ipv6 question

[ann kok <oiyankok () yahoo ca>]

Hi

I read ipv6forum.pdf about ipv6

It said 

MTU must be at least 1280 bytes (1500+)
Does it mean to set the mtu over 1500

I set my linux box eth0 as 2001:db8:cafe:1111::12/64 but I can't ping it
inet6 2001:db8:cafe:1111::12/64 scope global tentative 

ls it this problem? Thank you


# ping6 2001:db8:cafe:1111::12
PING 2001:db8:cafe:1111::12(2001:db8:cafe:1111::12) 56
      

data bytes
    

> From ::1 icmp_seq=1 Destination unreachable:
      

Address unreachable
    

> From ::1 icmp_seq=2 Destination unreachable:
      

Address unreachable