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Diffstat (limited to 'qemu/roms/u-boot/doc/README.link-local')
| -rw-r--r-- | qemu/roms/u-boot/doc/README.link-local | 75 |
1 files changed, 0 insertions, 75 deletions
diff --git a/qemu/roms/u-boot/doc/README.link-local b/qemu/roms/u-boot/doc/README.link-local deleted file mode 100644 index 9586eca26..000000000 --- a/qemu/roms/u-boot/doc/README.link-local +++ /dev/null @@ -1,75 +0,0 @@ ------------------------------------------- - Link-local IP address auto-configuration ------------------------------------------- - -Negotiate with other link-local clients on the local network -for an address that doesn't require explicit configuration. -This is especially useful if a DHCP server cannot be guaranteed -to exist in all environments that the device must operate. - -This is an implementation of RFC3927. - ----------- - Commands ----------- - -When CONFIG_CMD_LINK_LOCAL is defined in the board config file, -the "linklocal" command is available. This running this will -take approximately 5 seconds while the address is negotiated. - ------------------------- - Environment interation ------------------------- - -The "llipaddr" variable is set with the most recently -negotiated address and is preferred in future negotiations. - -The "ipaddr", "netmask", and "gatewayip" variables are set -after successful negotiation to enable network access. - -------------- - Limitations -------------- - -RFC3927 requires that addresses are continuously checked to -avoid conflicts, however this can only happen when the NetLoop -is getting called. It is possible for a conflict to go undetected -until a command that accesses the network is executed. - -Using NetConsole is one way to ensure that NetLoop is always -processing packets and monitoring for conflicts. - -This is also not a concern if the feature is use to connect -directly to another machine that may not be running a DHCP server. - ----------------- - Example script ----------------- - -This script allows use of DHCP and/or Link-local controlled -by env variables. It depends on CONFIG_CMD_LINK_LOCAL, CONFIG_CMD_DHCP, -and CONFIG_BOOTP_MAY_FAIL. -If both fail or are disabled, static settings are used. - -#define CONFIG_EXTRA_ENV_SETTINGS \ - "ipconfigcmd=if test \\\"$dhcpenabled\\\" -ne 0;" \ - "then " \ - "dhcpfail=0;dhcp || dhcpfail=1;" \ - "else " \ - "dhcpfail=-1;" \ - "fi;" \ - "if test \\\"$linklocalenabled\\\" -ne 0 -a " \ - "\\\"$dhcpfail\\\" -ne 0;" \ - "then " \ - "linklocal;" \ - "llfail=0;" \ - "else " \ - "llfail=-1;" \ - "fi;" \ - "if test \\\"$llfail\\\" -ne 0 -a " \ - "\\\"$dhcpfail\\\" -ne 0; " \ - "then " \ - "setenv ipaddr $sipaddr; " \ - "setenv netmask $snetmask; " \ - "setenv gatewayip $sgatewayip; " \ - "fi;\0" \ |