我正在运行 Linux 的定制主板上开发软件。我通过有线连接的 ssh 访问此主板。我的机器上有一个 USB 以太网适配器，然后以太网电缆连接到此定制主板。我设置了 ssh 密钥，这样就不需要每次都输入密码。一切都运行正常，直到我与该主板共享互联网并运行 git pull 来更新其上的软件。（顺便说一下，这很有效）。在我将 IP 地址改回手动并将旧 IP 放回后，我收到有关主机已更改的警告。这是来自互联网的，因此 IP 不匹配，但它看起来像这样：
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that a host key has just been changed.
The fingerprint for the RSA key sent by the remote host is
51:82:00:1c:7e:6f:ac:ac:de:f1:53:08:1c:7d:55:68.
Please contact your system administrator.
Add correct host key in /Users/isaacalves/.ssh/known_hosts to get rid of this message.
Offending RSA key in /Users/isaacalves/.ssh/known_hosts:12
RSA host key for 104.131.16.158 has changed and you have requested strict checking.
Host key verification failed.
当我尝试 ssh 时，系统不断要求我输入密码，尽管不应该这样。最奇特的部分是当我输入密码时，它不接受。我怎么知道这是正确的密码？因为我使用屏幕串行连接到电路板，并已通过屏幕使用该密码登录。我可以通过屏幕访问电路板（主机），只是屏幕真的很慢，我需要 ssh 来使用 vscode 和其他东西。
我甚至卸载了机器上的 ssh 客户端并重新安装。什么也没发生。我删除了机器上的 known_hosts 文件夹，但没用。主机可以 ssh 到它自己的 IP 地址（不是环回），所以我相信它正在接受 ssh 请求。（除非那里有短路，当它使用自己的 IP 时实际上并没有使用 ssh。但我认为是的）。
如果需要，我可以访问主机和客户端文件。由于工作原因，我已经被这个问题困扰了 3 天，所以任何帮助我都会非常感激。我会发布尽可能多的有用的东西。
SSH 尝试：
ellis77@CB461-EE10955:~/.ssh$ ssh [email protected] -vvv
OpenSSH_8.2p1 Ubuntu-4ubuntu0.2, OpenSSL 1.1.1f 31 Mar 2020
debug1: Reading configuration data /home/ellis77/.ssh/config
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: include /etc/ssh/ssh_config.d/*.conf matched no files
debug1: /etc/ssh/ssh_config line 21: Applying options for *
debug2: resolve_canonicalize: hostname 169.254.132.152 is address
debug2: ssh_connect_direct
debug1: Connecting to 169.254.132.152 [169.254.132.152] port 22.
debug1: Connection established.
debug1: identity file /home/ellis77/.ssh/id_rsa type 0
debug1: identity file /home/ellis77/.ssh/id_rsa-cert type -1
debug1: identity file /home/ellis77/.ssh/id_dsa type -1
debug1: identity file /home/ellis77/.ssh/id_dsa-cert type -1
debug1: identity file /home/ellis77/.ssh/id_ecdsa type -1
debug1: identity file /home/ellis77/.ssh/id_ecdsa-cert type -1
debug1: identity file /home/ellis77/.ssh/id_ecdsa_sk type -1
debug1: identity file /home/ellis77/.ssh/id_ecdsa_sk-cert type -1
debug1: identity file /home/ellis77/.ssh/id_ed25519 type -1
debug1: identity file /home/ellis77/.ssh/id_ed25519-cert type -1
debug1: identity file /home/ellis77/.ssh/id_ed25519_sk type -1
debug1: identity file /home/ellis77/.ssh/id_ed25519_sk-cert type -1
debug1: identity file /home/ellis77/.ssh/id_xmss type -1
debug1: identity file /home/ellis77/.ssh/id_xmss-cert type -1
debug1: Local version string SSH-2.0-OpenSSH_8.2p1 Ubuntu-4ubuntu0.2
debug1: Remote protocol version 2.0, remote software version OpenSSH_8.2p1 Ubuntu-4ubuntu0.2
debug1: match: OpenSSH_8.2p1 Ubuntu-4ubuntu0.2 pat OpenSSH* compat 0x04000000
debug2: fd 3 setting O_NONBLOCK
debug1: Authenticating to 169.254.132.152:22 as 'root'
debug3: hostkeys_foreach: reading file "/home/ellis77/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /home/ellis77/.ssh/known_hosts:1
debug3: load_hostkeys: loaded 1 keys from 169.254.132.152
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: curve25519-sha256,[email protected],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,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],[email protected],[email protected],[email protected],[email protected],[email protected],ssh-ed25519,[email protected],rsa-sha2-512,rsa-sha2-256,ssh-rsa
