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I have 2 linux box configured with IPv4. I have tried adding IPv6 to them. I have issued this commands on box1:

ip -6 addr add fd32:2d7f:f3c1::1/48 dev eth0

And I get this:

inet6 addr: fd32:2d7f:f3c1::1/48 Scope:Global

Then I have issued this command on box2:

ip -6 addr add fd32:2d7f:f3c2::1/48 dev eth0

Back on box1 (command/response):

ping6 fd32:2d7f:f3c1::1
 is alive!
ping6 fd32:2d7f:f3c2::1
ping6: sendto: Network is unreachable

Why doesn't box1 ping box2 (of course, also box2 can't ping box1)?

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How are they connected to each other. Can you explain the network setup. – Manula Waidyanatha Sep 10 '12 at 9:28
With a cross-cable. – michelemarcon Sep 10 '12 at 9:41
up vote 5 down vote accepted

Look at your prefix, you are not on the same network.

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In addition: it is strongly recommended to use a /64 on a LAN. Other sizes will (probably) work, but you'll lose some functionality like SLAAC if you do. And using a /48 on a point-to-point link is a huge waste of addresses. Not that there is an address shortage, but there is no reason to use 65536 times as much addresses as the already virtually unlimited amount that a /64 provides. – Sander Steffann Sep 10 '12 at 13:26

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