Now, RoutesToDNS= and RoutesToNTP= are enabled by default on DHCPv4
client. So, if DHCP server picks up DNS or NTP servers from uplink,
then the routes may break CI environment.
Hopefully fixes#19463.
They are not really boolean, because we have both ipv4 and ipv6, but
for each protocol we have either unset, no, and yes.
From https://github.com/systemd/systemd/issues/13316#issuecomment-582906817:
LinkLocalAddressing must be a boolean option, at least for ipv4:
- LinkLocalAddressing=no => no LL at all.
- LinkLocalAddressing=yes + Static Address => invalid configuration, warn and
interpret as LinkLocalAddressing=no, no LL at all.
(we check that during parsing and reject)
- LinkLocalAddressing=yes + DHCP => LL process should be subordinated to the
DHCP one, an LL address must be acquired at start or after a short N
unsuccessful DHCP attemps, and must not stop DHCP to keeping trying. When a
DHCP address is acquired, drop the LL address. If the DHCP address is lost,
re-adquire a new LL address.
(next patch will move in this direction)
- LinkLocalAddressing=fallback has no reason to exist, because LL address must
always be allocated as a fallback option when using DHCP. Having both DHCP
and LL address at the same time is an RFC violation, so
LinkLocalAdressing=yes correctly implemented is already the "fallback"
behavior. The fallback option must be deprecated and if present in older
configs must be interpreted as LinkLocalAddressing=yes.
(removed)
- And for IPv6, the LinkLocalAddress option has any sense at all? IPv6-LL
address aren't required to be always set for every IPv6 enabled interface (in
this case, coexisting with static or dynamic address if any)? Shouldn't be
always =yes?
(good question)
This effectively reverts 29e81083bd. There is no
special "fallback" mode now, so the check doesn't make sense anymore.
We usually disable IPv6AcceptRA= if the test does not require any
dynamic address configuration, as it makes slightly slow down the test.
C.f. 491b79aeac.
borna-blazevic
Yu Watanabe
Jörg DeckertandJörg Deckert
Yegor Alexeyev
LetzteInstanz
Annika Wickert
Dan Streetman
Zbigniew Jędrzejewski-Szmek