WSL2+Systemd支持度测试

缺乏、安全感 2024-04-01 06:21 69阅读 0赞

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#### 文章目录 ####

*  前言
 *  一、systemd是什么？
 *  二、开始测试
 *   *  1.Docker
     *  2.rsyslog
     *  3.systemd-timesyncd
     *  4.cron
     *  5.snap
     *  6.ssh
     *  7.NetworkManager
 *  总结

--------------------

## 前言 ##

最近在研究WSL2开启systemd支持后对于一些组件的支持度，我选了常用的几个和系统自带的几个用来测试。WSL2如何开启systemd支持在我的另一篇博客里。

[WSL2打开systemd支持][WSL2_systemd]

--------------------

## 一、systemd是什么？ ##

systemd即为system daemon,是linux下的一种init软件,由Lennart Poettering带头开发,并在LGPL 2.1及其后续版本许可证下开源发布,开发目标是提供更优秀的框架以表示系统服务间的依赖关系，并依此实现系统初始化时服务的并行启动，同时达到降低Shell的系统开销的效果，最终代替常用的System V与BSD风格init程序。

与多数发行版使用的System V风格init相比，systemd采用了以下新技术： (1) 采用Socket激活式与总线激活式服务，以提高相互依赖的各服务的并行运行性能； (2) 用Cgroups代替PID来追踪进程，因此即使是两次fork之后生成的守护进程也不会脱离systemd的控制。

## 二、开始测试 ##

### 1.Docker ###

Docker是很常用的容器了，对于很多人你来说几乎是必不可少的组件。我安装的是docker-ce，安装方式这里就不列出来了，大家可以自行百度。我使用的版本如下，其它版本暂时没有测试。

Docker version 20.10.20, build 9fdeb9c

systemctl查看docker状态如下：

anold@DESKTOP-G21E46A:~$ systemctl status docker
    ● docker.service - Docker Application Container Engine
         Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: enabled)
         Active: active (running) since Tue 2022-10-25 09:59:27 CST; 5min ago
    TriggeredBy: ● docker.socket
           Docs: https://docs.docker.com
       Main PID: 444 (dockerd)
          Tasks: 17
         Memory: 98.0M
         CGroup: /system.slice/docker.service
                 └─444 /usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock
    
    Oct 25 09:59:27 DESKTOP-G21E46A dockerd[444]: time="2022-10-25T09:59:27.524348100+08:00" level=warning msg="Your kernel does not support cgroup blkio throttle.write_bps_device"
    Oct 25 09:59:27 DESKTOP-G21E46A dockerd[444]: time="2022-10-25T09:59:27.524351100+08:00" level=warning msg="Your kernel does not support cgroup blkio throttle.read_iops_device"
    Oct 25 09:59:27 DESKTOP-G21E46A dockerd[444]: time="2022-10-25T09:59:27.524354700+08:00" level=warning msg="Your kernel does not support cgroup blkio throttle.write_iops_device"
    Oct 25 09:59:27 DESKTOP-G21E46A dockerd[444]: time="2022-10-25T09:59:27.525156700+08:00" level=info msg="Loading containers: start."
    Oct 25 09:59:27 DESKTOP-G21E46A dockerd[444]: time="2022-10-25T09:59:27.609687100+08:00" level=info msg="Default bridge (docker0) is assigned with an IP address 172.17.0.0/16. Daemon option --bip can be used >
    Oct 25 09:59:27 DESKTOP-G21E46A dockerd[444]: time="2022-10-25T09:59:27.640534000+08:00" level=info msg="Loading containers: done."
    Oct 25 09:59:27 DESKTOP-G21E46A dockerd[444]: time="2022-10-25T09:59:27.680304200+08:00" level=info msg="Docker daemon" commit=03df974 graphdriver(s)=overlay2 version=20.10.20
    Oct 25 09:59:27 DESKTOP-G21E46A dockerd[444]: time="2022-10-25T09:59:27.680597600+08:00" level=info msg="Daemon has completed initialization"
    Oct 25 09:59:27 DESKTOP-G21E46A systemd[1]: Started Docker Application Container Engine.
    Oct 25 09:59:27 DESKTOP-G21E46A dockerd[444]: time="2022-10-25T09:59:27.699345300+08:00" level=info msg="API listen on /run/docker.sock"

