bb(14.07) 升级到 cc(15.05) 后，ssh 登录时，连接总被关闭： Connection to A.B.C.D closed

[moontide]

路由器是 极路由2

• cc(15.05) 的版本我从 2015-11-25 的版本一直升级到最新的 2015-12-13 版，都不行。
• 升级时，都是按照默认选项（保留配置）升级的。
• 不论用 root 密码登录，还是用 public key 登录，连接都会被关闭

但另外一台 TP-Link 路由器 (CPU 架构 = ar71xx) 从 OpenWRT 官方的 bb 版本升级到 cc 版本后，ssh 正常。

用密码登录时的 ssh 日志

OpenSSH_7.1p1, OpenSSL 1.0.2e-fips 3 Dec 2015
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 56: Applying options for *
debug2: ssh_connect: needpriv 0
debug1: Connecting to A.B.C.D [A.B.C.D] port 22.
debug1: Connection established.
debug1: identity file /home/LINUX的HOME目录/.ssh/id_rsa type 1
debug1: key_load_public: No such file or directory
debug1: identity file /home/LINUX的HOME目录/.ssh/id_rsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/LINUX的HOME目录/.ssh/id_dsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/LINUX的HOME目录/.ssh/id_dsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/LINUX的HOME目录/.ssh/id_ecdsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/LINUX的HOME目录/.ssh/id_ecdsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/LINUX的HOME目录/.ssh/id_ed25519 type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/LINUX的HOME目录/.ssh/id_ed25519-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_7.1
debug1: Remote protocol version 2.0, remote software version dropbear_2015.67
debug1: no match: dropbear_2015.67
debug2: fd 3 setting O_NONBLOCK
debug1: Authenticating to A.B.C.D:22 as 'root'
debug3: hostkeys_foreach: reading file "/home/LINUX的HOME目录/.ssh/known_hosts"
debug3: record_hostkey: found key type RSA in file /home/LINUX的HOME目录/.ssh/known_hosts:55
debug3: load_hostkeys: loaded 1 keys from A.B.C.D
debug3: order_hostkeyalgs: prefer hostkeyalgs: ssh-rsa-cert-v01@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
debug2: kex_parse_kexinit: ssh-rsa-cert-v01@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,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-ed25519
debug2: kex_parse_kexinit: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: 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,hmac-md5-etm@openssh.com,hmac-ripemd160-etm@openssh.com,hmac-sha1-96-etm@openssh.com,hmac-md5-96-etm@openssh.com,hmac-md5,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: 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,hmac-md5-etm@openssh.com,hmac-ripemd160-etm@openssh.com,hmac-sha1-96-etm@openssh.com,hmac-md5-96-etm@openssh.com,hmac-md5,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: diffie-hellman-group14-sha1,diffie-hellman-group1-sha1,kexguess2@matt.ucc.asn.au
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss
debug2: kex_parse_kexinit: aes128-ctr,aes256-ctr,aes128-cbc,aes256-cbc,3des-ctr,3des-cbc
debug2: kex_parse_kexinit: aes128-ctr,aes256-ctr,aes128-cbc,aes256-cbc,3des-ctr,3des-cbc
debug2: kex_parse_kexinit: hmac-sha1,hmac-md5
debug2: kex_parse_kexinit: hmac-sha1,hmac-md5
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 
debug1: kex: server->client aes128-ctr hmac-sha1 none
debug1: kex: client->server aes128-ctr hmac-sha1 none
debug1: kex: diffie-hellman-group14-sha1 need=20 dh_need=20
debug1: kex: diffie-hellman-group14-sha1 need=20 dh_need=20
debug1: sending SSH2_MSG_KEXDH_INIT
debug2: bits set: 1051/2048
debug1: expecting SSH2_MSG_KEXDH_REPLY
debug1: Server host key: ssh-rsa SHA256:9Exkk+G1ugx6C9xzgSUd/iMFxhYu11aw90zet4yoHVg
debug3: hostkeys_foreach: reading file "/home/LINUX的HOME目录/.ssh/known_hosts"
debug3: record_hostkey: found key type RSA in file /home/LINUX的HOME目录/.ssh/known_hosts:55
debug3: load_hostkeys: loaded 1 keys from A.B.C.D
debug1: Host 'A.B.C.D' is known and matches the RSA host key.
debug1: Found key in /home/LINUX的HOME目录/.ssh/known_hosts:55
debug2: bits set: 1044/2048
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/LINUX的HOME目录/.ssh/id_rsa (0x55e7b8dc6bf0),
debug2: key: /home/LINUX的HOME目录/.ssh/id_dsa ((nil)),
debug2: key: /home/LINUX的HOME目录/.ssh/id_ecdsa ((nil)),
