19 strings / 930 words

Translation Source string Target string
Linux From Scratch 12.3/chapter09_symlinks — Chinese (Simplified Han script)
Udev, by default, names network devices according to Firmware/BIOS data or physical characteristics like the bus, slot, or MAC address. The purpose of this naming convention is to ensure that network devices are named consistently, not based on when the network card was discovered. In older versions of Linux—on a computer with two network cards made by Intel and Realtek, for instance—the network card manufactured by Intel might have become eth0 while the Realtek card became eth1. After a reboot, the cards would sometimes get renumbered the other way around.
Udev 在默认情况下，根据固件或 BIOS 的数据，或总线、插槽与 MAC 地址等物理特性命名网络设备。这种命名法的主要目的是保证网络设备在每次引导时获得一致的命名，而不是基于网卡被系统发现的时间进行命名。例如，在老式命名方法中，如果一台计算机拥有两块网卡，其中一块由 Intel 生产，另一块由 Realtek 生产，则 Intel 网卡可能被命名为 eth0，而 Realtek 网卡被命名为 eth1。然而在重新启动系统后，它们的顺序可能会颠倒。
Linux From Scratch 12.3/chapter09_symlinks — Chinese (Simplified Han script)
In the new naming scheme, typical network device names are something like enp5s0 or wlp3s0. If this naming convention is not desired, the traditional naming scheme, or a custom scheme, can be implemented.
在新的命名架构中，典型的网络设备名称就像 enp5s0 或 wlp3s0 这样。如果您不喜欢这种命名惯例，可以采用传统或自定义命名架构。
Linux From Scratch 12.3/chapter09_symlinks — Chinese (Simplified Han script)
The traditional naming scheme using eth0, eth1, etc. can be restored by adding <userinput>net.ifnames=0</userinput> on the kernel command line. This is most appropriate for systems that have just one ethernet device of a particular type. Laptops often have two ethernet connections named eth0 and wlan0; such laptops can also use this method. The command line is in the GRUB configuration file. See <xref linkend="grub-cfg" role='.'/>
传统的，如同 eth0，eth1 这样的命名架构可以通过在内核命令行中加入 <userinput>net.ifnames=0</userinput> 而恢复。这在那些没有两块同类以太网设备的机器上最为合适。笔记本一般拥有两个以太网连接，在这种命名方式下分别是 eth0 和 wlan0，也可以采用这种方法。内核命令行需要写入 GRUB 配置文件中，参阅 <xref linkend="grub-cfg"/>。
Linux From Scratch 12.3/chapter09_symlinks — Chinese (Simplified Han script)
<userinput>bash /usr/lib/udev/init-net-rules.sh</userinput>
<userinput>bash /lib/udev/init-net-rules.sh</userinput>
Linux From Scratch 12.3/chapter09_symlinks — Chinese (Simplified Han script)
In some cases, such as when MAC addresses have been assigned to a network card manually, or in a virtual environment such as Qemu or Xen, the network rules file may not be generated because addresses are not consistently assigned. In these cases, this method cannot be used.
某些情况下，例如 MAC 地址被手动指定给了某块网卡，或在 Qemu、Xen 等虚拟环境下，可能不会生成网络设备规则文件，因为 MAC 地址的分配没有一致性。此时不能使用本方法。
Linux From Scratch 12.3/chapter09_symlinks — Chinese (Simplified Han script)
The file begins with a comment block, followed by two lines for each NIC. The first line for each NIC is a commented description showing its hardware IDs (e.g. its PCI vendor and device IDs, if it's a PCI card), along with its driver (in parentheses, if the driver can be found). Neither the hardware ID nor the driver is used to determine which name to give an interface; this information is only for reference. The second line is the udev rule that matches this NIC and actually assigns it a name.