运行hello-world测试：

sudo docker run hello-world

结果可以正常下载和运行

### 2.rsyslog ###

anold@DESKTOP-G21E46A:~$ systemctl status rsyslog
    ● rsyslog.service - System Logging Service
         Loaded: loaded (/lib/systemd/system/rsyslog.service; enabled; vendor preset: enabled)
         Active: active (running) since Tue 2022-10-25 09:59:26 CST; 8min ago
    TriggeredBy: ● syslog.socket
           Docs: man:rsyslogd(8)
                 https://www.rsyslog.com/doc/
       Main PID: 300 (rsyslogd)
          Tasks: 4 (limit: 9401)
         Memory: 2.6M
         CGroup: /system.slice/rsyslog.service
                 └─300 /usr/sbin/rsyslogd -n -iNONE
    
    Oct 25 09:59:26 DESKTOP-G21E46A systemd[1]: Starting System Logging Service...
    Oct 25 09:59:26 DESKTOP-G21E46A rsyslogd[300]: imuxsock: Acquired UNIX socket '/run/systemd/journal/syslog' (fd 3) from systemd.  [v8.2001.0]
    Oct 25 09:59:26 DESKTOP-G21E46A systemd[1]: Started System Logging Service.
    Oct 25 09:59:26 DESKTOP-G21E46A rsyslogd[300]: rsyslogd's groupid changed to 110
    Oct 25 09:59:26 DESKTOP-G21E46A rsyslogd[300]: rsyslogd's userid changed to 104
    Oct 25 09:59:26 DESKTOP-G21E46A rsyslogd[300]: [origin software="rsyslogd" swVersion="8.2001.0" x-pid="300" x-info="https://www.rsyslog.com"] start

去/var/log目录看一下：

![在这里插入图片描述][b7ddb425358e41839182aacfdac359d2.png]  
不是systemd启动的wsl是没有syslog和auth.log等一众日志的，大家可以前后对比下。目前来看rsyslog服务运行应该是没有问题的。

### 3.systemd-timesyncd ###

anold@DESKTOP-G21E46A:/var/log$ systemctl status systemd-timesyncd
    ● systemd-timesyncd.service - Network Time Synchronization
         Loaded: loaded (/lib/systemd/system/systemd-timesyncd.service; enabled; vendor preset: enabled)
         Active: inactive (dead)
      Condition: start condition failed at Tue 2022-10-25 10:26:40 CST; 2min 23s ago
                 └─ ConditionVirtualization=!container was not met
           Docs: man:systemd-timesyncd.service(8)
    
    Oct 25 10:26:40 DESKTOP-G21E46A systemd[1]: Condition check resulted in Network Time Synchronization being skipped.

`注意：`第一个出问题的服务来了，这个服务是时间同步，默认是从Ubuntu的NTP服务器同步时间的。看看报错：

ConditionVirtualization=!container was not met

意思是不能在容器里启动，之前在wsl里面编译一些东西也提示过说我是容器，不是实体机器，当时没有找到解决办法。不过这个时间同步的问题大家不用担心，wsl始终和计算机一个时间，应该是获取了rtc时间，我还没有遇到时间走偏的情况。

### 4.cron ###

anold@DESKTOP-G21E46A:/var/log$ systemctl status cron
    ● cron.service - Regular background program processing daemon
         Loaded: loaded (/lib/systemd/system/cron.service; enabled; vendor preset: enabled)
         Active: active (running) since Tue 2022-10-25 10:26:40 CST; 9min ago
           Docs: man:cron(8)
       Main PID: 395 (cron)
          Tasks: 1 (limit: 9401)
         Memory: 592.0K
         CGroup: /system.slice/cron.service
                 └─395 /usr/sbin/cron -f
    
    Oct 25 10:26:40 DESKTOP-G21E46A systemd[1]: Started Regular background program processing daemon.
    Oct 25 10:26:40 DESKTOP-G21E46A cron[395]: (CRON) INFO (pidfile fd = 3)
    Oct 25 10:26:40 DESKTOP-G21E46A cron[395]: (CRON) INFO (Running @reboot jobs)
    Oct 25 10:35:01 DESKTOP-G21E46A CRON[1027]: pam_unix(cron:session): session opened for user root by (uid=0)
    Oct 25 10:35:01 DESKTOP-G21E46A CRON[1028]: (root) CMD (command -v debian-sa1 > /dev/null && debian-sa1 1 1)
    Oct 25 10:35:01 DESKTOP-G21E46A CRON[1027]: pam_unix(cron:session): session closed for user root

正常使用，syslog里看到调用了，不过这个组件在wsl里面用处可能没那么大。

### 5.snap ###

anold@DESKTOP-G21E46A:/var/log$ snap list
    Interacting with snapd is not yet supported on Windows Subsystem for Linux.
    This command has been left available for documentation purposes only.

