This changes the UseDomains= setting of .network files to take an optional third value "route", in addition to the
boolean values. If set, the passed domain information is used for routing rules only, but not for the search path
logic.
Previously, .network files only knew a vaguely defined "Domains=" concept, for which the documentation declared it was
the "DNS domain" for the network connection, without specifying what that means.
With this the Domains setting is reworked, so that there are now "routing" domains and "search" domains. The former are
to be used by resolved to route DNS request to specific network interfaces, the latter is to be used for searching
single-label hostnames with (in addition to being used for routing). Both settings are configured in the "Domains="
setting. Normal domain names listed in it are now considered search domains (for compatibility with existing setups),
while those prefixed with "~" are considered routing domains only. To route all lookups to a specific interface the
routing domain "." may be used, referring to the root domain. An alternative syntax for this is the "*", as was already
implemented before using the "wildcard" domain concept.
This commit adds proper parsers for this new logic, and exposes this via the sd-network API. This information is not
used by resolved yet, this will be added in a later commit.
As it turns out the kernel does not support per-interface IPv6 packet
forwarding controls (unlike as it does for IPv4), but only supports a
global option (#1597). Also, the current per-interface management of the
setting isn't really useful, as you want it to propagate to at least one
more interface than the one you configure it on. This created much grief
(#1411, #1808).
Hence, let's roll this logic back and simplify this again, so that we
can expose the same behaviour on IPv4 and IPv6 and things start to work
automatically again for most folks: if a network with this setting set
is set up we propagate the setting into the global setting, but this is
strictly one-way: we never reset it again, and we do nothing for network
interfaces where this setting is not enabled.
Fixes: #1808, #1597.
The previous behavior:
When DHCPv6 was enabled, router discover was performed first, and then DHCPv6 was
enabled only if the relevant flags were passed in the Router Advertisement message.
Moreover, router discovery was performed even if AcceptRouterAdvertisements=false,
moreover, even if router advertisements were accepted (by the kernel) the flags
indicating that DHCPv6 should be performed were ignored.
New behavior:
If RouterAdvertisements are accepted, and either no routers are found, or an
advertisement is received indicating DHCPv6 should be performed, the DHCPv6
client is started. Moreover, the DHCP option now truly enables the DHCPv6
client regardless of router discovery (though it will probably not be
very useful to get a lease withotu any routes, this seems the more consistent
approach).
The recommended default setting should be to set DHCP=ipv4 and to leave
IPv6AcceptRouterAdvertisements unset.
The constraints we place on the pool is that it is a contiguous
sequence of addresses in the same subnet as the server address, not
including the subnet nor broadcast addresses, but possibly including
the server address itself. If the server address is included in the
pool it is (obviously) reserved and not handed out to clients.
This should clear up some confusion in
https://github.com/systemd/systemd/issues/717.
This basically copies the description from systemd.unit to this
man page. Masking can happen also in /run, so strike the part
about /etc, and also add the magic work "mask".
Justification is similar to BPDUGuard rename. "Positive" values
are easier. This is a rather uncommon option, so using a slightly
longer name should not be a problem, and may in fact may make it
easier to guess what the option does without reading the
documentation.
Looking at the kernel commit, "on" seems to be the default value:
commit 867a59436fc35593ae0e0efcd56cc6d2f8506586
Author: Vlad Yasevich <vyasevic@redhat.com>
Date: Wed Jun 5 10:08:01 2013 -0400
bridge: Add a flag to control unicast packet flood.
Add a flag to control flood of unicast traffic. By default, flood is
on and the bridge will flood unicast traffic if it doesn't know
the destination. When the flag is turned off, unicast traffic
without an FDB will not be forwarded to the specified port.
... and it seems to be the reasonable thing to do by default.
Rename to follow the follow the style of other options.
In general "positive" options are preferred to "negative" ones,
because they are easier to describe and easier for humans to
parse (c.f. the shortening on the man page entry).
- Make sure that the IPv6PrivacyExtensions=yes results in
prefer-temporary, not prefer-public.
