树莓派自建 NAS 云盘之——树莓派搭建网络存储盘

跟随这些逐步指导构建你自己的基于树莓派的 NAS 系统。

我将在接下来的这三篇文章中讲述如何搭建一个简便、实用的 NAS 云盘系统。我在这个中心化的存储系统中存储数据，并且让它每晚都会自动的备份增量数据。本系列文章将利用 NFS 文件系统将磁盘挂载到同一网络下的不同设备上，使用 Nextcloud 来离线访问数据、分享数据。

本文主要讲述将数据盘挂载到远程设备上的软硬件步骤。本系列第二篇文章将讨论数据备份策略、如何添加定时备份数据任务。最后一篇文章中我们将会安装 Nextcloud 软件，用户通过 Nextcloud 提供的 web 界面可以方便的离线或在线访问数据。本系列教程最终搭建的 NAS 云盘支持多用户操作、文件共享等功能，所以你可以通过它方便的分享数据，比如说你可以发送一个加密链接，跟朋友分享你的照片等等。

最终的系统架构如下图所示：

硬件

首先需要准备硬件。本文所列方案只是其中一种示例，你也可以按不同的硬件方案进行采购。

最主要的就是树莓派 3，它带有四核 CPU、1G RAM，以及（比较）快速的网络接口。数据将存储在两个 USB 磁盘驱动器上（这里使用 1TB 磁盘）；其中一个磁盘用于每天数据存储，另一个用于数据备份。请务必使用有源 USB 磁盘驱动器或者带附加电源的 USB 集线器，因为树莓派无法为两个 USB 磁盘驱动器供电。

软件

在该社区中最活跃的操作系统当属 Raspbian，便于定制个性化项目。已经有很多 操作指南 讲述如何在树莓派中安装 Raspbian 系统，所以这里不再赘述。在撰写本文时，最新的官方支持版本是 Raspbian Stretch，它对我来说很好使用。

到此，我将假设你已经配置好了基本的 Raspbian 系统并且可以通过 ssh 访问到你的树莓派。

准备 USB 磁盘驱动器

为了更好地读写数据，我建议使用 ext4 文件系统去格式化磁盘。首先，你必须先找到连接到树莓派的磁盘。你可以在 /dev/sd/<x> 中找到磁盘设备。使用命令 fdisk -l，你可以找到刚刚连接的两块 USB 磁盘驱动器。请注意，操作下面的步骤将会清除 USB 磁盘驱动器上的所有数据，请做好备份。

