linux 服务器禁ping : echo 1 >  /proc/sys/net/ipv4/icmp_echo_ignore_all

source  /proc/sys/net/ipv4/icmp_echo_ignore_all


恢复ping :echo 0 >  /proc/sys/net/ipv4/icmp_echo_ignore_all

soucre  /proc/sys/net/ipv4/icmp_echo_ignore_all