我有一台带有OpenSSH的远程Ubuntu服务器，我们在学校的项目中使用它。 它使用生成的公用密钥和专用密钥进行设置，然后使用ssh_copy_id命令将公用密钥复制到服务器上。 在过去的几周中，我们可以通过私钥连接到服务器，而无需输入密码。现在，它开始再次要求输入密码。
我尝试将.ssh和authorized_keys的权限分别更改为700和600。
我在SSHD-config中添加了这两行：“ RSAAuthentication yes”，“ PubkeyAuthentication yes”
我已在此帖子中添加了SSH -vvv输出，完整的SSHD配置和auth.log。
SSH -vvv输出
[我将实际IP地址更改为[IP地址]，并将用户名更改为用户]
OpenSSH_7.9p1, OpenSSL 1.1.1a 20 Nov 2018
debug1: Reading configuration data /etc/ssh/ssh_config
debug2: resolve_canonicalize: hostname IP-ADDRESS is address
debug2: ssh_connect_direct
debug1: Connecting to IP-ADDRESS [IP-ADDRESS] port 22.
debug1: Connection established.
debug1: identity file /c/Users/Stefan/.ssh/id_rsa type 0
debug1: identity file /c/Users/Stefan/.ssh/id_rsa-cert type -1
debug1: identity file /c/Users/Stefan/.ssh/id_dsa type -1
debug1: identity file /c/Users/Stefan/.ssh/id_dsa-cert type -1
debug1: identity file /c/Users/Stefan/.ssh/id_ecdsa type -1
debug1: identity file /c/Users/Stefan/.ssh/id_ecdsa-cert type -1
debug1: identity file /c/Users/Stefan/.ssh/id_ed25519 type -1
debug1: identity file /c/Users/Stefan/.ssh/id_ed25519-cert type -1
debug1: identity file /c/Users/Stefan/.ssh/id_xmss type -1
debug1: identity file /c/Users/Stefan/.ssh/id_xmss-cert type -1
debug1: Local version string SSH-2.0-OpenSSH_7.9
debug1: Remote protocol version 2.0, remote software version OpenSSH_7.6p1 Ubuntu-4ubuntu0.3
debug1: match: OpenSSH_7.6p1 Ubuntu-4ubuntu0.3 pat OpenSSH_7.0*,OpenSSH_7.1*,OpenSSH_7.2*,OpenSSH_7.3*,OpenSSH_7.4*,OpenSSH_7.5*,OpenSSH_7.6*,OpenSSH_7.7* compat 0x04000002
debug2: fd 4 setting O_NONBLOCK
debug1: Authenticating to IP-ADDRESS:22 as 'user'
debug3: hostkeys_foreach: reading file "/c/Users/Stefan/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /c/Users/Stefan/.ssh/known_hosts:1
debug3: load_hostkeys: loaded 1 keys from IP-ADDRESS
debug3: order_hostkeyalgs: prefer hostkeyalgs: ecdsa-sha2-nistp256-cert-v01@openssh.com,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp521-cert-v01@openssh.com,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: curve25519-sha256,curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,diffie-hellman-group14-sha256,diffie-hellman-group14-sha1,ext-info-c
debug2: host key algorithms: ecdsa-sha2-nistp256-cert-v01@openssh.com,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp521-cert-v01@openssh.com,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-ed25519-cert-v01@openssh.com,rsa-sha2-512-cert-v01@openssh.com,rsa-sha2-256-cert-v01@openssh.com,ssh-rsa-cert-v01@openssh.com,ssh-ed25519,rsa-sha2-512,rsa-sha2-256,ssh-rsa
debug2: ciphers ctos: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com,aes128-cbc,3des-cbc,aes256-cbc,aes192-cbc
debug2: ciphers stoc: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com,aes128-cbc,3des-cbc,aes256-cbc,aes192-cbc
debug2: MACs ctos: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: MACs stoc: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: compression ctos: none,zlib@openssh.com,zlib
debug2: compression stoc: none,zlib@openssh.com,zlib
debug2: languages ctos:
debug2: languages stoc:
debug2: first_kex_follows 0
debug2: reserved 0
debug2: peer server KEXINIT proposal
debug2: KEX algorithms: curve25519-sha256,curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,diffie-hellman-group14-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: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com
debug2: ciphers stoc: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com
debug2: MACs ctos: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: MACs stoc: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: compression ctos: none,zlib@openssh.com
debug2: compression stoc: none,zlib@openssh.com
debug2: languages ctos:
debug2: languages stoc:
debug2: first_kex_follows 0
debug2: reserved 0
debug1: kex: algorithm: curve25519-sha256
debug1: kex: host key algorithm: ecdsa-sha2-nistp256
debug1: kex: server->client cipher: chacha20-poly1305@openssh.com MAC: <implicit> compression: none
debug1: kex: client->server cipher: chacha20-poly1305@openssh.com 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:zZbR3+9/6C/D5Acw9pFKpkhOdoSngiJ7WY8pK6Bz0hA
debug3: hostkeys_foreach: reading file "/c/Users/Stefan/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /c/Users/Stefan/.ssh/known_hosts:1
debug3: load_hostkeys: loaded 1 keys from IP-ADDRESS
debug1: Host 'IP-ADDRESS' is known and matches the ECDSA host key.
