[syslinux] pxelinux magic options 208

[Daniel Feenberg]

Solution found.

Although pxelinux will look for the hexadecimally named config files in 
the directory /tftpboot/pxelinux.cfg by default, and will eventually load 
"default" from that same directory if no more specific configuration is 
found, the filename in a pxelinux.configfile statement is relative 
/tftpboot alone - the subdirectory must be specified as part of the 
filename. This is stated in a line in the wiki:

>  Note that all filename references are relative to the directory
>  pxelinux.0 lives in.


The import of that line did not register on me. Given the distance between 
this line and the section on configuring dhcpd I assumed that this 
referred to the filenames in the pxelinux configuration files, not the 
dhcpd.conf. The configuration was fixed by using:

   option pxelinux.configfile "pxelinux.cfg/bsddefault";

in the dhcpd.conf The working configuration uses the vendor option and 
omits the magic option:

=============================================
option space pxelinux;
option pxelinux.configfile code 209 = text;
vendor-option-space pxelinux;
...

group {
    next-server 66.251.72.1;
    filename "pxelinux384.0";
    option root-path "66.251.72.44:/vol/vol1c/FreeBSD-8.1-root";
    if exists dhcp-parameter-request-list {option dhcp-parameter-request-list =
       concat(option dhcp-parameter-request-list,d0,d1,d2,d3);}
    option pxelinux.configfile "pxelinux.cfg/bsddefault";
    host client2 {fixed-address 66.251.73.20;hardware ethernet 0:13:20:4c:7d:08;}
}

============================================

At the end of the wiki is a block entitled "Directory Structure". It might 
be helpful to new users if examples reflected that directory structure.

Daniel Feenberg
NBER