为什么我需要输入密码？只有一用户？不是其他的吗？密钥没有验证 ssh 连接吗？
Authentication succeeded (keyboard-interactive).
来自本地主机的完整日志：
thufir@doge:~$
thufir@doge:~$ ssh [email protected] -vvvvv
OpenSSH_7.2p2 Ubuntu-4ubuntu1, OpenSSL 1.0.2g 1 Mar 2016
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug2: resolving "fqdn.example.com" port 22
debug2: ssh_connect_direct: needpriv 0
debug1: Connecting to fqdn.example.com [xxx.xxx.xxx.xxx] port 22.
debug1: Connection established.
debug1: identity file /home/thufir/.ssh/id_rsa type 1
debug1: key_load_public: No such file or directory
debug1: identity file /home/thufir/.ssh/id_rsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/thufir/.ssh/id_dsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/thufir/.ssh/id_dsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/thufir/.ssh/id_ecdsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/thufir/.ssh/id_ecdsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/thufir/.ssh/id_ed25519 type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/thufir/.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-4ubuntu1
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
debug2: fd 3 setting O_NONBLOCK
debug1: Authenticating to fqdn.example.com:22 as 'thufir'
debug3: hostkeys_foreach: reading file "/home/thufir/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /home/thufir/.ssh/known_hosts:1
debug3: load_hostkeys: loaded 1 keys from fqdn.example.com
debug3: order_hostkeyalgs: prefer hostkeyalgs: [email protected],[email protected],[email protected],ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521
debug3: send packet: type 20
debug1: SSH2_MSG_KEXINIT sent
debug3: receive packet: type 20
debug1: SSH2_MSG_KEXINIT received
debug2: local client KEXINIT proposal
debug2: KEX algorithms: [email protected],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,ext-info-c
debug2: host key algorithms: [email protected],[email protected],[email protected],ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,[email protected],[email protected],ssh-ed25519,rsa-sha2-512,rsa-sha2-256,ssh-rsa
debug2: ciphers ctos: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected],aes128-cbc,aes192-cbc,aes256-cbc,3des-cbc
debug2: ciphers stoc: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected],aes128-cbc,aes192-cbc,aes256-cbc,3des-cbc
debug2: MACs ctos: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: MACs stoc: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: compression ctos: none,[email protected],zlib
debug2: compression stoc: none,[email protected],zlib
debug2: languages ctos:
debug2: languages stoc:
debug2: first_kex_follows 0
debug2: reserved 0
debug2: peer server KEXINIT proposal
debug2: KEX algorithms: [email protected],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha1
debug2: host key algorithms: ssh-rsa,rsa-sha2-512,rsa-sha2-256,ecdsa-sha2-nistp256,ssh-ed25519
debug2: ciphers ctos: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected]
debug2: ciphers stoc: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected]
debug2: MACs ctos: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: MACs stoc: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: compression ctos: none,[email protected]
debug2: compression stoc: none,[email protected]
debug2: languages ctos:
debug2: languages stoc:
debug2: first_kex_follows 0
debug2: reserved 0
debug1: kex: algorithm: [email protected]
debug1: kex: host key algorithm: ecdsa-sha2-nistp256
debug1: kex: server->client cipher: [email protected] MAC: <implicit> compression: none
debug1: kex: client->server cipher: [email protected] MAC: <implicit> compression: none
debug3: send packet: type 30
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug3: receive packet: type 31
debug1: Server host key: ecdsa-sha2-nistp256 SHA256:IdFVo/3ets3QiQ+cZoW9EYN1BYCTok8We6mqR8yiV0E
debug3: hostkeys_foreach: reading file "/home/thufir/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /home/thufir/.ssh/known_hosts:1
debug3: load_hostkeys: loaded 1 keys from fqdn.example.com
debug3: hostkeys_foreach: reading file "/home/thufir/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /home/thufir/.ssh/known_hosts:2
debug3: load_hostkeys: loaded 1 keys from xxx.xxx.xxx.xxx
debug1: Host 'fqdn.example.com' is known and matches the ECDSA host key.