debug1: Found key in /c/Users/Stefan/.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
debug1: SSH2_MSG_NEWKEYS received
debug2: set_newkeys: mode 0
debug1: rekey after 134217728 blocks
debug1: Will attempt key: /c/Users/Stefan/.ssh/id_rsa RSA SHA256:1Gfcg7nk7FNsCRE/TnZt4uKvnWjJRSV0CjgCFDH5/po
debug1: Will attempt key: /c/Users/Stefan/.ssh/id_dsa
debug1: Will attempt key: /c/Users/Stefan/.ssh/id_ecdsa
debug1: Will attempt key: /c/Users/Stefan/.ssh/id_ed25519
debug1: Will attempt key: /c/Users/Stefan/.ssh/id_xmss
debug2: pubkey_prepare: done
debug3: send packet: type 5
debug3: receive packet: type 7
debug1: SSH2_MSG_EXT_INFO received
debug1: kex_input_ext_info: server-sig-algs=<ssh-ed25519,ssh-rsa,rsa-sha2-256,rsa-sha2-512,ssh-dss,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521>
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: password
debug3: start over, passed a different list password
debug3: preferred publickey,keyboard-interactive,password
debug3: authmethod_lookup password
debug3: remaining preferred: ,keyboard-interactive,password
debug3: authmethod_is_enabled password
debug1: Next authentication method: password
user@IP-ADDRESS's password:
SSHD配置
# $OpenBSD: sshd_config,v 1.101 2017/03/14 07:19:07 djm Exp $
# This is the sshd server system-wide configuration file. See
# sshd_config(5) for more information.
# This sshd was compiled with PATH=/usr/bin:/bin:/usr/sbin:/sbin
# The strategy used for options in the default sshd_config shipped with
# OpenSSH is to specify options with their default value where
# possible, but leave them commented. Uncommented options override the
# default value.
#Port 22
#AddressFamily any
#ListenAddress 0.0.0.0
#ListenAddress ::
#HostKey /etc/ssh/ssh_host_rsa_key
#HostKey /etc/ssh/ssh_host_ecdsa_key
#HostKey /etc/ssh/ssh_host_ed25519_key
#Ciphers and keying
#RekeyLimit default none
# Logging
#SyslogFacility AUTH
#LogLevel INFO
# Authentication:
#LoginGraceTime 2m
#PermitRootLogin prohibit-password
#StrictModes yes
#MaxAuthTries 6
#MaxSessions 10
RSAAuthentication yes
PubkeyAuthentication yes
# Expect .ssh/authorized_keys2 to be disregarded by default in future.
#AuthorizedKeysFile .ssh/authorized_keys .ssh/authorized_keys2
#AuthorizedPrincipalsFile none
#AuthorizedKeysCommand none
#AuthorizedKeysCommandUser nobody
# For this to work you will also need host keys in /etc/ssh/ssh_known_hosts
#HostbasedAuthentication no
# Change to yes if you don't trust ~/.ssh/known_hosts for
# HostbasedAuthentication
#IgnoreUserKnownHosts no
# Don't read the user's ~/.rhosts and ~/.shosts files
#IgnoreRhosts yes
# To disable tunneled clear text passwords, change to no here!
#PasswordAuthentication yes
#PermitEmptyPasswords no
# Change to yes to enable challenge-response passwords (beware issues with
# some PAM modules and threads)
ChallengeResponseAuthentication no
# Kerberos options
#KerberosAuthentication no
#KerberosOrLocalPasswd yes
#KerberosTicketCleanup yes
#KerberosGetAFSToken no
# GSSAPI options
#GSSAPIAuthentication no
#GSSAPICleanupCredentials yes
#GSSAPIStrictAcceptorCheck yes
#GSSAPIKeyExchange no
# 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
#AllowAgentForwarding yes
#AllowTcpForwarding yes
#GatewayPorts no
X11Forwarding yes
#X11DisplayOffset 10
#X11UseLocalhost yes
#PermitTTY yes
PrintMotd no
#PrintLastLog yes
#TCPKeepAlive yes
#UseLogin no
#PermitUserEnvironment no
#Compression delayed
#ClientAliveInterval 0
#ClientAliveCountMax 3
#UseDNS no
#PidFile /var/run/sshd.pid
#MaxStartups 10:30:100
#PermitTunnel no
#ChrootDirectory none
#VersionAddendum none
# no default banner path
#Banner none
# Allow client to pass locale environment variables
AcceptEnv LANG LC_*
# override default of no subsystems
Subsystem sftp /usr/lib/openssh/sftp-server
# Example of overriding settings on a per-user basis
#Match User anoncvs
# X11Forwarding no
# AllowTcpForwarding no
# PermitTTY no
# ForceCommand cvs server
auth.log
将我的IP地址更改为[MY-IPADDRESS]，并将用户名更改为USER
Dec 26 09:41:49 linux sudo: pam_unix(sudo:session): session closed for user root
Dec 26 09:41:50 linux sshd[8991]: Received disconnect from [MY IP-ADDRESS] port 60301:11: disconnected by user
Dec 26 09:41:50 linux sshd[8991]: Disconnected from user USER [MY IP-ADDRESS] port 60301
Dec 26 09:41:50 linux sshd[8914]: pam_unix(sshd:session): session closed for user USER
Dec 26 09:41:50 linux systemd-logind[923]: Removed session 78.
Dec 26 09:41:55 linux sshd[9010]: Accepted password for student from [MY IP-ADDRESS] port 60318 ssh2
Dec 26 09:41:55 linux sshd[9010]: pam_unix(sshd:session): session opened for user USER by (uid=0)
Dec 26 09:41:56 linux systemd: pam_unix(systemd-user:session): session opened for user USER by (uid=0)
Dec 26 09:41:56 linux systemd-logind[923]: New session 80 of user student.
Dec 26 09:42:01 linux sudo: student : TTY=pts/0 ; PWD=/home/USER ; USER=root ; COMMAND=/usr/bin/less /var/log/auth.log
Dec 26 09:42:01 linux sudo: pam_unix(sudo:session): session opened for user root by USER(uid=0)