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],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: curve25519-sha256,[email protected],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
debug2: host key algorithms: rsa-sha2-512,rsa-sha2-256,ssh-rsa,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: curve25519-sha256
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:DJTgdLuz5rpLWLc/y2M7YJMqKu8g77Orjn3CyoRreoU
debug3: hostkeys_foreach: reading file "/home/ellis77/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /home/ellis77/.ssh/known_hosts:1
debug3: load_hostkeys: loaded 1 keys from 169.254.132.152
debug1: Host '169.254.132.152' is known and matches the ECDSA host key.
debug1: Found key in /home/ellis77/.ssh/known_hosts:1
debug3: send packet: type 21
debug2: set_newkeys: mode 1
debug1: rekey out 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 in after 134217728 blocks
debug1: Will attempt key: /home/ellis77/.ssh/id_rsa RSA SHA256:rk0afdhz18RlnxGQ0ejIyPKXNUnLvHDEv3BTu9u1kLY agent
debug1: Will attempt key: /home/ellis77/.ssh/id_dsa
debug1: Will attempt key: /home/ellis77/.ssh/id_ecdsa
debug1: Will attempt key: /home/ellis77/.ssh/id_ecdsa_sk
debug1: Will attempt key: /home/ellis77/.ssh/id_ed25519
debug1: Will attempt key: /home/ellis77/.ssh/id_ed25519_sk
debug1: Will attempt key: /home/ellis77/.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,[email protected],ssh-rsa,rsa-sha2-256,rsa-sha2-512,ssh-dss,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,[email protected]>
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,password
debug3: start over, passed a different list publickey,password
debug3: preferred 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 public key: /home/ellis77/.ssh/id_rsa RSA SHA256:rk0afdhz18RlnxGQ0ejIyPKXNUnLvHDEv3BTu9u1kLY agent
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,password
debug1: Trying private key: /home/ellis77/.ssh/id_dsa
debug3: no such identity: /home/ellis77/.ssh/id_dsa: No such file or directory
debug1: Trying private key: /home/ellis77/.ssh/id_ecdsa
debug3: no such identity: /home/ellis77/.ssh/id_ecdsa: No such file or directory
debug1: Trying private key: /home/ellis77/.ssh/id_ecdsa_sk
debug3: no such identity: /home/ellis77/.ssh/id_ecdsa_sk: No such file or directory
debug1: Trying private key: /home/ellis77/.ssh/id_ed25519
debug3: no such identity: /home/ellis77/.ssh/id_ed25519: No such file or directory
debug1: Trying private key: /home/ellis77/.ssh/id_ed25519_sk
debug3: no such identity: /home/ellis77/.ssh/id_ed25519_sk: No such file or directory
debug1: Trying private key: /home/ellis77/.ssh/id_xmss
debug3: no such identity: /home/ellis77/.ssh/id_xmss: 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
[email protected]'s password:
输入正确的密码后（系统不应该要求输入）：
[email protected]'s password:
debug3: send packet: type 50
debug2: we sent a password packet, wait for reply
debug3: receive packet: type 51
debug1: Authentications that can continue: publickey,password
Permission denied, please try again.
