It can be useful to choose a different "ipv6.addr-gen-mode". And it can be
useful to override the default for a set of profiles.
For example, in cloud or in a data center, stable-privacy might not be
the best choice. Add a mechanism to override the default via global defaults
in NetworkManager.conf:
# /etc/NetworkManager/conf.d/90-ipv6-addr-gen-mode-override.conf
[connection-90-ipv6-addr-gen-mode-override]
match-device=type:ethernet
ipv6.addr-gen-mode=0
"ipv6.addr-gen-mode" is a special property, because its default depends on
the component that configures the profile.
- when read from disk (keyfile and ifcfg-rh), a missing addr-gen-mode
key means to default to "eui64".
- when configured via D-Bus, a missing addr-gen-mode property means to
default to "stable-privacy".
- libnm's ip6-config::addr-gen-mode property defaults to
"stable-privacy".
- when some tool creates a profile, they either can explicitly
set the mode, or they get the default of the underlying mechanisms
above.
- nm-initrd-generator explicitly sets "eui64" for profiles it creates.
- nmcli doesn' explicitly set it, but inherits the default form
libnm's ip6-config::addr-gen-mode.
- when NM creates a auto-default-connection for ethernet ("Wired connection 1"),
it inherits the default from libnm's ip6-config::addr-gen-mode.
Global connection defaults only take effect when the per-profile
value is set to a special default/unset value. To account for the
different cases above, we add two such special values: "default" and
"default-or-eui64". That's something we didn't do before, but it seams
useful and easy to understand.
Also, this neatly expresses the current behaviors we already have. E.g.
if you don't specify the "addr-gen-mode" in a keyfile, "default-or-eui64"
is a pretty clear thing.
Note that usually we cannot change default values, in particular not for
libnm's properties. That is because we don't serialize the default
values to D-Bus/keyfile, so if we change the default, we change
behavior. Here we change from "stable-privacy" to "default" and
from "eui64" to "default-or-eui64". That means, the user only experiences
a change in behavior, if they have a ".conf" file that overrides the default.
https://bugzilla.redhat.com/show_bug.cgi?id=1743161https://bugzilla.redhat.com/show_bug.cgi?id=2082682
See-also: https://github.com/coreos/fedora-coreos-tracker/issues/907https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1213
This test calls "nmcli g" with a bogus D-Bus bus address. We expect
a failure on stderr.
On alpine:latest, the error however looks slightly different:
b'size: 258\nlocation: src/tests/client/test-client.py:test_offline()/1\ncmd: $NMCLI g\nlang: C\nreturncode: 1\nstderr: 136 bytes\n>>>\nError: Could not create NMClient object: Key/Value pair 0, *invalid*, in address element *very:invalid* does not contain an equal sign.\n\n<<<\n'
On ubuntu:16.04 and debian:9 we got:
b"size: 258\nlocation: src/tests/client/test-client.py:test_offline()/1\ncmd: $NMCLI g\nlang: C\nreturncode: 1\nstderr: 136 bytes\n>>>\nError: Could not create NMClient object: Key/Value pair 0, 'invalid', in address element 'very:invalid' does not contain an equal sign.\n\n<<<\n"
On fedora and most recent systemd we got:
b'size: 258\nlocation: src/tests/client/test-client.py:test_offline()/1\ncmd: $NMCLI g\nlang: C\nreturncode: 1\nstderr: 136 bytes\n>>>\nError: Could not create NMClient object: Key/Value pair 0, ?invalid?, in address element ?very:invalid? does not contain an equal sign.\n\n<<<\n'
This depends on the glib version (whether to print `%s', '%s', or “%s”).
Also, as we run the application with lang=C, so that libc (I think)
replaces Unicode with an ASCII character. Here musl and glibc behave
differently.
Workaround by replace the unexpected text.
