Subject: Re: alias addresses vs routing
To: None <tech-net@netbsd.org>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
List: tech-net
Date: 02/21/2006 18:33:42
>> # ifconfig ex0 10.100.0.1/30
>> # ifconfig ex0 10.100.0.100/24 alias
>> Note in particular the lack of a route to 10.100/24 corresponding to
>> the "alias" address.
> if you delete the first address (the /30), the route for /24
> "reappears". may be a bug in netstat?
That actually makes sense.
I just tried some experiments with all the addresses being aliases, to
avoid issues with the way an alias gets promoted to primary if the
primary address is deleted:
# ifconfig ne2 10.100.1.1/24
That address remained primary throughout the experiments.
If I add 10.100.0.1/30 and then 10.100.0.100/24, netstat shows me a
route to the /30. But if I add them in the other order, it shows me
the route to the /24 and fails to show the route to the /30.
I now suspect both routes are actually present, and the problem is some
kind of confusion in netstat over two routes with "the same
destination" (10.100.0.0). Someday if I get the leisure I may dig into
the code and see if I can figure out what's up.
/~\ The ASCII der Mouse
\ / Ribbon Campaign
X Against HTML mouse@rodents.montreal.qc.ca
/ \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B