Border-router and multicast

Development archive
21

Thanks Martine, I will try tomorrow

Hi,

Ah the problem seems to be that for some reason Linux elects a link-local address for the ping, which is of course due to the fact, that there is no global address assigned to the interface and that the hop limit seems to be set to short (it is 1). So I did the following

sudo ip route add ff1e::/16 dev tap0 table local # add routing entry for ff1e::1 sudo ip addr add affe::dc53:7dff:fe99:516e/64 dev tap0 # add global unicast address for tap0 ping6 -t 2 ff1e::1 # ping with hop limit 2

I did try but ping6 does not receive anything Did you do any more set up? What is this address dc53:7dff:fe99:516e?

#ip -6 route list table local ... ff1e::/16 dev tap0 metric 1024 ...

#ifconfig tap0 tap0 Link encap:Ethernet HWaddr 26:C5:07:2F:43:E0           inet6 addr: fe80::24c5:7ff:fe2f:43e0/64 Scope:Link           inet6 addr: fe80::1/64 Scope:Link           inet6 addr: affe::dc53:7dff:fe99:516e/64 Scope:Global           UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1           RX packets:58 errors:0 dropped:0 overruns:0 frame:0           TX packets:326 errors:0 dropped:0 overruns:0 carrier:0           collisions:0 txqueuelen:500           RX bytes:4706 (4.5 KiB) TX bytes:29442 (28.7 KiB)

22

Martine?

23

Hi,

Sorry forgot to answer this.

I did try but ping6 does not receive anything Did you do any more set up?

As I said: I wasn’t able to reach the multicast address either (at least after the first reply + the reply didn’t seem to be forwarded by the BR [something I seem to have forgotton to mention; I just saw it with my sniffer]), so further investigation needs to be done (e.g. using ENABLE_DEBUG in gnrc_ipv6.c or with gdb).

What is this address dc53:7dff:fe99:516e?

That’s the IID of the tap0 interface in my configation at the time (It’s the same as you link-local address has after the fe80:: part and is usually derived from the interface’s MAC address). But that could have been basically anything.

Cheers, Martine