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 *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：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。
[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 -DMar 01 11:29:45 sr sshd[17514]: Did not receive identification string from XXX.XXX.XXX.XXX port 43992Mar 01 12:01:05 sr sshd[20428]: Did not receive identification string from XXX.XXX.XXX.XXX port 59472Mar 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 64001Mar 01 14:52:51 sr sshd[3621]: Did not receive identification string from XXX.XXX.XXX.XXX port 57980Mar 01 16:01:59 sr sshd[10113]: Accepted password for root from XXX.XXX.XXX.XXX port 18389 ssh2Mar 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 -DMar 01 11:29:45 sr sshd[17514]: Did not receive identification string from XXX.XXX.XXX.XXX port 43992Mar 01 12:01:05 sr sshd[20428]: Did not receive identification string from XXX.XXX.XXX.XXX port 59472Mar 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 64001Mar 01 14:52:51 sr sshd[3621]: Did not receive identification string from XXX.XXX.XXX.XXX port 57980Mar 01 16:01:59 sr sshd[10113]: Accepted password for root from XXX.XXX.XXX.XXX port 18389 ssh2Mar 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。
[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 ESTABLISHEDtcp 0 0 XXX.XXX.XXX.XXX:39116 XXX.XXX.XXX.XXX:60101 ESTABLISHEDtcp 0 0 XXX.XXX.XXX.XXX:32792 XXX.XXX.XXX.XXX:60101 ESTABLISHEDunix 2 [ ACC ] STREAM LISTENING 12258 /run/dbus/system_bus_socketunix 2 [ ] DGRAM 14221 unix 3 [ ] STREAM CONNECTED 21885622方法4、查看是否有sshd进程：ps -ef | grep sshd
[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 -Droot 10113 1138 0 16:01 ? 00:00:00 sshd: root@pts/0root 18104 10115 0 17:27 pts/0 00:00:00 grep --color=auto sshd