1. <span class="pln">pi@raspberrypi</span><span class="pun">:~</span><span class="pln"> $ </span><span class="kwd">sudo</span><span class="kwd">fdisk</span><span class="pun">-</span><span class="pln">l</span>
2. <span class="pun"><...></span>
3. <span class="typ">Disk</span><span class="pun">/</span><span class="pln">dev</span><span class="pun">/</span><span class="pln">sda</span><span class="pun">:</span><span class="lit">931.5</span><span class="typ">GiB</span><span class="pun">,</span><span class="lit">1000204886016</span><span class="pln"> bytes</span><span class="pun">,</span><span class="lit">1953525168</span><span class="pln"> sectors</span>
4. <span class="typ">Units</span><span class="pun">:</span><span class="pln"> sectors of </span><span class="lit">1</span><span class="pun">*</span><span class="lit">512</span><span class="pun">=</span><span class="lit">512</span><span class="pln"> bytes</span>
5. <span class="typ">Sector</span><span class="kwd">size</span><span class="pun">(</span><span class="pln">logical</span><span class="pun">/</span><span class="pln">physical</span><span class="pun">):</span><span class="lit">512</span><span class="pln"> bytes </span><span class="pun">/</span><span class="lit">512</span><span class="pln"> bytes</span>
6. <span class="pln">I</span><span class="pun">/</span><span class="pln">O </span><span class="kwd">size</span><span class="pun">(</span><span class="pln">minimum</span><span class="pun">/</span><span class="pln">optimal</span><span class="pun">):</span><span class="lit">512</span><span class="pln"> bytes </span><span class="pun">/</span><span class="lit">512</span><span class="pln"> bytes</span>
7. <span class="typ">Disklabel</span><span class="pln"> type</span><span class="pun">:</span><span class="pln"> dos</span>
8. <span class="typ">Disk</span><span class="pln"> identifier</span><span class="pun">:</span><span class="lit">0xe8900690</span>
9. <span class="typ">Device</span><span class="typ">Boot</span><span class="typ">Start</span><span class="typ">End</span><span class="typ">Sectors</span><span class="typ">Size</span><span class="typ">Id</span><span class="typ">Type</span>
10. <span class="pun">/</span><span class="pln">dev</span><span class="pun">/</span><span class="pln">sda1 </span><span class="lit">2048</span><span class="lit">1953525167</span><span class="lit">1953523120</span><span class="lit">931.5G</span><span class="lit">83</span><span class="typ">Linux</span>
11. <span class="typ">Disk</span><span class="pun">/</span><span class="pln">dev</span><span class="pun">/</span><span class="pln">sdb</span><span class="pun">:</span><span class="lit">931.5</span><span class="typ">GiB</span><span class="pun">,</span><span class="lit">1000204886016</span><span class="pln"> bytes</span><span class="pun">,</span><span class="lit">1953525168</span><span class="pln"> sectors</span>
12. <span class="typ">Units</span><span class="pun">:</span><span class="pln"> sectors of </span><span class="lit">1</span><span class="pun">*</span><span class="lit">512</span><span class="pun">=</span><span class="lit">512</span><span class="pln"> bytes</span>
13. <span class="typ">Sector</span><span class="kwd">size</span><span class="pun">(</span><span class="pln">logical</span><span class="pun">/</span><span class="pln">physical</span><span class="pun">):</span><span class="lit">512</span><span class="pln"> bytes </span><span class="pun">/</span><span class="lit">512</span><span class="pln"> bytes</span>
14. <span class="pln">I</span><span class="pun">/</span><span class="pln">O </span><span class="kwd">size</span><span class="pun">(</span><span class="pln">minimum</span><span class="pun">/</span><span class="pln">optimal</span><span class="pun">):</span><span class="lit">512</span><span class="pln"> bytes </span><span class="pun">/</span><span class="lit">512</span><span class="pln"> bytes</span>
15. <span class="typ">Disklabel</span><span class="pln"> type</span><span class="pun">:</span><span class="pln"> dos</span>
16. <span class="typ">Disk</span><span class="pln"> identifier</span><span class="pun">:</span><span class="lit">0x6aa4f598</span>
17. <span class="typ">Device</span><span class="typ">Boot</span><span class="typ">Start</span><span class="typ">End</span><span class="typ">Sectors</span><span class="typ">Size</span><span class="typ">Id</span><span class="typ">Type</span>
18. <span class="pun">/</span><span class="pln">dev</span><span class="pun">/</span><span class="pln">sdb1 </span><span class="pun">*</span><span class="lit">2048</span><span class="lit">1953521663</span><span class="lit">1953519616</span><span class="lit">931.5G</span><span class="lit">83</span><span class="typ">Linux</span>

由于这些设备是连接到树莓派的唯一的 1TB 的磁盘，所以我们可以很容易的辨别出 /dev/sda 和 /dev/sdb 就是那两个 USB 磁盘驱动器。每个磁盘末尾的分区表提示了在执行以下的步骤后如何查看，这些步骤将会格式化磁盘并创建分区表。为每个 USB 磁盘驱动器按以下步骤进行操作（假设你的磁盘也是 /dev/sda 和 /dev/sdb，第二次操作你只要替换命令中的 sda 为 sdb 即可）。

首先，删除磁盘分区表，创建一个新的并且只包含一个分区的新分区表。在 fdisk 中，你可以使用交互单字母命令来告诉程序你想要执行的操作。只需要在提示符 Command(m for help): 后输入相应的字母即可（可以使用 m 命令获得更多详细信息）：

1. <span class="pln">pi@raspberrypi</span><span class="pun">:~</span><span class="pln"> $ </span><span class="kwd">sudo</span><span class="kwd">fdisk</span><span class="pun">/</span><span class="pln">dev</span><span class="pun">/</span><span class="pln">sda</span>
2. <span class="typ">Welcome</span><span class="pln"> to </span><span class="kwd">fdisk</span><span class="pun">(</span><span class="pln">util</span><span class="pun">-</span><span class="pln">linux </span><span class="lit">2.29</span><span class="pun">.</span><span class="lit">2</span><span class="pun">).</span>
3. <span class="typ">Changes</span><span class="pln"> will remain </span><span class="kwd">in</span><span class="pln"> memory only</span><span class="pun">,</span><span class="kwd">until</span><span class="pln"> you decide to </span><span class="kwd">write</span><span class="pln"> them</span><span class="pun">.</span>
4. <span class="typ">Be</span><span class="pln"> careful before </span><span class="kwd">using</span><span class="pln"> the </span><span class="kwd">write</span><span class="pln"> command</span><span class="pun">.</span>
5. <span class="typ">Command</span><span class="pun">(</span><span class="pln">m </span><span class="kwd">for</span><span class="pln"> help</span><span class="pun">):</span><span class="pln"> o</span>
6. <span class="typ">Created</span><span class="pln"> a </span><span class="kwd">new</span><span class="pln"> DOS disklabel </span><span class="kwd">with</span><span class="pln"> disk identifier </span><span class="lit">0x9c310964</span><span class="pun">.</span>
7. <span class="typ">Command</span><span class="pun">(</span><span class="pln">m </span><span class="kwd">for</span><span class="pln"> help</span><span class="pun">):</span><span class="pln"> n</span>
8. <span class="typ">Partition</span><span class="pln"> type</span>
9. <span class="pln">p primary </span><span class="pun">(</span><span class="lit">0</span><span class="pln"> primary</span><span class="pun">,</span><span class="lit">0</span><span class="pln"> extended</span><span class="pun">,</span><span class="lit">4</span><span class="pln"> free</span><span class="pun">)</span>
10. <span class="pln">e extended </span><span class="pun">(</span><span class="pln">container </span><span class="kwd">for</span><span class="pln"> logical partitions</span><span class="pun">)</span>
11. <span class="typ">Select</span><span class="pun">(</span><span class="kwd">default</span><span class="pln"> p</span><span class="pun">):</span><span class="pln"> p</span>
12. <span class="typ">Partition</span><span class="pln"> number </span><span class="pun">(</span><span class="lit">1</span><span class="pun">-</span><span class="lit">4</span><span class="pun">,</span><span class="kwd">default</span><span class="lit">1</span><span class="pun">):</span>
13. <span class="typ">First</span><span class="pln"> sector </span><span class="pun">(</span><span class="lit">2048</span><span class="pun">-</span><span class="lit">1953525167</span><span class="pun">,</span><span class="kwd">default</span><span class="lit">2048</span><span class="pun">):</span>
14. <span class="typ">Last</span><span class="pln"> sector</span><span class="pun">,</span><span class="pun">+</span><span class="pln">sectors </span><span class="kwd">or</span><span class="pun">+</span><span class="kwd">size</span><span class="pun">{</span><span class="pln">K</span><span class="pun">,</span><span class="pln">M</span><span class="pun">,</span><span class="pln">G</span><span class="pun">,</span><span class="pln">T</span><span class="pun">,</span><span class="pln">P</span><span class="pun">}</span><span class="pun">(</span><span class="lit">2048</span><span class="pun">-</span><span class="lit">1953525167</span><span class="pun">,</span><span class="kwd">default</span><span class="lit">1953525167</span><span class="pun">):</span>
15. <span class="typ">Created</span><span class="pln"> a </span><span class="kwd">new</span><span class="pln"> partition </span><span class="lit">1</span><span class="pln"> of type </span><span class="str">'Linux'</span><span class="kwd">and</span><span class="pln"> of </span><span class="kwd">size</span><span class="lit">931.5</span><span class="typ">GiB</span><span class="pun">.</span>
16. <span class="typ">Command</span><span class="pun">(</span><span class="pln">m </span><span class="kwd">for</span><span class="pln"> help</span><span class="pun">):</span><span class="pln"> p</span>
17. <span class="typ">Disk</span><span class="pun">/</span><span class="pln">dev</span><span class="pun">/</span><span class="pln">sda</span><span class="pun">:</span><span class="lit">931.5</span><span class="typ">GiB</span><span class="pun">,</span><span class="lit">1000204886016</span><span class="pln"> bytes</span><span class="pun">,</span><span class="lit">1953525168</span><span class="pln"> sectors</span>
18. <span class="typ">Units</span><span class="pun">:</span><span class="pln"> sectors of </span><span class="lit">1</span><span class="pun">*</span><span class="lit">512</span><span class="pun">=</span><span class="lit">512</span><span class="pln"> bytes</span>
19. <span class="typ">Sector</span><span class="kwd">size</span><span class="pun">(</span><span class="pln">logical</span><span class="pun">/</span><span class="pln">physical</span><span class="pun">):</span><span class="lit">512</span><span class="pln"> bytes </span><span class="pun">/</span><span class="lit">512</span><span class="pln"> bytes</span>
20. <span class="pln">I</span><span class="pun">/</span><span class="pln">O </span><span class="kwd">size</span><span class="pun">(</span><span class="pln">minimum</span><span class="pun">/</span><span class="pln">optimal</span><span class="pun">):</span><span class="lit">512</span><span class="pln"> bytes </span><span class="pun">/</span><span class="lit">512</span><span class="pln"> bytes</span>
21. <span class="typ">Disklabel</span><span class="pln"> type</span><span class="pun">:</span><span class="pln"> dos</span>
22. <span class="typ">Disk</span><span class="pln"> identifier</span><span class="pun">:</span><span class="lit">0x9c310964</span>
23. <span class="typ">Device</span><span class="typ">Boot</span><span class="typ">Start</span><span class="typ">End</span><span class="typ">Sectors</span><span class="typ">Size</span><span class="typ">Id</span><span class="typ">Type</span>
24. <span class="pun">/</span><span class="pln">dev</span><span class="pun">/</span><span class="pln">sda1 </span><span class="lit">2048</span><span class="lit">1953525167</span><span class="lit">1953523120</span><span class="lit">931.5G</span><span class="lit">83</span><span class="typ">Linux</span>
25. <span class="typ">Command</span><span class="pun">(</span><span class="pln">m </span><span class="kwd">for</span><span class="pln"> help</span><span class="pun">):</span><span class="kwd">w</span>
26. <span class="typ">The</span><span class="pln"> partition table has been altered</span><span class="pun">.</span>
27. <span class="typ">Syncing</span><span class="pln"> disks</span><span class="pun">.</span>

现在，我们将用 ext4 文件系统格式化新创建的分区 /dev/sda1：

1. <span class="pln">pi@raspberrypi</span><span class="pun">:~</span><span class="pln"> $ </span><span class="kwd">sudo</span><span class="kwd">mkfs</span><span class="pun">.</span><span class="pln">ext4 </span><span class="pun">/</span><span class="pln">dev</span><span class="pun">/</span><span class="pln">sda1</span>
2. <span class="kwd">mke2fs</span><span class="lit">1.43</span><span class="pun">.</span><span class="lit">4</span><span class="pun">(</span><span class="lit">31</span><span class="pun">-</span><span class="typ">Jan</span><span class="pun">-</span><span class="lit">2017</span><span class="pun">)</span>
3. <span class="typ">Discarding</span><span class="pln"> device blocks</span><span class="pun">:</span><span class="kwd">done</span>
4. <span class="pun"><...></span>
5. <span class="typ">Allocating</span><span class="pln"> group tables</span><span class="pun">:</span><span class="kwd">done</span>
6. <span class="typ">Writing</span><span class="pln"> inode tables</span><span class="pun">:</span><span class="kwd">done</span>
7. <span class="typ">Creating</span><span class="pln"> journal </span><span class="pun">(</span><span class="lit">1024</span><span class="pln"> blocks</span><span class="pun">):</span><span class="kwd">done</span>
8. <span class="typ">Writing</span><span class="pln"> superblocks </span><span class="kwd">and</span><span class="pln"> filesystem accounting information</span><span class="pun">:</span><span class="kwd">done</span>

重复以上步骤后，让我们根据用途来对它们建立标签：

1. <span class="pln">pi@raspberrypi</span><span class="pun">:~</span><span class="pln"> $ </span><span class="kwd">sudo</span><span class="pln"> e2label </span><span class="pun">/</span><span class="pln">dev</span><span class="pun">/</span><span class="pln">sda1 data</span>
2. <span class="pln">pi@raspberrypi</span><span class="pun">:~</span><span class="pln"> $ </span><span class="kwd">sudo</span><span class="pln"> e2label </span><span class="pun">/</span><span class="pln">dev</span><span class="pun">/</span><span class="pln">sdb1 backup</span>

