vim /etc/sysctl.conf net.ipv4.ip_forward = 1 net.ipv4.conf.default.rp_filter = 0 echo "0">/proc/sys/net/ipv4/conf/lo/rp_filter sysctl -a | egrep "ipv4.*(accept|send)_redirects" | awk -F "=" '{print$1"= 0"}' >> /etc/sysctl.conf sysctl -p sudo yum -y install openswan ipsec --version Linux Libreswan 3.15 (netkey) on 2.6.32-696.1.1.el6.x86_64