I wished to report that IP aliasing, or multi-homing does not work properly with redhat 6.0. For instance please see the scenario below. ifconfig eth0 inet 10.5.4.254 netmask 255.255.255.0 broadcast 10.5.4.255 <ret> route add -net 10.5.4.0 netmask 255.255.255.0 eth0 produces an address for a single "user" on my NIC card. However when I attempt to alias this NIC card as such... ifconfig eth0:2 inet 10.10.10.10 netmask 255.255.255.0 broadcast 10.10.10.255 <ret> route add -net 10.10.10.0 netmask 255.255.255.0 eth0:2 I get another logical device that is not annotated eth0:2 when I type netstat -rn. yet the configured interface is eth0:2 when I type ifconfig. All preivious version of Redhat have this capability and it is very important to my work. The same result is produced when I use the config scripts located in /etc/sysconfig/network-scripts. ifconfig from my box: eth5 Link encap:Ethernet HWaddr 00:40:05:41:4B:17 inet addr:10.5.4.254 Bcast:10.5.4.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:100 Interrupt:11 Base address:0xec00 eth5:0 Link encap:Ethernet HWaddr 00:40:05:41:4B:17 inet addr:10.10.10.10 Bcast:10.10.10.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 Interrupt:11 Base address:0xec00 netstat -rn 10.5.0.254 0.0.0.0 255.255.255.255 UH 0 0 0 eth1 10.5.2.254 0.0.0.0 255.255.255.255 UH 0 0 0 eth3 10.5.4.254 0.0.0.0 255.255.255.255 UH 0 0 0 eth5 10.5.1.254 0.0.0.0 255.255.255.255 UH 0 0 0 eth2 10.5.3.254 0.0.0.0 255.255.255.255 UH 0 0 0 eth4 206.71.183.0 0.0.0.0 255.255.255.224 U 0 0 0 eth0 10.5.4.0 0.0.0.0 255.255.255.0 U 0 0 0 eth5 10.5.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth2 10.10.10.0 0.0.0.0 255.255.255.0 U 0 0 0 eth5 10.5.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 10.5.3.0 0.0.0.0 255.255.255.0 U 0 0 0 eth4 10.5.2.0 0.0.0.0 255.255.255.0 U 0 0 0 eth3 127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
Behavior confirmed in test lab. Appears as if netstat is simply truncating the interface designation, as everything functions correctly with the aliased interface.
This is directly caused by a kernel change -- check the contents of /proc/net/routes. It's not something that we can unilaterally change. It's not precisely a bug; it's a change in behaviour. Sorry that it is causing you trouble...