如何完全删除Linux系统中所有OpenVPN服务端及客户端相关残留文件

问题描述 #

我误在电脑上安装了OpenVPN的服务端和客户端，现在想要彻底删除设备上所有与openvpn-server、openvpn-client相关的内容。
我已经执行了如下命令：

$ sudo apt remove openvpn
$ sudo apt purge openvpn
$ sudo apt autoremove openvpn

但执行完成后仍然有大量相关文件残留：

$ sudo find / -type d -name "openvpn*" 2>/dev/null

sys/fs/cgroup/devices/system.slice/openvpn-iptables.service
/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service
/sys/fs/cgroup/pids/system.slice/openvpn-iptables.service
/sys/fs/cgroup/systemd/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service
/sys/fs/cgroup/systemd/system.slice/openvpn-iptables.service
/sys/fs/cgroup/unified/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service
/sys/fs/cgroup/unified/system.slice/openvpn-iptables.service

我执行sudo updatedb更新数据库后，再使用locate openvpn无法检索到这些文件。随后我尝试执行如下命令删除这些文件：

$ sudo rm -rf $(sudo find / -type d -name "openvpn*" 2>/dev/null/)
$ sudo rm -r $(sudo find / -type d -name "openvpn*" 2>/dev/null/)
$ sudo rm -f $(sudo find / -type d -name "openvpn*" 2>/dev/null/)

但文件仍然没有被删除，系统返回了如下报错：

rm: cannot remove '/sys/fs/cgroup/devices/system.slice/openvpn-iptables.service/cgroup.procs': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/devices/system.slice/openvpn-iptables.service/devices.deny': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/devices/system.slice/openvpn-iptables.service/devices.list': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/devices/system.slice/openvpn-iptables.service/devices.allow': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/devices/system.slice/openvpn-iptables.service/tasks': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/devices/system.slice/openvpn-iptables.service/notify_on_release': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/devices/system.slice/openvpn-iptables.service/cgroup.clone_children': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/cgroup.procs': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.use_hierarchy': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.kmem.tcp.usage_in_bytes': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.soft_limit_in_bytes': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.force_empty': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.pressure_level': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.move_charge_at_immigrate': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.memsw.failcnt': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.kmem.tcp.max_usage_in_bytes': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.max_usage_in_bytes': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.oom_control': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.stat': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.kmem.slabinfo': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.limit_in_bytes': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.swappiness': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.memsw.max_usage_in_bytes': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.numa_stat': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.kmem.failcnt': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.kmem.max_usage_in_bytes': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.usage_in_bytes': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/tasks': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.memsw.limit_in_bytes': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.failcnt': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/cgroup.event_control': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.kmem.tcp.failcnt': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.kmem.limit_in_bytes': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.memsw.usage_in_bytes': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/notify_on_release': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.kmem.usage_in_bytes': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/memory.kmem.tcp.limit_in_bytes': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/memory/system.slice/openvpn-iptables.service/cgroup.clone_children': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/pids/system.slice/openvpn-iptables.service/cgroup.procs': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/pids/system.slice/openvpn-iptables.service/pids.current': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/pids/system.slice/openvpn-iptables.service/pids.events': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/pids/system.slice/openvpn-iptables.service/tasks': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/pids/system.slice/openvpn-iptables.service/notify_on_release': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/pids/system.slice/openvpn-iptables.service/pids.max': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/pids/system.slice/openvpn-iptables.service/cgroup.clone_children': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/systemd/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service/cgroup.procs': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/systemd/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service/tasks': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/systemd/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service/notify_on_release': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/systemd/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service/cgroup.clone_children': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/systemd/system.slice/openvpn-iptables.service/cgroup.procs': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/systemd/system.slice/openvpn-iptables.service/tasks': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/systemd/system.slice/openvpn-iptables.service/notify_on_release': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/systemd/system.slice/openvpn-iptables.service/cgroup.clone_children': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service/cgroup.events': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service/io.pressure': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service/cgroup.procs': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service/cgroup.max.descendants': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service/cpu.stat': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service/memory.pressure': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service/cpu.pressure': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service/cgroup.type': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service/cgroup.stat': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service/cgroup.threads': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service/cgroup.freeze': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service/cgroup.controllers': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service/cgroup.subtree_control': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/system-openvpn\x2dserver.slice/openvpn-server@server.service/cgroup.max.depth': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/openvpn-iptables.service/cgroup.events': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/openvpn-iptables.service/io.pressure': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/openvpn-iptables.service/cgroup.procs': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/openvpn-iptables.service/cgroup.max.descendants': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/openvpn-iptables.service/cpu.stat': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/openvpn-iptables.service/memory.pressure': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/openvpn-iptables.service/cpu.pressure': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/openvpn-iptables.service/cgroup.type': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/openvpn-iptables.service/cgroup.stat': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/openvpn-iptables.service/cgroup.threads': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/openvpn-iptables.service/cgroup.freeze': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/openvpn-iptables.service/cgroup.controllers': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/openvpn-iptables.service/cgroup.subtree_control': Operation not permitted
rm: cannot remove '/sys/fs/cgroup/unified/system.slice/openvpn-iptables.service/cgroup.max.depth': Operation not permitted

解决方案 #

/sys/fs/cgroup是内核提供的cgroup虚拟文件系统，路径下的所有文件都是系统运行时动态生成的状态记录，不存在于实体磁盘中，也不允许用户直接删除，你遇到的无权限报错属于正常现象，完全不需要尝试删除该路径下的文件。

你之前执行的apt purge+autoremove已经完成了OpenVPN软件本体、配置文件、依赖包的卸载，locate无结果也能证明磁盘上已经没有相关的静态残留文件。

如果需要确认卸载完全并清理剩余的服务条目，按以下步骤操作即可：

1. 检查是否有残留的OpenVPN安装包，无输出即为全部卸载完成：

dpkg -l | grep openvpn

2. 检查是否有残留的systemd服务配置：

systemctl list-unit-files | grep openvpn

3. 如果上一步有输出，执行如下命令清理服务残留：

# 停止相关服务
sudo systemctl stop openvpn-iptables.service openvpn-server@server.service
# 禁用服务自启
sudo systemctl disable openvpn-iptables.service openvpn-server@server.service
# 删除残留的服务配置文件
sudo rm -f /etc/systemd/system/openvpn* /etc/systemd/system/*/openvpn*
# 重载systemd配置
sudo systemctl daemon-reload
# 清理失效的服务状态
sudo systemctl reset-failed

4. 重启系统，/sys/fs/cgroup路径下的相关条目会自动消失，不会再出现在检索结果中。

内容的提问来源于stack exchange，提问作者HARSHAL RATHORE