Template:OpenWrt1

1 Work with OpenWrt

1.1 Introduction

OpenWrt is a highly extensible GNU/Linux distribution for embedded devices.Unlike many other distributions for routers, OpenWrt is built from the ground up to be a full-featured, easily modifiable operating system for embedded devices. In practice, this means that you can have all the features you need with none of the bloat, powered by a modern Linux kernel. For more details you can refer to:OpenWrt Website.

1.2 System Login

• 串口登录

如果您需要进行内核开发，最好选购一个串口配件，连接了串口，则可以通过串口终端对开发板进行操作。
使用串口模块能有效地提升开发效率，以下是串口模块的连接方法：
接上串口后，您可以选择从串口模块的DC口或者从MicroUSB口 (如果有) 进行供电。

也可以使用USB转串口模块调试，请注意需要使用5V/2A电源给开发板MicroUSB供电。

默认会以 root 用户自动登录，并且没有设置root用户的密码，你可以使用 passwd 命令来设置 root 用户的密码。

第一次运行系统时，系统会自动拓展TF卡上文件系统分区到最大可用空间：

请耐心等待文件系统扩展完成。

• SSH登录

• Web登录

OpenWrt系统支持通过LuCI Web界面进行访问和配置。

默认用户名为root，无需密码，直接点击"Login"按键即可登录。

1.3 Manage Software Packages

OpenWrt has a package management utility: opkg. You can get its details by running the following command:

$ opkg
Package Manipulation:
        update                  Update list of available packages
        upgrade <pkgs>          Upgrade packages
        install <pkgs>          Install package(s)
        configure <pkgs>        Configure unpacked package(s)
        remove <pkgs|regexp>    Remove package(s)
        flag <flag> <pkgs>      Flag package(s)
         <flag>=hold|noprune|user|ok|installed|unpacked (one per invocation)
 
Informational Commands:
        list                    List available packages
        list-installed          List installed packages
        list-upgradable         List installed and upgradable packages
        list-changed-conffiles  List user modified configuration files
        files <pkg>             List files belonging to <pkg>
        search <file|regexp>    List package providing <file>
        find <regexp>           List packages whose name or description matches <regexp>
        info [pkg|regexp]       Display all info for <pkg>
        status [pkg|regexp]     Display all status for <pkg>
        download <pkg>          Download <pkg> to current directory
...

These are just part of the manual. Here are some popular opkg commands.

• Update Package List

Before you install a package you'd better update the package list:

$ opkg update

• Check Available Packages

$ opkg list

At the time of writing there are 3241 packages available.

• Check Installed Packages:

$ opkg list-installed

At the time of writing 124 packages have been installed.

• Install/Delete Packages:

$ opkg install <pkgs>
$ opkg remove <pkgs>

• Check Files Contained in Installed Packages:

$ opkg files <pkg>

• Install Chinese Language Package for LuCI

$ opkg install luci-i18n-base-zh-cn

• Check Changed Files:

$ opkg list-changed-conffiles

• Reference Links:
  • openwrt opkg

1.4 查看系统状态

• 命令行查看CPU温度和频率

$ cpu_freq 
Aavailable frequency(KHz):
        480000 624000 816000 1008000
Current frequency(KHz):
        CPU0 online=1 temp=26548C governor=ondemand freq=624000KHz
        CPU1 online=1 temp=26548C governor=ondemand freq=624000KHz
        CPU2 online=1 temp=26548C governor=ondemand freq=624000KHz
        CPU3 online=1 temp=26548C governor=ondemand freq=624000KHz

上述信息表示当前有4个CPU核在线, 温度均约为26.5摄氏度, 运行的策略均为根据需求来决定运行频率, 当前的运行频率均为624MHz，设置频率的命令如下：

$ cpu_freq -s 1008000
Aavailable frequency(KHz):
        480000 624000 816000 1008000
Current frequency(KHz):
        CPU0 online=1 temp=36702C governor=userspace freq=1008000KHz
        CPU1 online=1 temp=36702C governor=userspace freq=1008000KHz
        CPU2 online=1 temp=36702C governor=userspace freq=1008000KHz
        CPU3 online=1 temp=36702C governor=userspace freq=1008000KHz

These messages mean four CPU cores are working online. Each core's temperature is 26.5 degrees. Each core's governor is on demand and the frequency is 480 MHz.

• OpenWrt-LuCI Web界面查看系统状态

登录OpenWrt-LuCI界面后，点击顶部的 Statistics ---> Graphs，可以查看系统的各种软硬件状态信息(即statistics)，例如:
1) System Load:

2) RAM:

3) CPU Temperature:

Statistics界面对应软件包luci-app-statistics，luci-app-statistics软件包用Collectd工具收集状态数据并且用RRDtool工具将数据渲染为图表。
你可以通过安装额外的collectd-mod-*软件包去使能更多的statistics. All collectd-mod-* packages use the same configuration file: /etc/config/luci_statistics.

• Reference Links:
  • openwrt luci_app_statistics
  • openwrt statistics.chart.public
  • openwrt statistic.custom

1.5 查看Network->Interfaces的配置

• 登录OpenWrt-LuCI界面后，点击顶部的 Network ---> Interfaces ，可以查看当前的网络设置:
  

• Network->Interfaces界面的配置保存在/etc/config/network中。