I have a very basic Ubuntu 20.04 server installation.
I am trying to disable the system from using temporary IPv6 addresses.
My netplan is as follows:
network:
ethernets:
ens160:
addresses:
- 192.168.1.10/24
- "2605:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx/64"
gateway4: 192.168.1.1
gateway6: "2605:xxxx:xxxx:xxxx::1"
accept-ra: no
ipv6-privacy: off
nameservers:
addresses:
- "2605:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx"
- 192.168.1.10
version: 2
This is the only file in the /etc/netplan/ directory.
I also disabled use_tempaddr with sysctl:
sudo sysctl -a | grep use_tempaddr
[sudo] password for xxxxxx:
net.ipv6.conf.all.use_tempaddr = 0
net.ipv6.conf.default.use_tempaddr = 0
net.ipv6.conf.ens160.use_tempaddr = 0
net.ipv6.conf.lo.use_tempaddr = -1
Notice that the changes are written to the files, so they persist.
I then do an sudo ip addr flush, reboot, but every time there's a 2nd IPv6 address with is dynamic mngtmpaddr noprefixroute.
...
inet6 2605:xxxx:xxxx:yyyy:yyyy:yyyy:yyyy:yyyy/64 scope global dynamic mngtmpaddr noprefixroute
valid_lft 43183sec preferred_lft 43183sec
inet6 2605:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx/64 scope global
valid_lft forever preferred_lft forever
...
How can I avoid that one from being created?