该文件的开头是一个注释块，之后对于每个网络接口设备 (NIC) 都给出两行。第一行是注释，给出该 NIC 的硬件 ID (例如对于 PCI 设备，就是 PCI 生产商 ID 和设备 ID)，如果能找到驱动程序的话，也会在括号中给出。它们并不被用于确定该设备的命名，仅供您在编写规则时进行参考。第二行是匹配该 NIC 的 udev 规则，和实际赋予它的设备名。
Linux From Scratch 12.3/chapter09_symlinks — Chinese (Simplified Han script)
All udev rules are made up of several keywords, separated by commas and optional whitespace. Here are the keywords, and an explanation of each one:
所有 udev 规则包含若干键值，用逗号和可选的空格进行分隔。下面给出规则中包含的键值和对它们的解释：
Linux From Scratch 12.3/chapter09_symlinks — Chinese (Simplified Han script)
<literal>DRIVERS=="?*"</literal> - This exists so that udev will ignore VLAN or bridge sub-interfaces (because these sub-interfaces do not have drivers). These sub-interfaces are skipped because the name that would be assigned would collide with the parent devices.
<literal>DRIVERS=="?*"</literal> - 这使得 udev 忽略 VLAN 或桥接子接口 (它们没有驱动程序)。它们必须被忽略，否则其命名会与父设备冲突。
Linux From Scratch 12.3/chapter09_symlinks — Chinese (Simplified Han script)
<literal>ATTR{address}</literal> - The value of this keyword is the NIC's MAC address.
<literal>ATTR{address}</literal> - 该键的值是 NIC 的 MAC 地址。
Linux From Scratch 12.3/chapter09_symlinks — Chinese (Simplified Han script)
<literal>NAME</literal> - The value of this keyword is the name that udev will assign to this interface.
<literal>NAME</literal> - 该键的值是 udev 将赋予该网络接口的命名。
Linux From Scratch 12.3/chapter09_symlinks — Chinese (Simplified Han script)
The value of <literal>NAME</literal> is the important part. Make sure you know which name has been assigned to each of your network cards before proceeding, and be sure to use that <literal>NAME</literal> value when creating your network configuration files.
<literal>NAME</literal> 的值是我们关注的重点。在继续阅读之前，您需要确保自己知道赋予每个网络接口的命名，在之后的配置文件中需要使用这些名称作为 <literal>NAME</literal> 的值。
Linux From Scratch 12.3/chapter09_symlinks — Chinese (Simplified Han script)
Even if the custom udev rule file is created, udev may still assign one or more alternative names for a NIC based on physical characteristics. If a custom udev rule would rename some NIC using a name already assigned as an alternative name of another NIC, this udev rule will fail. If this issue happens, you may create the <filename>/etc/udev/network/99-default.link</filename> configuration file with an empty alternative assignment policy, overriding the default configuration file <filename>/usr/lib/udev/network/99-default.link</filename>:
 
Linux From Scratch 12.3/chapter09_symlinks — Chinese (Simplified Han script)
<userinput>sed -e '/^AlternativeNamesPolicy/s/=.*$/=/' \
/usr/lib/udev/network/99-default.link \
> /etc/udev/network/99-default.link</userinput>
 
Linux From Scratch 12.3/chapter09_symlinks — Chinese (Simplified Han script)
CD-ROM Symlinks
CD-ROM 符号链接
Linux From Scratch 12.3/chapter09_symlinks — Chinese (Simplified Han script)
Some software that you may want to install later (e.g., various media players) expects the <filename class="symlink">/dev/cdrom</filename> and <filename class="symlink">/dev/dvd</filename> symlinks to exist, and to point to a CD-ROM or DVD-ROM device. Also, it may be convenient to put references to those symlinks into <filename>/etc/fstab</filename>. Udev comes with a script that will generate rules files to create these symlinks for you, depending on the capabilities of each device, but you need to decide which of two modes of operation you wish to have the script use.
