On Sun, 18 Aug 2002, Matthew G. Marsh grunted something like:
> > ifconfig eth0 10.5.5.8 broadcast 10.5.5.255 netmask 255.255.255.0
> > ip -f inet addr add 10.5.5.1 dev eth0 scope link
> > ip -f inet addr add 10.5.5.2 dev eth0 scope link
>
> Why do you use the 'scope link' statements?
Why do I use the 'scope link' argument, or the statement as a whole?
Those two statements give the same effect as aliases (more or less)
without having to ifconfig eth0:X for each X. My understanding was the
'scope link' part was useful in keeping the effects of the command local
to the device. However, I also did not generate these commands on my own:
fwbuilder is doing that. We're trying to get a setup that can be easily
managed by other people who may not have the same experience with
command-line tools and such.
> And as far as your original question try the following:
>
> ip -f inet addr add 10.5.5.8/24 dev eth0 brd +
> ip -f inet addr add 10.5.5.1 dev eth0 scope link brd 10.5.5.255
> ip -f inet addr add 10.5.5.2 dev eth0 scope link brd 10.5.5.255
Aha! At the suggestion of the iproute2 documentation, and another person
on the linux-ha list, I tried using 'brd +' on the aliased IPs, but
apparently we were reading the docs wrong. Setting it explicitly works!
> And also you will then have 'ifconfig eth0':
>
> eth0 Link encap:Ethernet HWaddr 00:C0:9F:0C:5F:DB
> inet addr:10.5.5.2 Bcast:10.5.5.255 Mask:255.255.255.255
> UP BROADCAST MULTICAST MTU:1500 Metric:1
>
> Work for you?
Exactly what we need. Now the ioctl can pull the broadcast address.
> And if I am way off base here due to jumping in just ignore me.
Not at all, thanks for the suggestion. It seems now that I need to try to
encourage the fwbuilder folks to specify the broadcast address on each
alias. At the very least, I should be able to whip out a patch to do
it, and hopefully they'll accept it.
/* kevin@xxxxxxxxxxx http://devel.pheared.net/ */
/* Network Security Engineer http://pheared.net/~kevin */
/* Sabotage will set us free. Throw a rock in the machine. */
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