GNOME Bugzilla – Bug 690212
detect and handle network address conflicts
Last modified: 2020-11-12 14:30:41 UTC
* Ferry Huberts 2010-06-25 07:12:17 EDT Description of feature request: NetworkManager should detect network address conflicts upon bringing up interfaces and let the user decide what to do. Last week I connected my HTC Desire Android phone to my Fedora 13 laptop and tethered it to connect to the internet. It didn't work. After a bit of investigation this was caused by an IP address range conflict caused by the phone assigning the same network address range (192.168.100.100/24) as one of my libvirt 'private' bridges. Shutting down the offending bridge made it work (obviously) Since I'm a network expert this was quickly found. A regular user will NOT know how to solve this problem therefore NetworkManager should detect the problem and let the user decide what to do. For example: decide what interface to shut down, bring the new interface up and shut another down or not bring the new interface up at all, etc. This is a usability issue. ... * Pavel Simerda 2012-03-21 04:23:54 EDT “or allow something like a plugin to handle this through some sort of callback/notification.” It could be, and it could be even configurable. I suggest moving this request in the Gnome bugzilla. As you can see, it's here since 2010. But it may happen there too, as NM needs work in many areas. See https://bugzilla.redhat.com/show_bug.cgi?id=607989
Thanks for moving.
We recently concluded that NetworkManager should separate device route addition from address addition (kernel would be told not to handle the route addition). Then one address can be safely assigned to multiple interfaces with the default route setting saying which one would be used. Route conflicts could then be handled by assigning a priority order to the running connections and either propagating the order into the kernel metric, or avoiding addition of conflicting routes, keeping only the best one. For source routing (bug 709478) and similar use cases, the metric way seems to be preferable.
bugzilla.gnome.org is being shut down in favor of a GitLab instance. We are closing all old bug reports and feature requests in GNOME Bugzilla which have not seen updates for a long time. If you still use NetworkManager and if you still see this bug / want this feature in a recent and supported version of NetworkManager, then please feel free to report it at https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/issues/ Thank you for creating this report and we are sorry it could not be implemented (workforce and time is unfortunately limited).