debug2: key: /home/LINUX的HOME目录/.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/LINUX的HOME目录/.ssh/id_rsa
debug3: send_pubkey_test
debug2: we sent a publickey packet, wait for reply
debug1: Authentications that can continue: publickey,password
debug1: Trying private key: /home/LINUX的HOME目录/.ssh/id_dsa
debug3: no such identity: /home/LINUX的HOME目录/.ssh/id_dsa: No such file or directory
debug1: Trying private key: /home/LINUX的HOME目录/.ssh/id_ecdsa
debug3: no such identity: /home/LINUX的HOME目录/.ssh/id_ecdsa: No such file or directory
debug1: Trying private key: /home/LINUX的HOME目录/.ssh/id_ed25519
debug3: no such identity: /home/LINUX的HOME目录/.ssh/id_ed25519: No such file or directory
debug2: we did not send a packet, disable method
debug3: authmethod_lookup password
debug3: remaining preferred: ,password
debug3: authmethod_is_enabled password
debug1: Next authentication method: password
root@A.B.C.D's password: 
debug2: we sent a password packet, wait for reply
debug1: Authentications that can continue: publickey,password
Permission denied, please try again.                             <--------- 故意输错密码
root@A.B.C.D's password: 
debug2: we sent a password packet, wait for reply
debug1: Authentication succeeded (password).
Authenticated to A.B.C.D ([A.B.C.D]:22).
debug1: channel 0: new [client-session]
debug3: ssh_session2_open: channel_new: 0
debug2: channel 0: send open
debug1: Entering interactive session.
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
debug1: Sending environment.
debug3: Ignored env XDG_VTNR
debug3: Ignored env MATE_DESKTOP_SESSION_ID
debug3: Ignored env GIT_DISCOVERY_ACROSS_FILESYSTEM
debug3: Ignored env SSH_AGENT_PID
debug3: Ignored env XDG_SESSION_ID
debug3: Ignored env HOSTNAME
debug3: Ignored env IMSETTINGS_INTEGRATE_DESKTOP
debug3: Ignored env TERM
debug3: Ignored env SHELL
debug3: Ignored env HISTSIZE
debug3: Ignored env WINDOWID
debug3: Ignored env GNOME_KEYRING_CONTROL
debug3: Ignored env QTDIR
debug3: Ignored env QTINC
debug3: Ignored env IMSETTINGS_MODULE
debug3: Ignored env QT_GRAPHICSSYSTEM_CHECKED
debug3: Ignored env USER
debug3: Ignored env SVN_EDITOR
debug3: Ignored env LS_COLORS
debug3: Ignored env LD_LIBRARY_PATH
debug3: Ignored env SSH_AUTH_SOCK
debug3: Ignored env _JAVA_OPTIONS
debug3: Ignored env SESSION_MANAGER
debug3: Ignored env PATH
debug3: Ignored env MAIL
debug3: Ignored env DESKTOP_SESSION
debug3: Ignored env QT_IM_MODULE
debug3: Ignored env PWD
debug1: Sending env XMODIFIERS = @im=fcitx
debug2: channel 0: request env confirm 0
debug1: Sending env LANG = zh_CN.UTF-8
debug2: channel 0: request env confirm 0
debug3: Ignored env KDEDIRS
debug3: Ignored env SSH_ASKPASS
debug3: Ignored env HISTCONTROL
debug3: Ignored env JAVA_FONTS
debug3: Ignored env HOME
debug3: Ignored env XDG_SEAT
debug3: Ignored env SHLVL
debug3: Ignored env GTK_OVERLAY_SCROLLING
debug3: Ignored env LOGNAME
debug3: Ignored env CVS_RSH
debug3: Ignored env QTLIB
debug3: Ignored env QT4_IM_MODULE
debug3: Ignored env DBUS_SESSION_BUS_ADDRESS
debug3: Ignored env LESSOPEN
debug3: Ignored env DISPLAY
debug3: Ignored env XDG_RUNTIME_DIR
debug3: Ignored env XDG_CURRENT_DESKTOP
debug3: Ignored env ORACLE_HOME
debug3: Ignored env GTK_IM_MODULE
debug3: Ignored env COLORTERM
debug3: Ignored env XAUTHORITY
debug3: Ignored env _
debug2: channel 0: request shell confirm 1
debug2: callback done
debug2: channel 0: open confirm rwindow 24576 rmax 32759
debug2: channel_input_status_confirm: type 99 id 0
debug2: PTY allocation request accepted on channel 0
debug2: channel_input_status_confirm: type 99 id 0
debug2: shell request accepted on channel 0
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
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd close
debug2: channel 0: close_read
debug2: channel 0: input open -> closed
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
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)

