[syslinux] pxelinux aborts booting

[Christian Hoefer]

Hi,
i try booting a PXE equipped client with pxelinux.

The problem is: after receiving the file pxelinux.0 it requests
pxelinux.cfg/C0A86451 and aborts.
tcpdump:
....
16:01:58.786946 192.168.100.81.2073 > saturn.1337:  udp 4
16:01:58.787033 saturn.1337 > 192.168.100.81.2073:  udp 516 (DF)
16:01:58.787202 192.168.100.81.2073 > saturn.1337:  udp 4
16:01:58.787528 saturn.1337 > 192.168.100.81.2073:  udp 516 (DF)
16:01:58.787703 192.168.100.81.2073 > saturn.1337:  udp 4
16:01:58.787793 saturn.1337 > 192.168.100.81.2073:  udp 348 (DF)
16:01:58.787932 192.168.100.81.2073 > saturn.1337:  udp 4
16:01:58.827477 192.168.100.81.57217 > saturn.tftp:  52 RRQ
"/var/tftpboot/pxelinux.cfg/C0A86451"
16:02:03.755659 saturn.1336 > 192.168.100.81.2072:  udp 516 (DF)
16:02:08.755776 saturn.1336 > 192.168.100.81.2072:  udp 516 (DF)
16:02:08.860782 saturn.1337 > 192.168.100.81.57217:  udp 216 (DF)
16:02:08.860914 192.168.100.81.57217 > saturn.1337:  udp 26

at this point the client resets. 192.168.100.81 is the client, saturn
is the dhcp/tftp server.

The syslinux docu says:

+ The error recovery routine doesn't work quite right.  For right
 now, it just does a hard reset - seems good enough.

and that's exactly what it does. And i have no chance to know why.
/var/tftpboot/pxelinux.cfg/C0A86451 exists and is readable to tftpd.
I'm allmost 100% sure it is syntactically correct. But from tcpdump i
see it is never loaded (and parsed).

any hint is more than welcome,
Christian