debug1: Found key in /home/thufir/.ssh/known_hosts:1
debug3: send packet: type 21
debug2: set_newkeys: mode 1
debug1: rekey after 134217728 blocks
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug3: receive packet: type 21
debug2: set_newkeys: mode 0
debug1: rekey after 134217728 blocks
debug1: SSH2_MSG_NEWKEYS received
debug2: key: /home/thufir/.ssh/id_rsa (0x5617a39bdaa0), agent
debug2: key: /home/thufir/.ssh/id_dsa ((nil))
debug2: key: /home/thufir/.ssh/id_ecdsa ((nil))
debug2: key: /home/thufir/.ssh/id_ed25519 ((nil))
debug3: send packet: type 5
debug3: receive packet: type 7
debug1: SSH2_MSG_EXT_INFO received
debug1: kex_input_ext_info: server-sig-algs=<rsa-sha2-256,rsa-sha2-512>
debug3: receive packet: type 6
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug3: send packet: type 50
debug3: receive packet: type 51
debug1: Authentications that can continue: publickey,keyboard-interactive
debug3: start over, passed a different list publickey,keyboard-interactive
debug3: preferred gssapi-keyex,gssapi-with-mic,publickey,keyboard-interactive
debug3: authmethod_lookup publickey
debug3: remaining preferred: keyboard-interactive
debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey
debug1: Offering RSA public key: /home/thufir/.ssh/id_rsa
debug3: send_pubkey_test
debug3: send packet: type 50
debug2: we sent a publickey packet, wait for reply
debug3: receive packet: type 51
debug1: Authentications that can continue: publickey,keyboard-interactive
debug1: Trying private key: /home/thufir/.ssh/id_dsa
debug3: no such identity: /home/thufir/.ssh/id_dsa: No such file or directory
debug1: Trying private key: /home/thufir/.ssh/id_ecdsa
debug3: no such identity: /home/thufir/.ssh/id_ecdsa: No such file or directory
debug1: Trying private key: /home/thufir/.ssh/id_ed25519
debug3: no such identity: /home/thufir/.ssh/id_ed25519: No such file or directory
debug2: we did not send a packet, disable method
debug3: authmethod_lookup keyboard-interactive
debug3: remaining preferred:
debug3: authmethod_is_enabled keyboard-interactive
debug1: Next authentication method: keyboard-interactive
debug2: userauth_kbdint
debug3: send packet: type 50
debug2: we sent a keyboard-interactive packet, wait for reply
debug3: receive packet: type 60
debug2: input_userauth_info_req
debug2: input_userauth_info_req: num_prompts 1
Password:
debug3: send packet: type 61
debug3: receive packet: type 60
debug2: input_userauth_info_req
debug2: input_userauth_info_req: num_prompts 0
debug3: send packet: type 61
debug3: receive packet: type 52
debug1: Authentication succeeded (keyboard-interactive).
Authenticated to fqdn.example.com ([xxx.xxx.xxx.xxx]:22).
debug1: channel 0: new [client-session]
debug3: ssh_session2_open: channel_new: 0
debug2: channel 0: send open
debug3: send packet: type 90
debug1: Requesting [email protected]
debug3: send packet: type 80
debug1: Entering interactive session.
debug1: pledge: network
debug3: receive packet: type 80
debug1: client_input_global_request: rtype [email protected] want_reply 0
debug3: receive packet: type 91
debug2: callback start
debug2: fd 3 setting TCP_NODELAY
debug3: ssh_packet_set_tos: set IP_TOS 0x10
debug2: client_session2_setup: id 0
debug2: channel 0: request pty-req confirm 1
debug3: send packet: type 98
debug1: Sending environment.
