Joakim Tjernlund wrote on 11/02/2020 19:27: > On Tue, 2020-02-11 at 18:18 +0100, Alarig Le Lay wrote: >> On mar. 11 févr. 17:52:29 2020, Bastien Durel wrote: >>> 7: wg4b: <POINTOPOINT,NOARP,UP,LOWER_UP> mtu 1420 state UNKNOWN qlen 1000 >>> inet6 fe80::3/128 scope link >>> valid_lft forever preferred_lft forever >>> 8: wg4a: <POINTOPOINT,NOARP,UP,LOWER_UP> mtu 1420 state UNKNOWN qlen 1000 >>> inet6 fe80::3/128 scope link >>> valid_lft forever preferred_lft forever >> >> Don’t put fe80 addresses by hand and definitely not with /128, let your >> kernel handles this. > > I always wondered why not /128 ? In IPV4 they are just fine.
Because IPv6 Link-Local *IS* using a /64 prefix. [0] \-> rfc4291, Sec. 2.5.6 [1] If you assign link local addresses with any other mask length than 64. You cannot assume the software will behave as you expect. Because using < 64 > is outside the scope of how the link local addresses are defined in the RFC. Chriztoffer [0]: https://packetlife.net/blog/2011/apr/28/ipv6-link-local-addresses/ [1]: https://tools.ietf.org/html/rfc4291#section-2.5.6
