Linux-如何查看Linux系统是否开通sshd服务

方法1、输入`setup`命令查看系统服务配置方法2、查看Linux系统是否开通sshd服务：`systemctl status sshd.service`或者`service sshd status`方法3、检查服务器的22端口是否处于监听状态（SSH默认使用22端口）：`netstat -tuln | grep 22`或者`netstat -an | grep 22`方法4、查看是否有`sshd`进程：`ps -ef | grep sshd`

方法1、输入<code>setup命令查看系统服务配置

输入setup命令，选择系统服务，查看sshd服务前面是否有 *号，有*号表示已开启该服务。

服务前面有 <code>*号表示已开启该服务。

参考资料：https://www.bilibili.com/video/BV1dW411M7xL/?p=13

方法2、查看Linux系统是否开通sshd服务：<code>systemctl status sshd.service或者service sshd status

如果该命令返回类似于active (running)的结果，则表示sshd服务已经在运行中。

<code>[root@sr var]# systemctl status sshd.service# 查看Linux系统是否开通sshd服务

● sshd.service - OpenSSH server daemon

Loaded: loaded (/usr/lib/systemd/system/sshd.service; enabled; vendor preset: enabled)

Active: active (running) since Sat 2021-06-05 09:59:11 CST; 2 years 8 months ago

Docs: man:sshd(8)

man:sshd_config(5)

Main PID: 1138 (sshd)

Tasks: 1

Memory: 7.8M

CGroup: /system.slice/sshd.service

└─1138 /usr/sbin/sshd -D

Mar 01 11:29:45 sr sshd[17514]: Did not receive identification string from XXX.XXX.XXX.XXX port 43992

Mar 01 12:01:05 sr sshd[20428]: Did not receive identification string from XXX.XXX.XXX.XXX port 59472

Mar 01 12:39:53 sr sshd[23931]: Connection closed by XXX.XXX.XXX.XXX port 52504 [preauth]

Mar 01 12:39:55 sr sshd[23934]: Connection closed by XXX.XXX.XXX.XXX port 52518 [preauth]

Mar 01 12:39:56 sr sshd[23937]: Connection closed by XXX.XXX.XXX.XXX port 52524 [preauth]

Mar 01 13:59:54 sr sshd[31209]: Did not receive identification string from XXX.XXX.XXX.XXX port 64001

Mar 01 14:52:51 sr sshd[3621]: Did not receive identification string from XXX.XXX.XXX.XXX port 57980

Mar 01 16:01:59 sr sshd[10113]: Accepted password for root from XXX.XXX.XXX.XXX port 18389 ssh2

Mar 01 16:42:55 sr sshd[13858]: Connection closed by XXX.XXX.XXX.XXX port 36434 [preauth]

Mar 01 16:44:21 sr sshd[14021]: Did not receive identification string from XXX.XXX.XXX.XXX port 10000

[root@sr var]# service sshd status# 查看Linux系统是否开通sshd服务

● sshd.service - OpenSSH server daemon

Loaded: loaded (/usr/lib/systemd/system/sshd.service; enabled; vendor preset: enabled)

Active: active (running) since Sat 2021-06-05 09:59:11 CST; 2 years 8 months ago

Docs: man:sshd(8)

man:sshd_config(5)

Main PID: 1138 (sshd)

Tasks: 1

Memory: 7.8M

CGroup: /system.slice/sshd.service

└─1138 /usr/sbin/sshd -D

Mar 01 11:29:45 sr sshd[17514]: Did not receive identification string from XXX.XXX.XXX.XXX port 43992

Mar 01 12:01:05 sr sshd[20428]: Did not receive identification string from XXX.XXX.XXX.XXX port 59472

Mar 01 12:39:53 sr sshd[23931]: Connection closed by XXX.XXX.XXX.XXX port 52504 [preauth]

Mar 01 12:39:55 sr sshd[23934]: Connection closed by XXX.XXX.XXX.XXX port 52518 [preauth]

Mar 01 12:39:56 sr sshd[23937]: Connection closed by XXX.XXX.XXX.XXX port 52524 [preauth]

Mar 01 13:59:54 sr sshd[31209]: Did not receive identification string from XXX.XXX.XXX.XXX port 64001

Mar 01 14:52:51 sr sshd[3621]: Did not receive identification string from XXX.XXX.XXX.XXX port 57980

Mar 01 16:01:59 sr sshd[10113]: Accepted password for root from XXX.XXX.XXX.XXX port 18389 ssh2

Mar 01 16:42:55 sr sshd[13858]: Connection closed by XXX.XXX.XXX.XXX port 36434 [preauth]

Mar 01 16:44:21 sr sshd[14021]: Did not receive identification string from XXX.XXX.XXX.XXX port 10000

方法3、检查服务器的22端口是否处于监听状态（SSH默认使用22端口）：netstat -tuln | grep 22或者netstat -an | grep 22

如果SSH服务已启用，并且服务器正在监听22端口，将显示类似于0.0.0.0:22或:::22的信息。

<code>[root@sr var]# netstat -tuln | grep 22# 检查服务器的22端口是否处于监听状态

tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN

[root@sr var]# netstat -an | grep 22# 检查服务器的22端口是否处于监听状态

tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN

tcp 0 0 127.0.0.1:60119 127.0.0.1:35322 TIME_WAIT

tcp 0 52 XXX.XXX.XXX.XXX:22 XXX.XXX.XXX.XXX:18389 ESTABLISHED

tcp 0 0 XXX.XXX.XXX.XXX:39116 XXX.XXX.XXX.XXX:60101 ESTABLISHED

tcp 0 0 XXX.XXX.XXX.XXX:32792 XXX.XXX.XXX.XXX:60101 ESTABLISHED

unix 2 [ ACC ] STREAM LISTENING 12258 /run/dbus/system_bus_socket

unix 2 [ ] DGRAM 14221

unix 3 [ ] STREAM CONNECTED 21885622

方法4、查看是否有sshd进程：ps -ef | grep sshd

<code>[root@sr var]# ps -ef | grep sshd# 查看是否有 sshd 进程

root 1138 1 0 2021 ? 00:01:18 /usr/sbin/sshd -D

root 10113 1138 0 16:01 ? 00:00:00 sshd: root@pts/0

root 18104 10115 0 17:27 pts/0 00:00:00 grep --color=auto sshd