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Diffstat (limited to 'doc/usage/netconsole.rst')
| -rw-r--r-- | doc/usage/netconsole.rst | 55 |
1 files changed, 45 insertions, 10 deletions
diff --git a/doc/usage/netconsole.rst b/doc/usage/netconsole.rst index 2aa3b9ccc59..df27b78342f 100644 --- a/doc/usage/netconsole.rst +++ b/doc/usage/netconsole.rst @@ -3,10 +3,10 @@ Network console In U-Boot, we implemented the networked console via the standard "devices" mechanism, which means that you can switch between the -serial and network input/output devices by adjusting the 'stdin' and -'stdout' environment variables. To switch to the networked console, -set either of these variables to "nc". Input and output can be -switched independently. +serial and network input/output devices by adjusting the 'stdin', +'stdout', and 'stderr' environment variables. To switch to the +networked console, set either of these variables to "nc". Input and +output can be switched independently. The default buffer size can be overridden by setting CFG_NETCONSOLE_BUFFER_SIZE. @@ -18,14 +18,18 @@ broadcast address and port 6666 are used. If it is set to an IP address of 0 (or 0.0.0.0) then no messages are sent to the network. The source / listening port can be configured separately by setting the 'ncinport' environment variable and the destination port can be -configured by setting the 'ncoutport' environment variable. +configured by setting the 'ncoutport' environment variable. Note that +you need to set up the network interface (e.g. using DHCP) before it +can be used for network console. -For example, if your server IP is 192.168.1.1, you could use:: +For example, if your server IP is 192.168.1.1, you could use: - => setenv nc 'setenv stdout nc;setenv stdin nc' - => setenv ncip 192.168.1.1 - => saveenv - => run nc +.. prompt:: bash => + + env set nc 'env set stdout nc; env set stderr nc; env set stdin nc' + env set ncip '192.168.1.1' + env save + run nc On the host side, please use this script to access the console @@ -107,3 +111,34 @@ as follows: Note that unlike the U-Boot implementation the Linux netconsole is unidirectional, i. e. you have console output only in Linux. + +Setup via environment +--------------------- + +If persistent environment is enabled in your U-Boot configuration, you +can configure the network console using the environment. For example: + +.. prompt:: bash => + + env set autoload no + env set hostname "u-boot" + env set bootdelay 5 + env set nc 'dhcp; env set stdout nc; env set stderr nc; env set stdin nc' + env set ncip '192.168.1.1' + env set preboot "${preboot}; run nc;" + env save + reset + +``autoload no`` tells the ``dhcp`` command to configure the network +interface without trying to load an image. ``hostname "u-boot"`` sets +the hostname to be sent in DHCP requests, so they are easy to +recognize in the DHCP server log. The command in ``nc`` calls ``dhcp`` +to make sure the network interface is set up before enabling +netconsole. + +Adding ``nc`` to ``preboot`` tells U-Boot to activate netconsole +before trying to find any boot options, so you can interact with it if +desired. + +``env save`` stores the settings persistently, and ``reset`` then +triggers a fresh start that will use the changed settings. |