- Introduce special enum value "kernel" to leave setting unset, similar
how we have it for the IP forwarding settings.
- Bring the enum values in sync with the the strings we parse for them,
to the level this makes sense (specifically, rename "disabled" to
"no", and "prefer-temporary" to "yes").
- Make sure we really set the value to to "no" by default, the way it is
already documented in the man page.
- Fix whitespace error.
- Make sure link_ipv6_privacy_extensions() actually returns the correct
enum type, rather than implicitly casting it to "bool".
- properly size formatting buffer for ipv6 sysctl value
- Don't complain if /proc/sys isn't writable
- Document that the enum follows the kernel's own values (0 = off, 1 =
prefer-public, 2 = prefer-temporary)
- Drop redundant negating of error code passed to log_syntax()
- Manpage fixes
This fixes a number of issues from PR #417
We refer to the same sysctl-setting twice, which is misleading. Correctly
list all global forwarding options. As we _always_ change the forwarding
setting on links, they will get disabled by default. The global sysctl
defaults thus will not have any effect.
This did not really work out as we had hoped. Trying to do this upstream
introduced several problems that probably makes it better suited as a
downstream patch after all. At any rate, it is not releaseable in the
current state, so we at least need to revert this before the release.
* by adjusting the path to binaries, but not do the same thing to the
search path we end up with inconsistent man-pages. Adjusting the search
path too would be quite messy, and it is not at all obvious that this is
worth the effort, but at any rate it would have to be done before we
could ship this.
* this means that distributed man-pages does not make sense as they depend
on config options, and for better or worse we are still distributing
man pages, so that is something that definitely needs sorting out before
we could ship with this patch.
* we have long held that split-usr is only minimally supported in order
to boot, and something we hope will eventually go away. So before we start
adding even more magic/effort in order to make this work nicely, we should
probably question if it makes sense at all.
In particular, use /lib/systemd instead of /usr/lib/systemd in distributions
like Debian which still have not adopted a /usr merge setup.
Use XML entities from man/custom-entities.ent to replace configured paths while
doing XSLT processing of the original XML files. There was precedent of some
files (such as systemd.generator.xml) which were already using this approach.
This addresses most of the (manual) fixes from this patch:
http://anonscm.debian.org/cgit/pkg-systemd/systemd.git/tree/debian/patches/Fix-paths-in-man-pages.patch?h=experimental-220
The idea of using generic XML entities was presented here:
http://lists.freedesktop.org/archives/systemd-devel/2015-May/032240.html
This patch solves almost all the issues, with the exception of:
- Path to /bin/mount and /bin/umount.
- Generic statements about preference of /lib over /etc.
These will be handled separately by follow up patches.
Tested:
- With default configure settings, ran "make install" to two separate
directories and compared the output to confirm they matched exactly.
- Used a set of configure flags including $CONFFLAGS from Debian:
http://anonscm.debian.org/cgit/pkg-systemd/systemd.git/tree/debian/rules
Installed the tree and confirmed the paths use /lib/systemd instead of
/usr/lib/systemd and that no other unexpected differences exist.
- Confirmed that `make distcheck` still passes.
This reverts commit 43c6d5abac
(and a small part of 4046d8361c)
It turns out we don't actually need to set the global ip_forward setting.
The only relevant setting is the one on each interface.
What the global toggle actually does is switch forwarding on/off for all
currently present interfaces and change the default for new ones.
That means that by setting the global ip_forward we
- Introduce a race condition, because if the interface with IPForward=yes
is brought up after one with IPForward=no, both will have forwarding
enabled, because the global switch turns it on for all interfaces.
If the other interface comes up first networkd correctly sets forward=0
and it doesn't get overridden.
- Change the forwarding setting for interfaces that networkd is not
configured to touch, even if the user disabled forwarding via sysctl,
either globally or per-interface
As forwarding works fine without this, as long as all relevant interfacest
individually set IPForward=yes: just drop it
This means that non-networkd interfaces use the global default while
networkd interfaces default to off if IPForward isn't given.
Lennart Poettering