debug3: Ignored env XDG_VTNR
debug3: Ignored env XDG_SESSION_ID
debug3: Ignored env CLUTTER_IM_MODULE
debug3: Ignored env XDG_GREETER_DATA_DIR
debug3: Ignored env SESSION
debug3: Ignored env GPG_AGENT_INFO
debug3: Ignored env SHELL
debug3: Ignored env TERM
debug3: Ignored env VTE_VERSION
debug3: Ignored env QT_LINUX_ACCESSIBILITY_ALWAYS_ON
debug3: Ignored env WINDOWID
debug3: Ignored env OLDPWD
debug3: Ignored env UPSTART_SESSION
debug3: Ignored env GNOME_KEYRING_CONTROL
debug3: Ignored env GTK_MODULES
debug3: Ignored env USER
debug3: Ignored env LS_COLORS
debug3: Ignored env QT_ACCESSIBILITY
debug3: Ignored env XDG_SESSION_PATH
debug3: Ignored env XDG_SEAT_PATH
debug3: Ignored env SSH_AUTH_SOCK
debug3: Ignored env DEFAULTS_PATH
debug3: Ignored env XDG_CONFIG_DIRS
debug3: Ignored env PATH
debug3: Ignored env DESKTOP_SESSION
debug3: Ignored env QT_IM_MODULE
debug3: Ignored env QT_QPA_PLATFORMTHEME
debug3: Ignored env XDG_SESSION_TYPE
debug3: Ignored env PWD
debug3: Ignored env JOB
debug3: Ignored env XMODIFIERS
debug3: Ignored env GNOME_KEYRING_PID
debug1: Sending env LANG = en_CA.UTF-8
debug2: channel 0: request env confirm 0
debug3: send packet: type 98
debug3: Ignored env GDM_LANG
debug3: Ignored env MANDATORY_PATH
debug3: Ignored env IM_CONFIG_PHASE
debug3: Ignored env COMPIZ_CONFIG_PROFILE
debug3: Ignored env GDMSESSION
debug3: Ignored env SESSIONTYPE
debug3: Ignored env GTK2_MODULES
debug3: Ignored env HOME
debug3: Ignored env XDG_SEAT
debug3: Ignored env SHLVL
debug3: Ignored env LANGUAGE
debug3: Ignored env GNOME_DESKTOP_SESSION_ID
debug3: Ignored env UPSTART_INSTANCE
debug3: Ignored env UPSTART_EVENTS
debug3: Ignored env XDG_SESSION_DESKTOP
debug3: Ignored env LOGNAME
debug3: Ignored env COMPIZ_BIN_PATH
debug3: Ignored env QT4_IM_MODULE
debug3: Ignored env XDG_DATA_DIRS
debug3: Ignored env DBUS_SESSION_BUS_ADDRESS
debug3: Ignored env LESSOPEN
debug3: Ignored env INSTANCE
debug3: Ignored env UPSTART_JOB
debug3: Ignored env XDG_RUNTIME_DIR
debug3: Ignored env DISPLAY
debug3: Ignored env XDG_CURRENT_DESKTOP
debug3: Ignored env GTK_IM_MODULE
debug3: Ignored env LESSCLOSE
debug3: Ignored env XAUTHORITY
debug3: Ignored env _
debug2: channel 0: request shell confirm 1
debug3: send packet: type 98
debug2: callback done
debug2: channel 0: open confirm rwindow 0 rmax 32768
debug3: receive packet: type 99
debug2: channel_input_status_confirm: type 99 id 0
debug2: PTY allocation request accepted on channel 0
debug2: channel 0: rcvd adjust 2097152
debug3: receive packet: type 99
debug2: channel_input_status_confirm: type 99 id 0
debug2: shell request accepted on channel 0
Welcome to Ubuntu 16.04.1 LTS (GNU/Linux 4.4.0-53-generic x86_64)
* Documentation: https://help.ubuntu.com
* Management: https://landscape.canonical.com
* Support: https://ubuntu.com/advantage
Get cloud support with Ubuntu Advantage Cloud Guest:
http://www.ubuntu.com/business/services/cloud
0 packages can be updated.
0 updates are security updates.
Last login: Mon Jan 9 19:31:03 2017 from yyy.yyy.yyy.yyy
thufir@ip-xxx-xxx-xxx-xxx:~$
thufir@ip-xxx-xxx-xxx-xxx:~$
thufir@ip-xxx-xxx-xxx-xxx:~$ exit
logout
debug3: receive packet: type 98
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug3: receive packet: type 98
debug1: client_input_channel_req: channel 0 rtype [email protected] reply 0
debug2: channel 0: rcvd eow
debug2: channel 0: close_read
debug2: channel 0: input open -> closed
debug3: receive packet: type 96
debug2: channel 0: rcvd eof
debug2: channel 0: output open -> drain
debug2: channel 0: obuf empty
debug2: channel 0: close_write
debug2: channel 0: output drain -> closed
debug3: receive packet: type 97
debug2: channel 0: rcvd close
debug3: channel 0: will not send data after close
debug2: channel 0: almost dead
debug2: channel 0: gc: notify user
debug2: channel 0: gc: user detached
debug2: channel 0: send close
debug3: send packet: type 97
debug2: channel 0: is dead
debug2: channel 0: garbage collecting
debug1: channel 0: free: client-session, nchannels 1
debug3: channel 0: status: The following connections are open:
#0 client-session (t4 r0 i3/0 o3/0 fd -1/-1 cc -1)
debug3: send packet: type 1
Connection to fqdn.example.com closed.
