On Fri, 2012-08-31 at 09:56 +0200, Josselin Mouette wrote:
> Le jeudi 30 août 2012 à 22:19 +0200, Wouter Verhelst a écrit :
> > On Fri, Aug 24, 2012 at 10:44:11AM +0200, Andrew Shadura wrote:
> > > How do you suppose it's possible to undo arbitrary network
> > > configuration done by arbitrary set of tools when there's no central
> > > place to hold such information (and can't possibly be)?
> >
> > Actually, the kernel holds that information. Any tool can just query the
> > kernel for information, and decide what to do with what's returned.
>
> Yes it does, but does it hold it in a meaningful, structured way? In
> complex setups, for example, there might be no certain way to say which
> interface is related to which route.
I wish you would give an example.
> Or to tell which low-level
> interface another interface depends on (think tunnels managed by
> userland tools).
You're thinking about packet forwarding in userland?
> Actually if there was at least a *standard*, low-level (or in-kernel)
> tool to return structured information about the current network
> configuration, maybe high-level network tools (such as ifupdown and NM)
> could be redesigned in a completely different, much more compatible,
> way.
The kernel API is called rtnetlink (or NETLINK_ROUTE) and NM already
uses it. Not all device relationships are properly represented through
it yet, but people are working on it.
Ben.
--
Ben Hutchings
Theory and practice are closer in theory than in practice.
- John Levine, moderator of comp.compilers
Attachment:
signature.asc
Description: This is a digitally signed message part