现在，让我们安装这些磁盘并存储一些数据。以我运营该系统超过一年的经验来看，当树莓派启动时（例如在断电后），USB 磁盘驱动器并不是总被挂载，因此我建议使用 autofs 在需要的时候进行挂载。

首先，安装 autofs 并创建挂载点：

1. <span class="pln">pi@raspberrypi</span><span class="pun">:~</span><span class="pln"> $ </span><span class="kwd">sudo</span><span class="pln"> apt install autofs</span>
2. <span class="pln">pi@raspberrypi</span><span class="pun">:~</span><span class="pln"> $ </span><span class="kwd">sudo</span><span class="kwd">mkdir</span><span class="pun">/</span><span class="pln">nas</span>

然后添加下面这行来挂载设备 /etc/auto.master：

1. <span class="str">/nas    /</span><span class="pln">etc</span><span class="pun">/</span><span class="kwd">auto</span><span class="pun">.</span><span class="pln">usb</span>

如果不存在以下内容，则创建 /etc/auto.usb，然后重新启动 autofs 服务：

1. <span class="pln">data </span><span class="pun">-</span><span class="pln">fstype</span><span class="pun">=</span><span class="pln">ext4</span><span class="pun">,</span><span class="pln">rw </span><span class="pun">:</span><span class="str">/dev/</span><span class="pln">disk</span><span class="pun">/</span><span class="pln">by</span><span class="pun">-</span><span class="pln">label</span><span class="pun">/</span><span class="pln">data</span>
2. <span class="pln">backup </span><span class="pun">-</span><span class="pln">fstype</span><span class="pun">=</span><span class="pln">ext4</span><span class="pun">,</span><span class="pln">rw </span><span class="pun">:</span><span class="str">/dev/</span><span class="pln">disk</span><span class="pun">/</span><span class="pln">by</span><span class="pun">-</span><span class="pln">label</span><span class="pun">/</span><span class="pln">backup</span>
3. <span class="pln">pi@raspberrypi3</span><span class="pun">:~</span><span class="pln"> $ </span><span class="kwd">sudo</span><span class="pln"> service autofs restart</span>

现在你应该可以分别访问 /nas/data 以及 /nas/backup 磁盘了。显然，到此还不会令人太兴奋，因为你只是擦除了磁盘中的数据。不过，你可以执行以下命令来确认设备是否已经挂载成功：

1. <span class="pln">pi@raspberrypi3</span><span class="pun">:~</span><span class="pln"> $ </span><span class="kwd">cd</span><span class="pun">/</span><span class="pln">nas</span><span class="pun">/</span><span class="pln">data</span>
2. <span class="pln">pi@raspberrypi3</span><span class="pun">:</span><span class="str">/nas/</span><span class="pln">data $ </span><span class="kwd">cd</span><span class="pun">/</span><span class="pln">nas</span><span class="pun">/</span><span class="pln">backup</span>
3. <span class="pln">pi@raspberrypi3</span><span class="pun">:</span><span class="str">/nas/</span><span class="pln">backup $ </span><span class="kwd">mount</span>
4. <span class="pun"><...></span>
5. <span class="pun">/</span><span class="pln">etc</span><span class="pun">/</span><span class="kwd">auto</span><span class="pun">.</span><span class="pln">usb on </span><span class="pun">/</span><span class="pln">nas type autofs </span><span class="pun">(</span><span class="pln">rw</span><span class="pun">,</span><span class="pln">relatime</span><span class="pun">,</span><span class="pln">fd</span><span class="pun">=</span><span class="lit">6</span><span class="pun">,</span><span class="pln">pgrp</span><span class="pun">=</span><span class="lit">463</span><span class="pun">,</span><span class="kwd">timeout</span><span class="pun">=</span><span class="lit">300</span><span class="pun">,</span><span class="pln">minproto</span><span class="pun">=</span><span class="lit">5</span><span class="pun">,</span><span class="pln">maxproto</span><span class="pun">=</span><span class="lit">5</span><span class="pun">,</span><span class="pln">indirect</span><span class="pun">)</span>
6. <span class="pun"><...></span>
7. <span class="pun">/</span><span class="pln">dev</span><span class="pun">/</span><span class="pln">sda1 on </span><span class="pun">/</span><span class="pln">nas</span><span class="pun">/</span><span class="pln">data type ext4 </span><span class="pun">(</span><span class="pln">rw</span><span class="pun">,</span><span class="pln">relatime</span><span class="pun">,</span><span class="pln">data</span><span class="pun">=</span><span class="pln">ordered</span><span class="pun">)</span>
8. <span class="pun">/</span><span class="pln">dev</span><span class="pun">/</span><span class="pln">sdb1 on </span><span class="pun">/</span><span class="pln">nas</span><span class="pun">/</span><span class="pln">backup type ext4 </span><span class="pun">(</span><span class="pln">rw</span><span class="pun">,</span><span class="pln">relatime</span><span class="pun">,</span><span class="pln">data</span><span class="pun">=</span><span class="pln">ordered</span><span class="pun">)</span>

