Alex Berdan wrote:
Hi All,
I set up a GRE tunnel between two sites to have the
broadcast/multicast passing between the two but nothing is passing!
I'm not using for the moment any firewall and the configuration
straight forward as per man gre.
192.168.1.2/24
|
|
|
--------|----------
192.168.1.1/24
Gateway A
10.0.0.1/24
--------|-----------
|
internet
|
--------|-----------
172.16.2.2
Gateway B
192.168.3.1/24
--------|----------
|
|
|
192.168.3.2/24
On Gateway A I have:
ifconfig gre0 create
ifconfig gre0 192.168.1.1 192.168.3.1 netmask 255.255.255.255 link1 up
ifconfig gre0 tunnel 10.0.0.1 172.16.2.2
For the Gateway B I have:
ifconfig gre0 create
ifconfig gre0 192.168.3.1 192.168.1.1 netmask 255.255.255.255 link1 up
ifconfig gre0 tunnel 172.16.2.2 10.0.0.1
The Windows broadcast that I have behind 192.168.1.0/24 is not passing
through the GRE tunnel which is UP and running. Also the OSPF which is
multicasting is not passing through the gre0 interface. Pinging the
internal interfaces in both sites is working. Tcpdump on the gre0
interface is not showing anything.
Could you please can you give me any clue on how should I debug?
Alex
You have different logical networks on either side of the tunnel, which
means routing is involved. Broadcasts do not cross network routers by
default, which prevents everyone's broadcasts from crossing the entire
Internet (a good thing).
