SSH是什么

为了加强远程连接的安全性，提出的一种加密策略
secure shell

一 直接SSH测试，有固定ip，发现能ping通，但SSH不上

1.1 查看固定ip

1.2 能ping通

1.3 SSH失败

二 尝试安装openssh-server

sudo apt install openssh -y

三安装完后查看SSH服务

3.1 用windterm测试登录

Welcome to Ubuntu 22.04.5 LTS (GNU/Linux 6.8.0-40-generic x86_64)

 * Documentation:  https://help.ubuntu.com
 * Management:     https://landscape.canonical.com
 * Support:        https://ubuntu.com/pro

扩展安全维护（ESM）Applications 未启用。

280 更新可以立即应用。
这些更新中有 203 个是标准安全更新。
要查看这些附加更新，请运行：apt list --upgradable

启用 ESM Apps 来获取未来的额外安全更新
请参见 https://ubuntu.com/esm 或者运行: sudo pro status

New release '24.04.3 LTS' available.
Run 'do-release-upgrade' to upgrade to it.

Last login: Sun Sep  7 13:26:42 2025 from 192.168.80.9

3.2 测试ssh服务

root1@root1-virtual-machine:~$ sudo systemctl status ssh
[sudo] root1 的密码： 
● ssh.service - OpenBSD Secure Shell server
     Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enabled)
     Active: active (running) since Sun 2025-09-07 13:25:17 CST; 22min ago
       Docs: man:sshd(8)
             man:sshd_config(5)
   Main PID: 8563 (sshd)
      Tasks: 1 (limit: 4551)
     Memory: 6.5M
        CPU: 1.005s
     CGroup: /system.slice/ssh.service
             └─8563 "sshd: /usr/sbin/sshd -D [listener] 0 of 10-100 startups"

9月 07 13:25:17 root1-virtual-machine systemd[1]: Starting OpenBSD Secure Shell server...
9月 07 13:25:17 root1-virtual-machine sshd[8563]: Server listening on 0.0.0.0 port 22.
9月 07 13:25:17 root1-virtual-machine sshd[8563]: Server listening on :: port 22.
9月 07 13:25:17 root1-virtual-machine systemd[1]: Started OpenBSD Secure Shell server.
9月 07 13:26:40 root1-virtual-machine sshd[8737]: Accepted password for root1 from 192.168.80.9 port 36834 ssh2
9月 07 13:26:40 root1-virtual-machine sshd[8737]: pam_unix(sshd:session): session opened for user root1(uid=1000) by (uid=0)
9月 07 13:27:08 root1-virtual-machine sshd[8840]: Accepted password for root1 from 192.168.80.1 port 63300 ssh2
9月 07 13:27:08 root1-virtual-machine sshd[8840]: pam_unix(sshd:session): session opened for user root1(uid=1000) by (uid=0)