keepalived provides a strong and robust health checking for LVS clusters. It nginx implements a framework of health checking on multiple layers for server failover, and VRRPv2 stack to handle director failover. How do I install and configure Keepalived for reverse proxy server such as nginx or lighttpd?
How do I restrict the number of connections used by a single IP address to my server for port 80 and 25 using iptables?
You need to use the connection limit modules which allows you to restrict the number of parallel TCP connections to a server per client IP address (or address block). This is useful to protect your server or vps box against flooding, spamming or content scraping.
1. Setup More than one IP address for one network interface:
The file which contains descriptions of the network interfaces on Ubuntu or debian is /etc/nework/interfaces
A network interface (material) by default is referenced by eth0 so if you have more than one it would be eth1 eth2,