您之后可能希望安装的一些程序 (如某些媒体播放器) 预期 <filename class="symlink">/dev/cdrom</filename> 和 <filename class="symlink">/dev/dvd</filename> 符号链接存在，并指向 CD-ROM 或 DVD-ROM 设备。另外，在 <filename>/etc/fstab</filename> 中引用它们也非常方便。Udev 提供了一个脚本，能根据每个设备的功能，为您生成创建这两个符号链接的规则。但是，您需要确定，自己希望使用该脚本提供的两种操作模式中的哪一种。
Linux From Scratch 12.3/chapter09_symlinks — Chinese (Simplified Han script)
There are advantages to each approach; the correct approach depends on what kinds of device changes may happen. If you expect the physical path to the device (that is, the ports and/or slots that it plugs into) to change, for example because you plan on moving the drive to a different IDE port or a different USB connector, then you should use the <quote>by-id</quote> mode. On the other hand, if you expect the device's identification to change, for example because it may die, and you intend to replace it with a different device that plugs into the same connectors, then you should use the <quote>by-path</quote> mode.
两种方式各有优缺点，正确地方式依赖于设备可能发生的变化。如果您预期指向设备的物理路径 (即它连接的端口或插槽) 可能变化，例如您可能会将它移动到另一个 IDE 接口或另一个 USB 接口，您应该使用 <quote>by-id</quote> 模式。另一方面，如果您可能用具有相同功能，并接入相同接口的另一台设备替换它，则您应该使用 <quote>by-path</quote> 模式。
Linux From Scratch 12.3/chapter09_symlinks — Chinese (Simplified Han script)
However, if you have multiple CD-ROM devices, then the symlinks generated at that time may point to different devices than they point to on your host because devices are not discovered in a predictable order. The assignments created when you first boot the LFS system will be stable, so this is only an issue if you need the symlinks on both systems to point to the same device. If you need that, then inspect (and possibly edit) the generated <filename>/etc/udev/rules.d/70-persistent-cd.rules</filename> file after booting, to make sure the assigned symlinks match your needs.
然而，如果您有多个 CD-ROM 设备，则生成的符号链接可能指向不同于您的宿主系统的设备，因为设备发现的顺序不可预测。在您第一次引导 LFS 系统后，创建的设备分配将会是稳定的，因此这仅在您希望宿主系统和 LFS 中的符号链接指向同一设备时才会成为问题。如果您有这种需求，在引导后检查 (如果需要的话修改) 生成的 <filename>/etc/udev/rules.d/70-persistent-cd.rules</filename> 文件，保证分配的符号链接和您的需要一致。
Linux From Scratch 12.3/chapter09_symlinks — Chinese (Simplified Han script)
Dealing with Duplicate Devices
处理重复设备
Linux From Scratch 12.3/chapter09_symlinks — Chinese (Simplified Han script)
As explained in <xref linkend="ch-config-udev" role=','/> the order in which devices with the same function appear in <filename class="directory">/dev</filename> is essentially random. E.g., if you have a USB web camera and a TV tuner, sometimes <filename>/dev/video0</filename> refers to the camera and <filename>/dev/video1</filename> refers to the tuner, and sometimes after a reboot the order changes. For all classes of hardware except sound cards and network cards, this is fixable by creating udev rules to create persistent symlinks. The case of network cards is covered separately in <xref linkend="ch-config-network" role=','/> and sound card configuration can be found in <ulink url="&blfs-book;postlfs/devices.html">BLFS</ulink>.
正如<xref linkend="ch-config-udev"/>中所述，那些功能相同的设备在 <filename class="directory">/dev</filename> 中的顺序是随机的。例如，如果您有一个 USB 摄像头和一个电视棒，有时 <filename>/dev/video0</filename> 会指向摄像头，<filename>/dev/video1</filename> 指向电视棒，而有时在重启后这个顺序正好颠倒过来。对于所有除了声卡和网卡以外的设备，该问题都可以通过创建自定义持久化符号链接的 Udev 规则来解决。对于网卡的解决方案在<xref linkend="ch-config-network"/>中单独描述，而声卡配置可以在 <ulink url="&blfs-book;postlfs/devices.html">BLFS</ulink> 中找到。