IP Spoofing and Load balancing

Hi,

I need some help to determine if I need IP spoofing or not.

I have 4 load generators, load balancer and five web servers behind.

If load balancer algorithm makes determination based on client IP then 4 load generators is enough to spread load of few hundred users equally or I still need IP spoofing.

Persistence is maintained by session cookies and the question is do I need to use web_cleanup_cookies function before the script goes to the next iteration?

Your help is appreciated.

Thanks,

Garry