The setting is completely meaningless, as WithoutRA= and UseDelegatedPrefix=
in [DHCPv6] section, and DHCPv6Client= in [IPv6AcceptRA] section control
the behavior.
Previously, the prefix delegation is enabled when at least one
downstream interfaces request it. But, when the DHCPv6 client on the
upstream interface is configured, some downstream interfaces may not
exist yet, nor have .network file assigned.
Also, if a system has thousands of interfaces, then the previous logic
introduce O(n^2) search.
This makes the prefix delegation is always enabled, except when it is
explicitly disabled. Hopefully, that should not break anything, as the
DHCPv6 server should ignore the prefix delegation request if the server
do not have any prefix to delegate.
When Assign= in [DHCPv6PrefixDelegation] is enabled, then the kernel
will create the prefix route for the assigned address with metric 256.
When Assign= is disabled, then the kernel will create the route with
metric 1024.
For the default value, we should choose a smaller value (higher priority)
than 1024, as the unreachable routes for delegated prefix will be
configured with 1024.
Previously, when Priority= is unspecified, networkd configured the rule with
the highest (=0) priority. This commit makes networkd distinguish the case
the setting is unspecified and one explicitly specified as Priority=0.
Note.
1) If the priority is unspecified on configure, then kernel dynamically picks
a priority for the rule.
2) The new behavior is consistent with 'ip rule' command.
Replaces #15606.
Note that this slightly breaks backward compatibility when
Termination=1. Previously, this is handled as boolean true, then 120 ohm
was used. But now with this commit, it is handled as 1 ohm.
If ActivationPolicy= is set to down, always-down, or manual, then any
matching link will delay boot (due to delaying network-online.target).
If RequiredForOnline= wasn't explicitly set, then default it to false
if ActivationPolicy= is down or manual. If ActivationPolicy=always-down,
then force RequiredForOnline=no.
Previously, IPv6LinkLocalAddressGenerationMode= is not set, then we
define the address generation mode based on the result of reading
stable_secret sysctl value. This makes the mode is determined by whether
a secret address is specified in the new setting.
Closes#19622.
Previously, when a link has already in a numbered group, we cannot
remove the link from the group.
This also fixes the range mentioned in the man page.
Yu Watanabe
Tom Yan
Maxime de Roucy
Zbigniew Jędrzejewski-Szmek
Raul Tambre
Carl Lei
Dan Streetman
borna-blazevic
Lennart Poettering