Keepalived LoadBalacing

LVS Config

## Pool ID
virtual_server <WAN "frontend" IP> 80 {
        delay_loop 6
        lb_algo sh     # source hash
        lb_kind NAT
        protocol TCP

        real_server <LAN "backend" IP Server 1> 80 {
                weight 1
                TCP_CHECK {
                        connect_timeout 3
                }
        }
        real_server <LAN "backend" IP Server 2> 80 {
                weight 1
                TCP_CHECK {
                        connect_timeout 3
                }
        }
}

virtual_server <WAN "frontend" IP> 443 {
        delay_loop 6
        lb_algo sh     # source hash
        lb_kind NAT
        protocol TCP

        real_server <LAN "backend" IP Server 1> 443 {
                weight 1
                TCP_CHECK {
                        connect_timeout 3
                }
        }
        real_server <LAN "backend" IP Server 2> 443 {
                weight 1
                TCP_CHECK {
                        connect_timeout 3
                }
        }
}

VRRP

vrrp_instance VI_LOCAL {
        state MASTER
        interface eth1
        virtual_router_id 51
        priority 101
        virtual_ipaddress {
                10.X.X.X
        }

        track_interface {
                eth0
                eth1
        }

}

vrrp_instance VI_PUB {
        state MASTER
        interface eth0
        virtual_router_id 52
        priority 101
        virtual_ipaddress {
                X.X.X.X
        }
        track_interface {
                eth0
                eth1
        }
}

vrrp_instance VI_PUB2 {
        state MASTER
        interface eth0
        virtual_router_id 53
        priority 101
        virtual_ipaddress {
                X.X.X.X
        }

        track_interface {
                eth0
                eth1
	}
}

sysctl

# Use ip that are not configured locally (HAProxy + KeepAlived requirements)
net.ipv4.ip_nonlocal_bind = 1

# Enable packet forwarding
net.ipv4.ip_forward=1

# Disables IP source routing
net.ipv4.conf.all.accept_source_route = 0

# Enable IP spoofing protection, turn on source route verification
net.ipv4.conf.all.rp_filter = 1

# Disable ICMP Redirect Acceptance
net.ipv4.conf.all.accept_redirects = 0

# Decrease the time default value for tcp_fin_timeout connection
net.ipv4.tcp_fin_timeout = 15

# Decrease the time default value for tcp_keepalive_time connection
net.ipv4.tcp_keepalive_time = 1800

# Enable TCP SYN Cookie Protection
net.ipv4.tcp_syncookies = 1

# Enable ignoring broadcasts request
net.ipv4.icmp_echo_ignore_broadcasts = 1

# Enable bad error message Protection
net.ipv4.icmp_ignore_bogus_error_responses = 1

# Log Spoofed Packets, Source Routed Packets, Redirect Packets
net.ipv4.conf.all.log_martians = 1

# Increases the size of the socket queue
net.ipv4.tcp_max_syn_backlog = 1024

# Increase the tcp-time-wait buckets pool size
net.ipv4.tcp_max_tw_buckets = 1440000

# Arp
net.ipv4.conf.lo.rp_filter = 0
net.ipv4.conf.all.arp_announce = 2
net.ipv4.conf.all.arp_ignore = 1

DR

vim /etc/modules

iptable_mangle
xt_multiport
xt_MARK
ip_vs
ip_vs_rr
ip_vs_nq
ip_vs_wlc

${IPTABLES} -t mangle -A PREROUTING -p tcp -d <VIP-WAN>/32 -j MARK --set-mark 0x1

Keepalived

virtual_server fwmark 1 {
        delay_loop 10
        lb_algo lc 
        lb_kind DR
        protocol TCP
	persistence_timeout 28800

        real_server <WAN-WEB1> 0 {
                weight 1
                TCP_CHECK {
			connect_port 443 
                        connect_timeout 3
                }
        }
        real_server <WAN-WEB2> 0 {
                weight 2
                TCP_CHECK {
			connect_port 443
                        connect_timeout 3
                }
        }
}