{manpage} already exapnds to a link but akkoma wants to link to
a specific setting. split the mention for clarity.
networkd just straight up duplicated what {manpage} generates anyway, so
that link can go away completely.
When no interfaces are managed by systemd-networkd, it will
unconditionally fail. This option allows it to be disabled in those
situations where it prevents system switches from succeeding.
Systemd 250:
> DHCPv4 client support in systemd-networkd learnt a new Label= option
> for configuring the address label to apply to configure IPv4
> addresses.
> The [IPv6AcceptRA] section of .network files gained support for a new
> UseMTU= setting that may be used to control whether to apply the
> announced MTU settings to the local interface.
> The [DHCPv4] section in .network file gained a new Use6RD= boolean
> setting to control whether the DHCPv4 client request and process the
> DHCP 6RD option.
> The [DHCPv6] section in .network file gained a new setting
> UseDelegatedPrefix= to control whether the delegated prefixes will be
> propagated to the downstream interfaces.
> The [IPv6AcceptRA] section of .network files now understands two new
> settings UseGateway=/UseRoutePrefix= for explicitly configuring
> whether to use the relevant fields from the IPv6 Router Advertisement
> records.
> The [RoutingPolicyRule] section of .network file gained a new
> SuppressInterfaceGroup= setting.
> The IgnoreCarrierLoss= setting in the [Network] section of .network
> files now allows a duration to be specified, controlling how long to
> wait before reacting to carrier loss.
Systemd 246:
> systemd-networkd's [DHCPv4] section gained a new setting UseGateway=
> which may be used to turn off use of the gateway information provided
> by the DHCP lease. A new FallbackLeaseLifetimeSec= setting may be
> used to configure how to process leases that lack a lifetime option.
> The IPv6Token= section in the [Network] section is deprecated, and
>> the [IPv6AcceptRA] section gained the Token= setting for its
>> replacement. The [IPv6Prefix] section also gained the Token= setting.
>> The Token= setting gained 'eui64' mode to explicitly configure an
>> address with the EUI64 algorithm based on the interface MAC address.
>> The 'prefixstable' mode can now optionally take a secret key. The
>> Token= setting in the [DHCPPrefixDelegation] section now supports all
>> algorithms supported by the same settings in the other sections.
* Remove `ForceDHCPv6PDOtherInformation=`
* Add a missing `WithoutRA=` option
Systemd 250:
> The ForceDHCPv6PDOtherInformation= setting in the [DHCPv6] section
> has been removed. Please use the WithoutRA= and UseDelegatedPrefix=
> settings in the [DHCPv6] section and the DHCPv6Client= setting in the
> [IPv6AcceptRA] section to control when the DHCPv6 client is started
> and how the delegated prefixes are handled by the DHCPv6 client.
Adapt to changes introduced in Systemd 250:
> The [DHCPv6PrefixDelegation] section in .network file is renamed to
> [DHCPPrefixDelegation], as now the prefix delegation is also
> supported with DHCPv4 protocol by enabling the Use6RD= setting.
Replaces the `dhcpV6PrefixDelegationConfig` with
`dhcpPrefixDelegationConfig` and throws an error if the old option is
used.
Also adapt the respective IPv6 prefix delegation test.
