From eaafab91144f0209f21f74302392928ec9f0d5ad Mon Sep 17 00:00:00 2001 From: zhengchiliu <857493511@qq.com> Date: Fri, 8 Aug 2025 00:41:18 +0800 Subject: [PATCH] 20250808 --- 运维/操作系统/Linux/排障/ssh免密无法登录.md | 126 ++++++++++++++++++++ 1 file changed, 126 insertions(+) create mode 100644 运维/操作系统/Linux/排障/ssh免密无法登录.md diff --git a/运维/操作系统/Linux/排障/ssh免密无法登录.md b/运维/操作系统/Linux/排障/ssh免密无法登录.md new file mode 100644 index 0000000..da13ea7 --- /dev/null +++ b/运维/操作系统/Linux/排障/ssh免密无法登录.md @@ -0,0 +1,126 @@ +# SSH免密无法登录 + +时间：2025年8月8日 + +------ + +记录一次SSH免密无法登录处理过程 + +## 现象 + +提交git仓代码时发现需要输入密码，检查git公钥私钥正常，怀疑gitea bug，删除gitea账户的密钥后，仍失败 + +![image-20250808001918017](C:\Users\85749\AppData\Roaming\Typora\typora-user-images\image-20250808001918017.png) + +## 排查过程 + +1、查看本机密钥权限是否存在异常 + +``` +root@VM-2-16-ubuntu:~/.ssh# ll +total 24 +drwx------ 2 root root 4096 Aug 7 23:56 ./ +drwx------ 25 root root 4096 Aug 7 23:51 ../ +-rw------- 1 root root 777 Dec 13 2024 authorized_keys +-rw------- 1 root root 411 Nov 19 2024 id_ed25519 +###权限正常600 -> 411 +-rw-r--r-- 1 root root 101 Nov 19 2024 id_ed25519.pub +-rw-r--r-- 1 root root 142 Aug 7 23:56 known_hosts +``` + +2、查看本机公钥私钥是否匹配 + +``` +root@VM-2-16-ubuntu:~/.ssh# cat id_ed25519.pub +ssh-ed25519 AAAAAAAAAAAAAAAAAAAAAAAAAAAAAA root@VM-2-16-ubuntu + +ssh-keygen -y -f ~/.ssh/id_ed25519 +ssh-ed25519 AAAAAAAAAAAAAAAAAAAAAAAAAA root@VM-2-16-ubuntu + +###密钥结果匹配，本机无异常 +``` + +3、查看本机debug日志 + +``` +root@VM-2-16-ubuntu:~/.ssh# ssh -vT -i ~/.ssh/id_ed25519 git@git.lzcwy.cn +OpenSSH_9.6p1 Ubuntu-3ubuntu13.5, OpenSSL 3.0.13 30 Jan 2024 +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 * +debug1: Connecting to git.lzcwy.cn [82.157.64.204] port 22. +debug1: Connection established. +debug1: identity file /root/.ssh/id_ed25519 type 3 +debug1: identity file /root/.ssh/id_ed25519-cert type -1 +debug1: Local version string SSH-2.0-OpenSSH_9.6p1 Ubuntu-3ubuntu13.5 +debug1: Remote protocol version 2.0, remote software version OpenSSH_9.6p1 Ubuntu-3ubuntu13.13 +debug1: compat_banner: match: OpenSSH_9.6p1 Ubuntu-3ubuntu13.13 pat OpenSSH* compat 0x04000000 +debug1: Authenticating to git.lzcwy.cn:22 as 'git' +debug1: load_hostkeys: fopen /root/.ssh/known_hosts2: No such file or directory +debug1: load_hostkeys: fopen /etc/ssh/ssh_known_hosts: No such file or directory +debug1: load_hostkeys: fopen /etc/ssh/ssh_known_hosts2: No such file or directory +debug1: SSH2_MSG_KEXINIT sent +debug1: SSH2_MSG_KEXINIT received +debug1: kex: algorithm: sntrup761x25519-sha512@openssh.com +debug1: kex: host key algorithm: ssh-ed25519 +debug1: kex: server->client cipher: chacha20-poly1305@openssh.com MAC: compression: none +debug1: kex: client->server cipher: chacha20-poly1305@openssh.com MAC: compression: none +debug1: expecting SSH2_MSG_KEX_ECDH_REPLY +debug1: SSH2_MSG_KEX_ECDH_REPLY received +debug1: Server host key: ssh-ed25519 SHA256:KeQo88NlFRuNnUykhPUh2o0dyWazhH9OIvIPklUD4w4 +debug1: load_hostkeys: fopen /root/.ssh/known_hosts2: No such file or directory +debug1: load_hostkeys: fopen /etc/ssh/ssh_known_hosts: No such file or directory +debug1: load_hostkeys: fopen /etc/ssh/ssh_known_hosts2: No such file or directory +debug1: Host 'git.lzcwy.cn' is known and matches the ED25519 host key. +debug1: Found key in /root/.ssh/known_hosts:1 +debug1: ssh_packet_send2_wrapped: resetting send seqnr 3 +debug1: rekey out after 134217728 blocks +debug1: SSH2_MSG_NEWKEYS sent +debug1: Sending SSH2_MSG_EXT_INFO +debug1: expecting SSH2_MSG_NEWKEYS +debug1: ssh_packet_read_poll2: resetting read seqnr 3 +debug1: SSH2_MSG_NEWKEYS received +debug1: rekey in after 134217728 blocks +debug1: SSH2_MSG_EXT_INFO received +debug1: kex_ext_info_client_parse: server-sig-algs= +debug1: kex_ext_info_check_ver: publickey-hostbound@openssh.com=<0> +debug1: kex_ext_info_check_ver: ping@openssh.com=<0> +debug1: SSH2_MSG_SERVICE_ACCEPT received +debug1: SSH2_MSG_EXT_INFO received +debug1: kex_ext_info_client_parse: server-sig-algs= +debug1: Authentications that can continue: publickey,password +debug1: Next authentication method: publickey +debug1: Will attempt key: /root/.ssh/id_ed25519 ED25519 SHA256:w2mqdrO/ZGBBofMzBXHkEIyuoSudfgtF3rTr5Tlr6eE explicit +debug1: Offering public key: /root/.ssh/id_ed25519 ED25519 SHA256:w2mqdrO/ZGBBofMzBXHkEIyuoSudfgtF3rTr5Tlr6eE explicit +debug1: Authentications that can continue: publickey,password +debug1: Next authentication method: password +git@git.lzcwy.cn's password: + +###debug1: Offering public key: /root/.ssh/id_ed25519 ED25519 说明本机可以识别到密钥并正确发送，查看对端日志 +``` + +4、查看对端ssh日志 + +``` +root@VM-24-13-ubuntu:/home/ubuntu# tail -f /var/log/auth.log + +2025-08-07T23:50:16.251031+08:00 localhost sshd[553036]: User git not allowed because account is locked + +###账号被锁定了 +``` + +5、查看账号状态 + +``` +root@VM-24-13-ubuntu:/home/ubuntu# passwd -S git +git L 2024-12-31 -1 -1 -1 -1 + +###L为被Lock，解锁账号 +``` + +6、解锁账号恢复 + +``` +usermod -p 密码 git +``` +