这种方式暂时不支持，有时间研究下。

![在这里插入图片描述][b5ac19f0bea94d48a60755228df2546b.png]  
snapd守护进程是在后台运行的，snap的命令不能用，一方面snap不太好用，绝大多数人用不到就不深入研究了。

### 6.ssh ###

anold@DESKTOP-G21E46A:/var/log$ systemctl status sshd
    ● ssh.service - OpenBSD Secure Shell server
         Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enabled)
         Active: active (running) since Tue 2022-10-25 10:26:40 CST; 19min ago
           Docs: man:sshd(8)
                 man:sshd_config(5)
        Process: 399 ExecStartPre=/usr/sbin/sshd -t (code=exited, status=0/SUCCESS)
       Main PID: 419 (sshd)
          Tasks: 1 (limit: 9401)
         Memory: 3.2M
         CGroup: /system.slice/ssh.service
                 └─419 sshd: /usr/sbin/sshd -D [listener] 0 of 10-100 startups
    
    Oct 25 10:26:40 DESKTOP-G21E46A systemd[1]: Starting OpenBSD Secure Shell server...
    Oct 25 10:26:40 DESKTOP-G21E46A sshd[419]: Server listening on 0.0.0.0 port 22.
    Oct 25 10:26:40 DESKTOP-G21E46A sshd[419]: Server listening on :: port 22.
    Oct 25 10:26:40 DESKTOP-G21E46A systemd[1]: Started OpenBSD Secure Shell server.

守护进程正常，端口绑定正常，不过外部登不进去。原因在配置文件里面：

# Authentication:
    
    #LoginGraceTime 2m
    #PermitRootLogin prohibit-password
    #StrictModes yes
    #MaxAuthTries 6
    #MaxSessions 10
    
    #PubkeyAuthentication yes
    
    # Expect .ssh/authorized_keys2 to be disregarded by default in future.
    #AuthorizedKeysFile     .ssh/authorized_keys .ssh/authorized_keys2
    
    #AuthorizedPrincipalsFile none
    
    #AuthorizedKeysCommand none
    #AuthorizedKeysCommandUser nobody
    
    # For this to work you will also need host keys in /etc/ssh/ssh_known_hosts
    #HostbasedAuthentication no
    # Change to yes if you don't trust ~/.ssh/known_hosts for
    # HostbasedAuthentication
    #IgnoreUserKnownHosts no
    # Don't read the user's ~/.rhosts and ~/.shosts files
    #IgnoreRhosts yes
    
    # To disable tunneled clear text passwords, change to no here!
    PasswordAuthentication no
    #PermitEmptyPasswords no
    
    # Change to yes to enable challenge-response passwords (beware issues with
    # some PAM modules and threads)
    ChallengeResponseAuthentication no
    
    # Kerberos options
    #KerberosAuthentication no
    #KerberosOrLocalPasswd yes
    #KerberosTicketCleanup yes
    #KerberosGetAFSToken no
    
    # GSSAPI options
    #GSSAPIAuthentication no
    #GSSAPICleanupCredentials yes
    #GSSAPIStrictAcceptorCheck yes

看到了吧PasswordAuthentication no，其实wsl不用这种登陆方式，这个功能很鸡肋。不过ssh client正常使用，大家不用担心。

### 7.NetworkManager ###

服务正常，不过在wsl里没啥用。

剩下的不一一列举了，有需要的可以安装试试。

--------------------

## 总结 ##

由于wsl的特殊性，注定不可能向原生linux那样，功能上肯定还会有些限制。不过不影响我们使用绝大多数功能，特别是对于开发人员还是很方便的。

[WSL2_systemd]: https://blog.csdn.net/jiexijihe945/article/details/127490773
[b7ddb425358e41839182aacfdac359d2.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/01/0415bef010904425a73f417943ab36c8.png
[b5ac19f0bea94d48a60755228df2546b.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/01/a76be9f7ef9d4853843eb0d000b9dd46.png