Transferred: sent 2992, received 4028 bytes, in 4.6 seconds
Bytes per second: sent 644.6, received 867.8
debug1: Exit status 0
thufir@doge:~$
远程 ssh 配置：
ubuntu@ip-xxx-xx-x-xx:~$ cat /etc/ssh/sshd_config
# Package generated configuration file
# See the sshd_config(5) manpage for details
# What ports, IPs and protocols we listen for
Port 22
# Use these options to restrict which interfaces/protocols sshd will bind to
#ListenAddress ::
#ListenAddress 0.0.0.0
Protocol 2
# HostKeys for protocol version 2
HostKey /etc/ssh/ssh_host_rsa_key
HostKey /etc/ssh/ssh_host_dsa_key
HostKey /etc/ssh/ssh_host_ecdsa_key
HostKey /etc/ssh/ssh_host_ed25519_key
#Privilege Separation is turned on for security
UsePrivilegeSeparation yes
# Lifetime and size of ephemeral version 1 server key
KeyRegenerationInterval 3600
ServerKeyBits 1024
# Logging
SyslogFacility AUTH
LogLevel INFO
# Authentication:
LoginGraceTime 120
#PermitRootLogin prohibit-password
PermitRootLogin no
StrictModes yes
RSAAuthentication yes
PubkeyAuthentication yes
#AuthorizedKeysFile %h/.ssh/authorized_keys
# Don't read the user's ~/.rhosts and ~/.shosts files
IgnoreRhosts yes
# For this to work you will also need host keys in /etc/ssh_known_hosts
RhostsRSAAuthentication no
# similar for protocol version 2
HostbasedAuthentication no
# Uncomment if you don't trust ~/.ssh/known_hosts for RhostsRSAAuthentication
#IgnoreUserKnownHosts yes
# To enable empty passwords, change to yes (NOT RECOMMENDED)
PermitEmptyPasswords no
# Change to yes to enable challenge-response passwords (beware issues with
# some PAM modules and threads)
ChallengeResponseAuthentication yes
# Change to no to disable tunnelled clear text passwords
PasswordAuthentication no
# Kerberos options
#KerberosAuthentication no
#KerberosGetAFSToken no
#KerberosOrLocalPasswd yes
#KerberosTicketCleanup yes
# GSSAPI options
#GSSAPIAuthentication no
#GSSAPICleanupCredentials yes
X11Forwarding yes
X11DisplayOffset 10
PrintMotd no
PrintLastLog yes
TCPKeepAlive yes
#UseLogin no
#MaxStartups 10:30:60
#Banner /etc/issue.net
# Allow client to pass locale environment variables
AcceptEnv LANG LC_*
Subsystem sftp /usr/lib/openssh/sftp-server
# Set this to 'yes' to enable PAM authentication, account processing,
# and session processing. If this is enabled, PAM authentication will
# be allowed through the ChallengeResponseAuthentication and
# PasswordAuthentication. Depending on your PAM configuration,
# PAM authentication via ChallengeResponseAuthentication may bypass
# the setting of "PermitRootLogin without-password".
# If you just want the PAM account and session checks to run without
# PAM authentication, then enable this but set PasswordAuthentication
# and ChallengeResponseAuthentication to 'no'.
UsePAM yes
AllowUsers thufir ubuntu
DenyUsers root
ubuntu@ip-xxx-xx-x-xx:~$
但用户ubuntu可以 ssh没有提示输入密码。为什么？不，我还没有创建第三个用户来查看会发生什么（目前）。
这是在 AWS 实例上。ubuntu用户是默认的。
**非详细登录：
thufir@doge:~$
thufir@doge:~$ ssh [email protected]
Permission denied (publickey).
thufir@doge:~$
**
答案1
Fromm ssh-vvvssh 服务器正在使用键盘交互。
首先确保您可以使用密钥登录。
然后，编辑 sshd_config 并将以下内容设置为 no
PasswordAuthentication no
KbdInteractiveAuthentication no
ChallengeResponseAuthentication no
并重新启动 ssh 服务器。