首先进入对应目录以确保 autofs 能够挂载设备。autofs 会跟踪文件系统的访问记录，并随时挂载所需要的设备。然后 mount 命令会显示这两个 USB 磁盘驱动器已经挂载到我们想要的位置了。

设置 autofs 的过程容易出错，如果第一次尝试失败，请不要沮丧。你可以上网搜索有关教程。

挂载网络存储

现在你已经设置了基本的网络存储，我们希望将它安装到远程 Linux 机器上。这里使用 NFS 文件系统，首先在树莓派上安装 NFS 服务器：

1. <span class="pln">pi@raspberrypi</span><span class="pun">:~</span><span class="pln"> $ </span><span class="kwd">sudo</span><span class="pln"> apt install nfs</span><span class="pun">-</span><span class="pln">kernel</span><span class="pun">-</span><span class="pln">server</span>

然后，需要告诉 NFS 服务器公开 /nas/data 目录，这是从树莓派外部可以访问的唯一设备（另一个用于备份）。编辑 /etc/exports 添加如下内容以允许所有可以访问 NAS 云盘的设备挂载存储：

1. <span class="str">/nas/</span><span class="pln">data </span><span class="pun">*(</span><span class="pln">rw</span><span class="pun">,</span><span class="kwd">sync</span><span class="pun">,</span><span class="pln">no_subtree_check</span><span class="pun">)</span>

更多有关限制挂载到单个设备的详细信息，请参阅 man exports。经过上面的配置，任何人都可以访问数据，只要他们可以访问 NFS 所需的端口：111 和 2049。我通过上面的配置，只允许通过路由器防火墙访问到我的家庭网络的 22 和 443 端口。这样，只有在家庭网络中的设备才能访问 NFS 服务器。

如果要在 Linux 计算机挂载存储，运行以下命令：

1. <span class="pln">you@desktop</span><span class="pun">:~</span><span class="pln"> $ </span><span class="kwd">sudo</span><span class="kwd">mkdir</span><span class="pun">/</span><span class="pln">nas</span><span class="pun">/</span><span class="pln">data</span>
2. <span class="pln">you@desktop</span><span class="pun">:~</span><span class="pln"> $ </span><span class="kwd">sudo</span><span class="kwd">mount</span><span class="pun">-</span><span class="pln">t nfs </span><span class="pun"><</span><span class="pln">raspberry</span><span class="pun">-</span><span class="pln">pi</span><span class="pun">-</span><span class="kwd">hostname</span><span class="pun">-</span><span class="kwd">or</span><span class="pun">-</span><span class="kwd">ip</span><span class="pun">>:</span><span class="str">/nas/</span><span class="pln">data </span><span class="pun">/</span><span class="pln">nas</span><span class="pun">/</span><span class="pln">data</span>

同样，我建议使用 autofs 来挂载该网络设备。如果需要其他帮助，请参看 如何使用 Autofs 来挂载 NFS 共享。

现在你可以在远程设备上通过 NFS 系统访问位于你树莓派 NAS 云盘上的数据了。在后面一篇文章中，我将介绍如何使用 rsync 自动将数据备份到第二个 USB 磁盘驱动器。你将会学到如何使用 rsync 创建增量备份，在进行日常备份的同时还能节省设备空间。

via: https://opensource.com/article/18/7/network-attached-storage-Raspberry-Pi

作者：Manuel Dewald 选题：lujun9972 译者：jrg 校对：wxy

本文由 LCTT 原创编译，Linux中国 荣誉推出