Add an IP alias to ethernet interface

Dan Nicholson dbn.lists at gmail.com
Fri Jun 8 06:59:50 PDT 2007


On 6/8/07, Andrew Beverley <andy at andybev.com> wrote:
> On Thu, 2007-06-07 at 15:00 -0500, Zachary Kotlarek wrote:
> > On Jun 6, 2007, at 6:34 PM, Bryan Kadzban wrote:
> >
> > > I suspect the alias option exists in ip for compatibility with
> > > ifconfig,
> > > and no other reason.  But I don't know that for sure.
> >
> > I believe that's correct. In the past the kernel supported aliases
> > with independent statistics and the like, but that hasn't been true
> > for years. Modern kernels don't treat aliases interfaces any
> > different than secondary addresses on the main interface -- both
> > interface statistics and iptables traversal treat all aliases just
> > like the main interface, and the alternate label is only maintained
> > to support legacy configurations and tools.
>
> Okay, I see. Nonetheless would it be possible to still either get the
> script altered anyway, or to add a note to the networking page of the
> book stating that it is just a matter of adding a second config file in
> the interface directory for a second address.

I agree with Andy here. Regardless of the reason for alias/label, if
it's used in iproute2, we should expose the functionality. This page I
found on linux-ip.net seems to promote using labels when there are
multiple addresses assigned to an interface.

http://linux-ip.net/html/tools-ip-address.html

Unless someone knows problems that will be introduced, I'm gonna go
ahead and try to get Andy's patch adapted to ipv4-static and get a
blurb on ALIAS in the book.

--
Dan



More information about the lfs-dev mailing list