usermod -L 技术细节特性说明锁定机制密码字段前加!如!$6$xxx...影响范围仅密码认证PAM 密码验证模块不影响root 切换(su)、SSH 密钥登录、已存在会话解锁命令usermod -U username[rootserver ~]# ifconfig ens160: flags4163UP,BROADCAST,RUNNING,MULTICAST mtu 1500 inet 192.168.88.100 netmask 255.255.255.0 broadcast 192.168.88.255 ether 00:50:56:2b:b5:2d txqueuelen 1000 (Ethernet) RX packets 43089 bytes 3108744 (2.9 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 76113 bytes 8733676 (8.3 MiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 lo: flags73UP,LOOPBACK,RUNNING mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 inet6 ::1 prefixlen 128 scopeid 0x10host loop txqueuelen 1000 (Local Loopback) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 0 bytes 0 (0.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 [rootserver ~]# useradd user3 [rootserver ~]# usermod -L user3 [rootserver ~]# su user3 [user3server root]$ exit exit [rootserver ~]# su - user3 [user3server ~]$ exit logout [rootserver ~]# grep user3 /etc/passwd user3:x:1012:1013::/home/user3:/bin/bash [rootserver ~]# echo 123|passwd --stdin user3 Changing password for user user3. passwd: all authentication tokens updated successfully. [rootserver ~]#[rootserver1 ~]# ssh user3192.168.88.100 The authenticity of host 192.168.88.100 (192.168.88.100) cant be established. ED25519 key fingerprint is SHA256:nW25vf1GUfW59rm9bdZn6JQIgid0wPL5UEO7TR7crQ. This key is not known by any other names Are you sure you want to continue connecting (yes/no/[fingerprint])? yes Warning: Permanently added 192.168.88.100 (ED25519) to the list of known hosts. user3192.168.88.100s password: Last login: Fri Apr 10 11:16:31 2026 [user3server ~]$usermod -L user3 # 锁定密码su user3 # root切换成功不受锁定影响su - user3 # root切换成功不受锁定影响echo 123|passwd --stdin user3 # 重新设置密码自动解锁ssh user3IP # 用新密码登录成功[rootserver ~]# usermod -L user3锁定密码了密码验证不能登录。[user3server ~]$ exit logout Connection to 192.168.88.100 closed. [rootserver1 ~]# ssh user3192.168.88.100 user3192.168.88.100s password: Permission denied, please try again. user3192.168.88.100s password:su 切换不受影响因为用户的Shell还是/bin/bash[rootserver ~]# grep user3 /etc/passwd user3:x:1012:1013::/home/user3:/bin/bash [rootserver ~]# ifconfig ens160: flags4163UP,BROADCAST,RUNNING,MULTICAST mtu 1500 inet 192.168.88.100 netmask 255.255.255.0 broadcast 192.168.88.255 ether 00:50:56:2b:b5:2d txqueuelen 1000 (Ethernet) RX packets 43089 bytes 3108744 (2.9 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 76113 bytes 8733676 (8.3 MiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 lo: flags73UP,LOOPBACK,RUNNING mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 inet6 ::1 prefixlen 128 scopeid 0x10host loop txqueuelen 1000 (Local Loopback) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 0 bytes 0 (0.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 [rootserver ~]# su - user3 [user3server ~]$ pwd /home/user3 [user3server ~]$再次改user3密码自动解锁密码限制。