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

• Login via Serial Port

When you do kernel development you'd better get a serial communication board. After you connect your board to a serial communication board you will be able to do development work from a commandline utility.
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 Check System Status

• Check CPU Temperature & Frequency via Commandline

$ 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

These messages mean that there are four CPU cores working online simultaneously. Each core's temperature is 26.5 degrees in Celsius, the scheduling policy is on-demand and the working frequency is 624MHz. You can set the frequency by running the following command:

$ 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.

• Check System Status on OpenWrt-LuCI Web Page

After open the OpenWrt-LuCI page, go to "Statistics ---> Graphs" and you will see various system statistics e.g.:
1) System Load:

2) RAM:

3) CPU Temperature:

All the statistics listed on the Statistics page are presented by the luci-app-statistics package which uses the Collectd utility to collect data and presents them with the RRDtool utility.
If you want to get more statistics you can install other collectd-mod-* packages. 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 Check Network->Interfaces Configurations

• After open the OpenWrt-LuCI page, go to "Network" ---> "Interfaces" and you will see the current network's configurations:
  

• All the configurations listed on the Network->Interfaces page are stored in the "/etc/config/network" file.