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User-Agent: Mozilla/4.0 (compatible; MSIE 5.01; Windows NT 5.0)

Description of problem:
ifup allways add a route for a non-aliases interface, even when the interface 
doesn't connect to a "proper" segment. Example: eth2 connect to a DMZ segment 
with machines having IP addresses taken from the segment connected to eth1 
interface (and you use proxy-arp to let machines from eth1 and eth2 segments 
think they are on the same wire).

Version-Release number of selected component (if applicable):


How reproducible:
Always

Steps to Reproduce:
1. Define eth1 with ip 10.1.1.1, netmask 255.255.255.0
2. Define eth2 with ip 10.1.1.2, netmask 255.255.255.255 (yes, because we 
really don't have a segment here)
3. service network restart
	

Actual Results:  Route to 0.0.0.0/0 is thru eth2 now.
Whoo!!! we just changed the default route.

Expected Results:  No route added at all.
We except that a netmask of 255.255.255.255 in ifcfg-ethN means "no network 
here".
We solved it changing line 236 in ifup script from:
   if [ "${ISALIAS}" = no ] ; then
to
   if [ "${ISALIAS}" = no -a "${PREFIX}" != "32"] ; then
because, after all, there is no point in adding/replacing a route when the 
netmask is 255.255.255.255.

Additional info:

While our net design may be a little non-ortodox, that scheme work in RedHat 
7.1 and earlier.