首先安装openswan
yum install openswan
修改内核参数启用转发和禁止重定向
修改sysctl.conf文件
vi /etc/sysctl.conf
添加以下内容
net.ipv4.conf.default.send_redirects=0
net.ipv4.icmp_ignore_bogus_error_responses=1
net.ipv4.conf.default.log_martians=0
net.ipv4.conf.all.log_martians=0
net.ipv4.conf.default.accept_source_route=0
net.ipv4.conf.all.accept_redirects=0
net.ipv4.conf.default.accept_redirects=0
net.core.xfrm_larval_drop=1
net.ipv4.ip_forward = 1
net.ipv4.conf.all.accept_redirects = 0
net.ipv4.conf.all.send_redirects = 0