ubuntu启用ssh

镜像源更换

刚安装ubuntu系统时，发现很多命令都无法使用，查询之后，发现是ubuntu系统默认的官方源位于国外，用户访问延时高，因此一般要更换国内的镜像源。
清华源：https://mirrors.tuna.tsinghua.edu.cn/help/ubuntu/

1. 备份当前的源列表：

sudo cp /etc/apt/sources.list.d/ubuntu.sources /etc/apt/sources.list.d/ubuntu.sources.backup

2. 查看当前操作系统版本:

lsb_release -a

3. 编辑镜像源配置文件

sudo nano /etc/apt/sources.list.d/ubuntu.sources

4. 替换为清华大学镜像源（DEB822 格式）,注释对应的noble noble-updates noble-backports段落

Types: deb
URIs: https://mirrors.tuna.tsinghua.edu.cn/ubuntu
Suites: noble noble-updates noble-backports
Components: main restricted universe multiverse
Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg

5. 保存并退出编辑器

   • 按 Ctrl + O 保存文件
   • 按 Ctrl + X 退出 nano 编辑器

6. 更新

sudo apt update

提供ssh连接信息

1. 查看服务器的 IP 地址:172.30.114.33

ip addr show

jessie@jessie:~$ ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00inet 127.0.0.1/8 scope host lovalid_lft forever preferred_lft foreverinet6 ::1/128 scope host noprefixroute valid_lft forever preferred_lft forever
2: enp0s31f6: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000link/ether 20:88:10:93:70:bf brd ff:ff:ff:ff:ff:ffinet 172.30.114.33/24 brd 172.30.114.255 scope global dynamic noprefixroute enp0s31f6valid_lft 2629sec preferred_lft 2629secinet6 2001:250:3c00:3840:13b9:8c0a:55d5:c228/64 scope global temporary dynamic valid_lft 3348sec preferred_lft 3348secinet6 2001:250:3c00:3840:2288:10ff:fe93:70bf/64 scope global dynamic mngtmpaddr valid_lft 3348sec preferred_lft 3348secinet6 fe80::2288:10ff:fe93:70bf/64 scope link valid_lft forever preferred_lft forever
3: wlp2s0: <BROADCAST,MULTICAST> mtu 1500 qdisc noqueue state DOWN group default qlen 1000link/ether 4c:82:a9:72:a1:23 brd ff:ff:ff:ff:ff:ff
jessie@jessie:~$ 

2. 安装 OpenSSH 服务

sudo apt install openssh-server

3. 检查 OpenSSH 服务状态

jessie@jessie:~$ sudo systemctl status ssh
○ ssh.service - OpenBSD Secure Shell serverLoaded: loaded (/usr/lib/systemd/system/ssh.service; disabled; preset: enabled)Active: inactive (dead)
TriggeredBy: ● ssh.socketDocs: man:sshd(8)man:sshd_config(5)

如果没有启动inactive (dead)

jessie@jessie:~$ sudo systemctl start ssh

然后查看

jessie@jessie:~$ sudo systemctl start ssh
jessie@jessie:~$ sudo systemctl status ssh
● ssh.service - OpenBSD Secure Shell serverLoaded: loaded (/usr/lib/systemd/system/ssh.service; disabled; preset: enabled)Active: active (running) since Thu 2025-07-17 15:53:36 CST; 10s ago
TriggeredBy: ● ssh.socketDocs: man:sshd(8)man:sshd_config(5)Process: 31524 ExecStartPre=/usr/sbin/sshd -t (code=exited, status=0/SUCCESS)Main PID: 31525 (sshd)Tasks: 1 (limit: 18579)Memory: 1.2M (peak: 1.7M)CPU: 31msCGroup: /system.slice/ssh.service└─31525 "sshd: /usr/sbin/sshd -D [listener] 0 of 10-100 startups"7月 17 15:53:36 jessie systemd[1]: Starting ssh.service - OpenBSD Secure Shell server...
7月 17 15:53:36 jessie sshd[31525]: Server listening on :: port 22.
7月 17 15:53:36 jessie systemd[1]: Started ssh.service - OpenBSD Secure Shell server.

4. 设置 OpenSSH 服务开机自启

jessie@jessie:~$ sudo systemctl enable ssh
Synchronizing state of ssh.service with SysV service script with /usr/lib/systemd/systemd-sysv-install.
Executing: /usr/lib/systemd/systemd-sysv-install enable ssh
Created symlink /etc/systemd/system/sshd.service → /usr/lib/systemd/system/ssh.service.
Created symlink /etc/systemd/system/multi-user.target.wants/ssh.service → /usr/lib/systemd/system/ssh.service.

5. 检查防火墙设置（如有）

sudo ufw allow ssh
sudo ufw status

6. 确认 SSH 配置文件

sudo nano /etc/ssh/sshd_config
#Port 22 默认端口是 22

7. 查看当前系统的用户名

whoami

8. 下载finalshell连接

ssh jessie@172.30.114.33 port=22