следующими строчками:
debug1: key_parse_private2: missing begin marker
debug1: key_parse_private_pem: PEM_read_PrivateKey failed
debug1: read PEM private key done: type <unknown>

Перерыл массу страниц в интернете, большинство советов сводится к тому, что у папки .ssh, ключа id_rsa неверные разрешения. Папке поставил 700, ключу 600. Проблема не устранилась.

Помогите, пожалуйста, решить дать направление в решении данной проблемы.

Nik$,
Просьба - ознакомиться с Правилами. Листинги подправил.

Правила форума
1. Основные положения
1.4. Листинги и содержимое текстовых файлов следует добавлять в сообщение с помощью тега [spоiler]...[/spоiler], либо прикреплять к сообщению в виде отдельного файла.

-- it0r

[spk-ubuntu]

Проблема в чём? В том, что запрашивает пароль к ключу? Если в этом, то лечится повторной генерацией ключа с пустой парольной фразой.