IPV6 addresses

Colin Law clanlaw at gmail.com
Mon Jun 25 12:29:48 UTC 2018


On 25 June 2018 at 11:34, Karl Auer <kauer at biplane.com.au> wrote:
> On Mon, 2018-06-25 at 11:09 +0100, Colin Law wrote:
>> On another machine with a fresh install, however, the fe80:: address
>> does not have any obvious relationship to the MAC address and has not
>> got ff:fe at the appropriate place. I deduce from this that there
>> other allowed techniques for generating the address but I can't find
>> any reference to them anywhere.  Can anyone elucidate?
>
> Not sure where they would be documented, but check out the
> configuration options in /proc/sys/net/ipv6/conf/all/ and compare them
> with the options available on the other system.

I thought that was it, /proc/sys/net/ipv6/conf/all/addr_gen_mode [1]
and [2] which seems to fit the bill exactly. Unfortunately it is set
to 0 on both systems, so there must be something else.

Colin

[1] https://developer.gnome.org/NetworkManager/stable/settings-ipv6.html
[2] https://tools.ietf.org/html/rfc7217



More information about the ubuntu-users mailing list