I have looked for this in very many forums but I didn't find something.

I have a problem to add virtual interface on fedora 8.
I've done installation of fedora 8 as server.
I have ip from dhcp server and after NAT.
So my ip address is
Subnet mask and default gateway is
I need to create two virtual interfaces eth0:1 and eth0:2.
I have done the following things:

ifconfig eth0:1 netmask up
ifconfig eth0:2 netmask up

After " ifconfig -a "

I saw that I have new interfaces but when I'll try to add them to the kernel IP routing table I have some strange problem.

route add -net netmask

Error : SIOCADDRT invalid argument

So I'd like to see after "route"
that I have in column Iface eth0:1 and etho:2
now I see only eth0.

Thank you very much for help.