[CentOS] C5: correct place for routing scripts?

Hello

I have several Centos 4 and Centos 5 servers. Because of the nature of
the environment, there are some static arp entries made with arp
command and then source routing made with "ip rule/ip route"
-commands.

Those commands are now placed at /etc/rc.d/rc.local which is bad: if
server is rebooted, those commands will be done correctly but if
administrator restarts network with "/etc/init.d/network restart",
source routes will disappear.

RedHat/Centos qualified admin knows only about network restart init
script, so I try to avoid doing any hacks.
I could edit the init script (/etc/init.d/network) but changes could
disappear with updates.


So, what is the correct place for different commands (arp, ip,
whatever) that is executed
(a) once when network started
(b) once when network stopped (I don't need but nice to know)
(c) once per every interface (I don't need but nice to know)


Best Regards,
Kimmo