[Dnsmasq-discuss] iptables configuration drops packets

[Adam Hardy]

Hi,

I set up iptables myself today after using an obtusely written script for some 
time.

I am trying to work out whether everything is in order and I am seeing logs from 
iptables saying that it is dropping packets from the machine every 12 minutes, 
which doesn't make sense - here's a line from the log:

May 16 19:21:10 isengard kernel: dropped from OUTPUT IN= OUT=eth1 
SRC=192.168.0.2 DST=192.168.0.255 LEN=237 TOS=0x00 PREC=0x00 TTL=64 ID=0 DF 
PROTO=UDP SPT=138 DPT=138 LEN=217

The machine is running dhclient3 and dnsmasq and it acts as a gateway, serving 
dhcp to the internal lan on one NIC and forwarding packets to the internet via 
the other NIC (which gets its IP address via DHCP from the DSL modem)  - and 
this is the dhcp3.conf:

ddns-update-style none;
option domain-name "domain01";
option domain-name-servers 194.74.65.69, 217.35.209.180;
default-lease-time 600;
max-lease-time 7200;
authoritative;
log-facility local7;
subnet 192.168.0.0 netmask 255.255.255.0 {
   range 192.168.0.3 192.168.0.254;
   option subnet-mask 255.255.255.0;
   option broadcast-address 192.168.0.255;
   option routers 192.168.0.2;
}

I'm trying to find out what the broadcast address is for and I'm pretty much in 
the dark despite looking around the mailing list and google.

Thanks for any advice,
Adam