Connection to A.B.C.D closed.        <------- 连接被关闭
Transferred: sent 3400, received 1520 bytes, in 0.0 seconds
Bytes per second: sent 199636.5, received 89249.3
debug1: Exit status 1

用 public key 登录时的 ssh 日志

$ ssh -vvv root@A.B.C.D 
OpenSSH_7.1p1, OpenSSL 1.0.2e-fips 3 Dec 2015
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 56: Applying options for *
debug2: ssh_connect: needpriv 0
debug1: Connecting to A.B.C.D [A.B.C.D] port 22.
debug1: Connection established.
debug1: identity file /home/LINUX的HOME目录/.ssh/id_rsa type 1
debug1: key_load_public: No such file or directory
debug1: identity file /home/LINUX的HOME目录/.ssh/id_rsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/LINUX的HOME目录/.ssh/id_dsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/LINUX的HOME目录/.ssh/id_dsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/LINUX的HOME目录/.ssh/id_ecdsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/LINUX的HOME目录/.ssh/id_ecdsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/LINUX的HOME目录/.ssh/id_ed25519 type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/LINUX的HOME目录/.ssh/id_ed25519-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_7.1
debug1: Remote protocol version 2.0, remote software version dropbear_2015.67
debug1: no match: dropbear_2015.67
debug2: fd 3 setting O_NONBLOCK
debug1: Authenticating to A.B.C.D:22 as 'root'
debug3: hostkeys_foreach: reading file "/home/LINUX的HOME目录/.ssh/known_hosts"
debug3: record_hostkey: found key type RSA in file /home/LINUX的HOME目录/.ssh/known_hosts:55
debug3: load_hostkeys: loaded 1 keys from A.B.C.D
debug3: order_hostkeyalgs: prefer hostkeyalgs: ssh-rsa-cert-v01@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
debug2: kex_parse_kexinit: ssh-rsa-cert-v01@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,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-ed25519
debug2: kex_parse_kexinit: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: 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,hmac-md5-etm@openssh.com,hmac-ripemd160-etm@openssh.com,hmac-sha1-96-etm@openssh.com,hmac-md5-96-etm@openssh.com,hmac-md5,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: 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,hmac-md5-etm@openssh.com,hmac-ripemd160-etm@openssh.com,hmac-sha1-96-etm@openssh.com,hmac-md5-96-etm@openssh.com,hmac-md5,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: diffie-hellman-group14-sha1,diffie-hellman-group1-sha1,kexguess2@matt.ucc.asn.au
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss
debug2: kex_parse_kexinit: aes128-ctr,aes256-ctr,aes128-cbc,aes256-cbc,3des-ctr,3des-cbc
debug2: kex_parse_kexinit: aes128-ctr,aes256-ctr,aes128-cbc,aes256-cbc,3des-ctr,3des-cbc
debug2: kex_parse_kexinit: hmac-sha1,hmac-md5
debug2: kex_parse_kexinit: hmac-sha1,hmac-md5
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 
debug1: kex: server->client aes128-ctr hmac-sha1 none
debug1: kex: client->server aes128-ctr hmac-sha1 none
debug1: kex: diffie-hellman-group14-sha1 need=20 dh_need=20
debug1: kex: diffie-hellman-group14-sha1 need=20 dh_need=20
debug1: sending SSH2_MSG_KEXDH_INIT
debug2: bits set: 987/2048
debug1: expecting SSH2_MSG_KEXDH_REPLY
debug1: Server host key: ssh-rsa SHA256:9Exkk+G1ugx6C9xzgSUd/iMFxhYu11aw90zet4yoHVg
debug3: hostkeys_foreach: reading file "/home/LINUX的HOME目录/.ssh/known_hosts"
debug3: record_hostkey: found key type RSA in file /home/LINUX的HOME目录/.ssh/known_hosts:55
debug3: load_hostkeys: loaded 1 keys from A.B.C.D
debug1: Host 'A.B.C.D' is known and matches the RSA host key.