[email protected]'s password:
这是主机的 sshd_config 文件的一部分。请注意，密码验证当前已启用，但我已将其关闭并重新启动 ssh 服务，但它仍然要求输入密码。
# This is the sshd server system-wide configuration file. See
# sshd_config(5) for more information.
# This sshd was compiled with PATH=/usr/local/sbin:/usr/local/bin:/usr/bin
# Logging
SyslogFacility AUTH
LogLevel VERBOSE
# Authentication:
#LoginGraceTime 2m
PermitRootLogin yes
#StrictModes yes
#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
最后，两个 ssh 目录的权限：客户端：
drwxrwxr-x 2 ellis77 ellis77 4096 Jun 17 10:08 .
drwxr-xr-x 27 ellis77 ellis77 4096 Jun 17 09:58 ..
-rw-r--r-- 1 ellis77 ellis77 0 Jun 17 10:07 config
-rw------- 1 ellis77 ellis77 2610 Jun 17 09:59 id_rsa
-rw------- 1 ellis77 ellis77 575 Jun 17 09:59 id_rsa.pub
-rw-r--r-- 1 ellis77 ellis77 222 Jun 17 10:08 known_hosts
主持人：
drwxr-xr-x 2 root root 4096 Sep 14 2020 .
drwxr-xr-x 38 root root 4096 Jun 15 13:01 ..
-rw-r--r-- 1 root root 525809 Aug 31 2020 moduli
-rw-r--r-- 1 root root 1484 Sep 15 2020 ssh_config
-rw------- 1 root root 1381 Sep 14 2020 ssh_host_dsa_key
-rw-r--r-- 1 root root 600 Sep 14 2020 ssh_host_dsa_key.pub
-rw------- 1 root root 505 Sep 14 2020 ssh_host_ecdsa_key
-rw-r--r-- 1 root root 172 Sep 14 2020 ssh_host_ecdsa_key.pub
-rw------- 1 root root 399 Sep 14 2020 ssh_host_ed25519_key
-rw-r--r-- 1 root root 92 Sep 14 2020 ssh_host_ed25519_key.pub
-rw------- 1 root root 2590 Sep 14 2020 ssh_host_rsa_key
-rw-r--r-- 1 root root 564 Sep 14 2020 ssh_host_rsa_key.pub
-rw-r--r-- 1 root root 3126
提前致谢。我很乐意提供任何其他需要的东西。
最后确认主机IP：
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 169.254.132.152 netmask 255.255.0.0 broadcast 169.254.255.255
inet6 fe80::20a:35ff:fe00:122 prefixlen 64 scopeid 0x20<link>
ether 00:0a:35:00:01:22 txqueuelen 1000 (Ethernet)
RX packets 1 bytes 46 (46.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 381 bytes 16730 (16.3 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
device interrupt 27 base 0xb000
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 1 (Local Loopback)
RX packets 212 bytes 18477 (18.0 KiB)
编辑：我刚刚用笔记本电脑登录 SSH（笔记本电脑上没有设置密钥），它接受了密码。所以问题似乎出在我的工作机器上。
答案1
所以这很愚蠢但很微妙。在我与主板共享互联网并运行 dhcpcd 后，我将 USB 以太网连接的 IP 地址重新设置为手动模式，并将地址设置为 169.254.132.152...这是和董事会一样我试图通过 SSH 进入。新手错误。它需要是一个不同的地址，但在使用网络掩码进行掩码后仍然相同...例如 169.254.132.150。然后我们在同一个掩码上，但不会占用同一个地址。这解释了为什么我可以 ping 通，以及为什么它不接受我的“密码”，因为我正在通过 SSH 进入我的连接...而不是我的主板。
提示：当您更改连接的 IP 地址时，请确保拔下 USB 然后重新插入以便进行更新。