On 22/02/2017 22:41, Alexandre Petrescu wrote:
<snip>
>> Well that does two things: configures a 128 bit address (as Chris
>> points out, *all* addresses are 128 bits, duh) and associates a
>> prefix length with it, which afaik is optional.
>
> The prefix length is not optional. There is no system out there on
> which one could configure a 128bit address without explicitely telling
> '/128' or '/64' or '/something-else'.
Wrong. Sorry to get all technical, but on Windows:
C:\windows\system32>netsh interface ipv6 add address ?
Usage: add address [interface=]<string> [address=]<IPv6 address>[/<integer>]
[[type=]unicast|anycast]
[[validlifetime=]<integer>|infinite]
[[preferredlifetime=]<integer>|infinite]
[[store=]active|persistent]
[[skipassource=]true|false]
The [/<integer>] looks pretty optional to me. I just tried
netsh interface ipv6 add address 12 2001:db8:dead::beef
and now I have three addresses:
C:\windows\system32>netsh interface ipv6 show addresses
Interface 12: Wireless Network Connection
Addr Type DAD State Valid Life Pref. Life Address
--------- ----------- ---------- ---------- ------------------------
Manual Preferred infinite infinite 2001:db8:dead::beef
Public Preferred 1h54m9s 54m9s fd63:45eb:dc14:0:28cc:dc4c:9703:6781
Other Preferred infinite infinite fe80::28cc:dc4c:9703:6781%12
When I try to ping 2001:db8:dead::cafe, I see what I expected in Wireshark:
neighbour solicitations from 2001:db8:dead::beef to ff02::1:ff00:cafe.
In other words, the new address is treated as on-link. I can't find any trace
of an associated prefix entry.
Maybe Linux is different.
Brian