debug1: Found key in /home/LINUX的HOME目录/.ssh/known_hosts:55
debug2: bits set: 1008/2048
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/LINUX的HOME目录/.ssh/id_rsa (0x563e56c20bf0),
debug2: key: /home/LINUX的HOME目录/.ssh/id_dsa ((nil)),
debug2: key: /home/LINUX的HOME目录/.ssh/id_ecdsa ((nil)),
debug2: key: /home/LINUX的HOME目录/.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/LINUX的HOME目录/.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 SHA256:8OoX31yTo64JxMI8DB6w56PQqblrrI+gV95y/EmCv7I
debug3: sign_and_send_pubkey: RSA SHA256:8OoX31yTo64JxMI8DB6w56PQqblrrI+gV95y/EmCv7I
debug1: Authentication succeeded (publickey).       <-------- 公钥验证成功
Authenticated to A.B.C.D ([A.B.C.D]:22).
debug1: channel 0: new [client-session]
debug3: ssh_session2_open: channel_new: 0
debug2: channel 0: send open
debug1: Entering interactive session.
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
debug1: Sending environment.
debug3: Ignored env XDG_VTNR
debug3: Ignored env MATE_DESKTOP_SESSION_ID
debug3: Ignored env GIT_DISCOVERY_ACROSS_FILESYSTEM
debug3: Ignored env SSH_AGENT_PID
debug3: Ignored env XDG_SESSION_ID
debug3: Ignored env HOSTNAME
debug3: Ignored env IMSETTINGS_INTEGRATE_DESKTOP
debug3: Ignored env TERM
debug3: Ignored env SHELL
debug3: Ignored env HISTSIZE
debug3: Ignored env WINDOWID
debug3: Ignored env GNOME_KEYRING_CONTROL
debug3: Ignored env QTDIR
debug3: Ignored env QTINC
debug3: Ignored env IMSETTINGS_MODULE
debug3: Ignored env QT_GRAPHICSSYSTEM_CHECKED
debug3: Ignored env USER
debug3: Ignored env SVN_EDITOR
debug3: Ignored env LS_COLORS
debug3: Ignored env LD_LIBRARY_PATH
debug3: Ignored env SSH_AUTH_SOCK
debug3: Ignored env _JAVA_OPTIONS
debug3: Ignored env SESSION_MANAGER
debug3: Ignored env PATH
debug3: Ignored env MAIL
debug3: Ignored env DESKTOP_SESSION
debug3: Ignored env QT_IM_MODULE
debug3: Ignored env PWD
debug1: Sending env XMODIFIERS = @im=fcitx
debug2: channel 0: request env confirm 0
debug1: Sending env LANG = zh_CN.UTF-8
debug2: channel 0: request env confirm 0
debug3: Ignored env KDEDIRS
debug3: Ignored env SSH_ASKPASS
debug3: Ignored env HISTCONTROL
debug3: Ignored env JAVA_FONTS
debug3: Ignored env HOME
debug3: Ignored env XDG_SEAT
debug3: Ignored env SHLVL
debug3: Ignored env GTK_OVERLAY_SCROLLING
debug3: Ignored env LOGNAME
debug3: Ignored env CVS_RSH
debug3: Ignored env QTLIB
debug3: Ignored env QT4_IM_MODULE
debug3: Ignored env DBUS_SESSION_BUS_ADDRESS
debug3: Ignored env LESSOPEN
debug3: Ignored env DISPLAY
debug3: Ignored env XDG_RUNTIME_DIR
debug3: Ignored env XDG_CURRENT_DESKTOP
debug3: Ignored env ORACLE_HOME
debug3: Ignored env GTK_IM_MODULE
debug3: Ignored env COLORTERM
debug3: Ignored env XAUTHORITY
debug3: Ignored env _
debug2: channel 0: request shell confirm 1
debug2: callback done
debug2: channel 0: open confirm rwindow 24576 rmax 32759
debug2: channel_input_status_confirm: type 99 id 0
debug2: PTY allocation request accepted on channel 0
debug2: channel_input_status_confirm: type 99 id 0
debug2: shell request accepted on channel 0
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
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug2: channel 0: rcvd close
debug2: channel 0: close_read
debug2: channel 0: input open -> closed
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
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)

Connection to A.B.C.D closed.        <------- 连接还是被关闭
Transferred: sent 3768, received 1728 bytes, in 0.0 seconds
Bytes per second: sent 116851.3, received 53587.9
debug1: Exit status 1

[moontide]

没有办法，已恢复出厂设置，然后重新配置后，就可以登录了。