Desired behaviour of "ifconfig -alias"

Patrick M. Hausen hausen at
Tue Feb 13 19:10:22 UTC 2007


On Tue, Feb 13, 2007 at 07:37:17PM +0100, Oliver Fromme wrote:
> Freddie Cash wrote:
>  > For a set of IPs in the same subnet on the same interface, wouldn't the 
>  > primary IP be the one with the proper netmask, and all IPs with netmasks 
>  > of /32 be secondary?
> That's historic.  :-)   Old versions of FreeBSD indeed
> required the netmask of the "aliases" to be /32 in that
> case.  But it's no longer the case.

WTF? Er, sorry, what did I miss? This is complete news to me
and I'm really surprised. I had that same thought as Freddie had
when I read this thread, but did not find the time to answer until

Was there a HEADS UP or something?

>  > In that situation, wouldn't deleting the primary IP 
>  > cause connection issues for the rest of the IPs?
> No.  I can delete _any_ of the above IP addresses, and the
> others would still work perfectly fine.  I already did
> things like that (on a different machine).

_If_ they all share the same netmask when they are part
of the same prefix.

As much as I appreciate the change, this is a big POLA violation.
I considered the "netmask 0xffffffff" cast in concrete until now.

Thanks for clarifying.
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