I found this bug report because I have the same issue, but I think it's because the interface is "UP". When I try the same "set" command on a "DOWN" interface, it's successful. My issue is figuring out how to run the set command during the boot process on the eth0 interface, before it comes up. Netplan is making this difficult.
ubuntu@ubuntu:/etc/networkd-dispatcher/degraded.d$ sudo ip token list token :: dev eth0 token :: dev wlan0 ubuntu@ubuntu:/etc/networkd-dispatcher/degraded.d$ sudo ip token set ::18/64 dev eth0 RTNETLINK answers: Invalid argument ubuntu@ubuntu:/etc/networkd-dispatcher/degraded.d$ sudo ip token set ::18/64 dev wlan0 ubuntu@ubuntu:/etc/networkd-dispatcher/degraded.d$ ip addr 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000 link/ether dc:a6:32:37:a0:3a brd ff:ff:ff:ff:ff:ff inet xxx.xxx.xxx.125/24 brd 192.168.88.255 scope global dynamic eth0 valid_lft 604343sec preferred_lft 604343sec inet6 <HIDDEN VALID IPv6 ADDRESS HERE>/64 scope global dynamic mngtmpaddr noprefixroute valid_lft 345288sec preferred_lft 345288sec inet6 fe80::dea6:32ff:fe37:a03a/64 scope link valid_lft forever preferred_lft forever 3: wlan0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000 link/ether dc:a6:32:37:a0:3b brd ff:ff:ff:ff:ff:ff ubuntu@ubuntu:/etc/networkd-dispatcher/degraded.d$ ip token list token :: dev eth0 token ::18 dev wlan0 -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to iproute2 in Ubuntu. Matching subscriptions: iproute2 https://bugs.launchpad.net/bugs/1777010 Title: ip token set, results in: Invalid argument Status in iproute2 package in Ubuntu: Confirmed Bug description: Hi, I can't set any ipv6 token with ip command. It seems that it has a bug. Also it is not possible to set it with netplan (see bug #1737976) ~# ip token list token :: dev enp1s0 token :: dev enp2s0 token :: dev ovpn0 token :: dev br0 ~# ip token set ::2a:2a:2a:2a/64 dev br0 RTNETLINK answers: Invalid argument ~# ip token set ::2a/64 dev br0 RTNETLINK answers: Invalid argument ~# ip token set ::beef dev br0 RTNETLINK answers: Invalid argument It seems, that this Bug is really old?! https://bbs.archlinux.org/viewtopic.php?id=202757 This is really fatal, because I cant set a static ip. My prefix get mixed from my provider every x days. ProblemType: Bug DistroRelease: Ubuntu 18.04 Package: iproute2 4.15.0-2ubuntu1 ProcVersionSignature: Ubuntu 4.15.0-23.25-generic 4.15.18 Uname: Linux 4.15.0-23-generic x86_64 ApportVersion: 2.20.9-0ubuntu7.2 Architecture: amd64 Date: Fri Jun 15 01:26:04 2018 InstallationDate: Installed on 2018-06-12 (2 days ago) InstallationMedia: Ubuntu-Server 18.04 LTS "Bionic Beaver" - Release amd64 (20180426) ProcEnviron: TERM=xterm PATH=(custom, no user) LANG=de_DE.UTF-8 SHELL=/bin/bash SourcePackage: iproute2 UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/iproute2/+bug/1777010/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp