On Fri, 11 Mar 2011 11:15:36 PST, ann kok said:
inet6 addr: fe80::20c:29ff:fe3c:92a1/64 Scope:Link
This is a link level address, only valid on one interface. So you need to look at which interface it is attached to in the ifconfig output.
ping6 fe80::20c:29ff:fe3c:92a1 connect: Invalid argument
ping6 wants the interface name for link-scope addresses, because on some hardware setups, the same MAC is used for all interfaces, which means that each interface has the same link-scope address. So to disambiguate it, you have to feed it the interface name so it knows which link to use. On my laptop, I currently have: wlan0 Link encap:Ethernet HWaddr 00:24:D6:53:C5:BA inet6 addr: fe80::224:d6ff:fe53:c5ba/64 Scope:Link % ping fe80::224:d6ff:fe53:c5ba%wlan0 ping6 fe80::224:d6ff:fe53:c5ba%wlan0 PING fe80::224:d6ff:fe53:c5ba%wlan0(fe80::224:d6ff:fe53:c5ba) 56 data bytes 64 bytes from fe80::224:d6ff:fe53:c5ba: icmp_seq=1 ttl=64 time=0.072 ms 64 bytes from fe80::224:d6ff:fe53:c5ba: icmp_seq=2 ttl=255 time=0.081 ms 64 bytes from fe80::224:d6ff:fe53:c5ba: icmp_seq=3 ttl=255 time=0.090 ms ^C --- fe80::224:d6ff:fe53:c5ba%wlan0 ping statistics --- 3 packets transmitted, 3 received, 0% packet loss, time 1999ms rtt min/avg/max/mdev = 0.072/0.081/0.090/0.007 ms