/etc/rc.d/rc.local 파일에 아래의 설정값들을 입력하다. sysctl -w net.ipv4.ip_default_ttl=64 sysctl -w net.ipv4.ip_forward=0 sysctl -w net.ipv4.ipfrag_time=15 sysctl -w net.ipv4.tcp_syn_retries=3 sysctl -w net.ipv4.tcp_retries1=3 sysctl -w net.ipv4.tpc_retries2=7 sysctl -w net.ipv4.conf.eth0.rp_filter=2 sysctl -w net.ipv4.conf.lo.rp_filter=2 sysctl -w net.ipv4.conf.default.rp_filter=2 sysctl -w net.ipv4.conf.all..