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read-only mirror of https://gitlab.freedesktop.org/NetworkManager/NetworkManager
f0de7d347f
Previously, we would add exclusive routes via netlink message flags NLM_F_CREATE | NLM_F_REPLACE for RTM_NEWROUTE. Similar to `ip route replace`. Using that form of RTM_NEWROUTE message, we could only add a certain route with a certain network/plen,metric triple once. That was already hugely inconvenient, because - when configuring routes, multiple (managed) interfaces may get conflicting routes (multihoming). Only one of the routes can be actually configured using `ip route replace`, so we need to track routes that are currently shadowed. - when configuring routes, we might replace externally configured routes on unmanaged interfaces. We should not interfere with such routes. That was worked around by having NMRouteManager (and NMDefaultRouteManager). NMRouteManager would keep a list of the routes which NetworkManager would like to configure, even if momentarily being unable to do so due to conflicting routes. This worked mostly well but was complicated. It involved bumping metrics to avoid conflicts for device routes, as we might require them for gateway routes. Drop that now. Instead, use the corresponding of `ip route append` to configure routes. This allows NetworkManager to confiure (almost) all routes that we care. Especially, it can configure all routes on a managed interface, without replacing/interfering with routes on other interfaces. Hence, NMRouteManager becomes obsolete. It practice it is a bit more complicated because: - when adding an IPv4 address, kernel will automatically create a device route for the subnet. We should avoid that by using the IFA_F_NOPREFIXROUTE flag for IPv4 addresses (still to-do). But as kernel may not support that flag for IPv4 addresses yet (and we don't require such a kernel yet), we still need functionality similar to nm_route_manager_ip4_route_register_device_route_purge_list(). This functionality is now handled via nm_platform_ip4_dev_route_blacklist_set(). - trying to configure an IPv6 route with a source address will be rejected by kernel as long as the address is tentative (see related bug rh#1457196). Preferably, NMDevice would keep the list of routes which should be configured, while kernel would have the list of what actually is configured. There is a feed-back loop where both affect each other (for example, when externally deleting a route, NMDevice must forget about it too). Previously, NMRouteManager would have the task of remembering all routes which we currently want to configure, but cannot due to conflicting routes. We get rid of that, because now we configure non-exclusive routes. We however still will need to remember IPv6 routes with a source address, that currently cannot be configured yet. Hence, we will need to keep track of routes that currently cannot be configured, but later may be. That is still not done yet, as NMRouteManager didn't handle this correctly either. |
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| data | ||
| dispatcher | ||
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| examples | ||
| introspection | ||
| libnm | ||
| libnm-core | ||
| libnm-glib | ||
| libnm-util | ||
| m4 | ||
| man | ||
| po | ||
| shared | ||
| src | ||
| tools | ||
| vapi | ||
| .dir-locals.el | ||
| .gitignore | ||
| .travis.yml | ||
| AUTHORS | ||
| autogen.sh | ||
| ChangeLog | ||
| configure.ac | ||
| CONTRIBUTING | ||
| COPYING | ||
| linker-script-binary.ver | ||
| linker-script-devices.ver | ||
| linker-script-settings.ver | ||
| MAINTAINERS | ||
| Makefile.am | ||
| Makefile.examples | ||
| Makefile.glib | ||
| Makefile.vapigen | ||
| NetworkManager.pc.in | ||
| NEWS | ||
| README | ||
| TODO | ||
| valgrind.suppressions | ||
| zanata.xml | ||
****************** 2008-12-11: NetworkManager core daemon has moved to git.freedesktop.org! git clone git://git.freedesktop.org/git/NetworkManager/NetworkManager.git ****************** Networking that Just Works -------------------------- NetworkManager attempts to keep an active network connection available at all times. The point of NetworkManager is to make networking configuration and setup as painless and automatic as possible. NetworkManager is intended to replace default route, replace other routes, set IP addresses, and in general configure networking as NM sees fit (with the possibility of manual override as necessary). In effect, the goal of NetworkManager is to make networking Just Work with a minimum of user hassle, but still allow customization and a high level of manual network control. If you have special needs, we'd like to hear about them, but understand that NetworkManager is not intended for every use-case. NetworkManager will attempt to keep every network device in the system up and active, as long as the device is available for use (has a cable plugged in, the killswitch isn't turned on, etc). Network connections can be set to 'autoconnect', meaning that NetworkManager will make that connection active whenever it and the hardware is available. "Settings services" store lists of user- or administrator-defined "connections", which contain all the settings and parameters required to connect to a specific network. NetworkManager will _never_ activate a connection that is not in this list, or that the user has not directed NetworkManager to connect to. How it works: The NetworkManager daemon runs as a privileged service (since it must access and control hardware), but provides a D-Bus interface on the system bus to allow for fine-grained control of networking. NetworkManager does not store connections or settings, it is only the mechanism by which those connections are selected and activated. To store pre-defined network connections, two separate services, the "system settings service" and the "user settings service" store connection information and provide these to NetworkManager, also via D-Bus. Each settings service can determine how and where it persistently stores the connection information; for example, the GNOME applet stores its configuration in GConf, and the system settings service stores it's config in distro-specific formats, or in a distro- agnostic format, depending on user/administrator preference. A variety of other system services are used by NetworkManager to provide network functionality: wpa_supplicant for wireless connections and 802.1x wired connections, pppd for PPP and mobile broadband connections, DHCP clients for dynamic IP addressing, dnsmasq for proxy nameserver and DHCP server functionality for internet connection sharing, and avahi-autoipd for IPv4 link-local addresses. Most communication with these daemons occurs, again, via D-Bus. Why doesn't my network Just Work? Driver problems are the #1 cause of why NetworkManager sometimes fails to connect to wireless networks. Often, the driver simply doesn't behave in a consistent manner, or is just plain buggy. NetworkManager supports _only_ those drivers that are shipped with the upstream Linux kernel, because only those drivers can be easily fixed and debugged. ndiswrapper, vendor binary drivers, or other out-of-tree drivers may or may not work well with NetworkManager, precisely because they have not been vetted and improved by the open-source community, and because problems in these drivers usually cannot be fixed. Sometimes, command-line tools like 'iwconfig' will work, but NetworkManager will fail. This is again often due to buggy drivers, because these drivers simply aren't expecting the dynamic requests that NetworkManager and wpa_supplicant make. Driver bugs should be filed in the bug tracker of the distribution being run, since often distributions customize their kernel and drivers. Sometimes, it really is NetworkManager's fault. If you think that's the case, please file a bug at http://bugzilla.gnome.org and choose the NetworkManager component. Attaching the output of /var/log/messages or /var/log/daemon.log (wherever your distribution directs syslog's 'daemon' facility output) is often very helpful, and (if you can get) a working wpa_supplicant config file helps enormously.