Arch Linux

vanillamilkk

Member

Registered: 2021-03-11

Posts: 14

how do i get multiple ipv6 with systemd-networkd

on android devices usually you will get 4 or more ipv6 addresses (link local and 3 global addressable)
one of them is for listening incoming connection from the internet (usually generated from interface's mac)
and the last two generated randomly which also used randomly for making a connection to outside internet (i think for privacy reason?)

but my arch install with systemd-networkd only have two addresses, link local and single globally unique address with my isp prefix and my interface mac

-thc

Member

Registered: 2017-03-15

Posts: 775

Re: how do i get multiple ipv6 with systemd-networkd

on android devices usually you will get 4 or more ipv6 addresses (link local and 3 global addressable)
one of them is for listening incoming connection from the internet (usually generated from interface's mac)
and the last two generated randomly which also used randomly for making a connection to outside internet (i think for privacy reason?)

The default for (my) Android 11 is two interface ids. One generated via EUI64 (from the MAC address) and a temporary one. Those two combined with a public network prefix (2000::/3) should lead to 3 IPv6 addresses:

fe80::EUI64
public:EUI64
public:temporary

I'm not sure where your fourth address comes from - it may be a deprecated temporary address (they're usually valid for an hour or so).

but my arch install with systemd-networkd only have two addresses, link local and single globally unique address with my isp prefix and my interface mac

This is the default for systemd-networkd:

fe80::EUI64
public:EUI64

So - do you want a temporary address for outgoing connections? Or do you want a different interface ID via "privacy stable" for both directions?

EdeWolf

Member

Registered: 2016-01-06

Posts: 85

Re: how do i get multiple ipv6 with systemd-networkd

You add "IPv6PrivacyExtensions=true" to the [Network] block for your interface .network file below /etc/systemd/network