Dear all,
I have a little problem. I have an 3com ISDN router, which broadcasts
every 10 seconds on src-port 1025, dst-port 2071 and protocol udp.
3com has released a program that collects those broadcasts to report the
status of the router.
The log of the packets:
Dec 21 09:46:51 firewall kernel: IN=eth0 OUT=
MAC=ff:ff:ff:ff:ff:ff:08:00:4e:a6:f5:74:08:00 SRC=192.168.1.1
DST=192.168.1.255 LEN=116 TOS=0x00 PREC=0x00 TTL=64 ID=42318 PROTO=UDP
SPT=1025 DPT=2071 LEN=96
Now I want to move my computer behind my firewall and let my firewall to
forward those broadcasts.
The new situations will be:
+----------+ +----------+ +----------+
| ISDN- | | | | ADSL- |
| router |-----| firewall |-----| router |
| | | | | |
+----------+ +----------+ +----------+
|
|
|
+----------+
| Internal |
| network |
| |
+----------+
What I already have done:
I have added the following rule:
iptables -t nat -I PREROUTING -s 192.168.1.1 -p udp --sport 1025 --dport
2071 -j DNAT --to 192.168.2.255
The logging changed:
Dec 21 09:42:01 firewall kernel: IN=eth0 OUT=
MAC=ff:ff:ff:ff:ff:ff:08:00:4e:a6:f5:74:08:00 SRC=192.168.1.1
DST=192.168.2.255 LEN=116 TOS=0x00 PREC=0x00 TTL=64 ID=42284 PROTO=UDP
SPT=1025 DPT=2071 LEN=96
But no packets went out, at least that I couldn't see after adding a
LOG-rule at OUTPUT and FORWARD.
Is there an easy way to solve this or do I need a relaying-program (like
dhcp)?
Greetings,
--
Frans Luteijn
PGP PblKey fprnt=C4 87 CE AF BC B6 98 C1 EF 42 A1 9A E2 C0 42 5B
GPG PblKey fprnt=ED20 0F25 C233 DC59 3FFA 170E D0BF 15F5 0BA6 1355
