Load Balancer And CPanel

I'm using Virtuozzo on two server.

1) Can I do this with only ONE Load Balancer?

I wish I could have many "LB", like one for the WWW serveur, an other one for the DB serveur, my "personnal" VPS without LB...

i.e. :
WWW -> SRV1 SRV2
DB1 -> DB1 DB2
EXCESSNET -> EXCESSNET1

Do I need 3 LB to do this or I can do it with only one? The screenshot of Barracuda LB seem to show many "virtual LB", so I guest it's a yes?

2) So... it's service only?

On the Barracuda and some page, they are talking about "service" and not "server" LB. Can I LB a whole serveur ? Like all service from an IP xxx.xxx.xxx.234 to a server ? Or I can only do "HTTP -> SRV1" "DNS -> SRV1"? If no, what happen to service that the LB didn't know (like cPanel)?

3) An Internal Network? what About cPanel?

According to my search, LB are working like this:

EXTERNAL IP of SERVICE (xxx.xxx.xxx.200) -> INTERNAL IP SERVER 1(10.0.0.25), INTERNAL IP SERVER 2 (10.0.0.26)

So, I need to configure the server with an Internal IP cause else, it will conflit on the "local network". The probleme is, cPanel will be using the "Internal IP" to make all of his configuration... so if a user add a new website, he will configure it with 10.0.0.25, this won't since the external IP will be xxx.xxx.xxx.200 and Apache won't anwser to this virtual host. What can I do?

Can I do this ? (same internal IP as the external?)
EXTERNAL IP (70.234.125.123) -> SERVER 1 INTERNAL IP (70.234.125.123), SERVER 2 INTERNAL IP (10.0.0.26)

If yes, I will configure the second serveur without cPanel and only sync the configuration and files. So in case of "crash" of the server 1, cPanel won't be working, but website won't be down...