linux-屏蔽ping回显-131

 开启本机的屏蔽ping的回显

# echo 'net.ipv4.icmp_echo_ignore_all=1'>> /etc/sysctl.conf     ----添加忽略

# sysctl -p ----立即执行

net.ipv4.ip_forward = 0

net.ipv4.conf.default.rp_filter = 1

net.ipv4.conf.default.accept_source_route = 0

kernel.sysrq = 0

kernel.core_uses_pid = 1

net.ipv4.tcp_syncookies = 1

kernel.msgmnb = 65536

kernel.msgmax = 65536

kernel.shmmax = 68719476736

kernel.shmall = 4294967296

net.ipv4.icmp_echo_ignore_all = 1

 

从其他物理主机ping本机

C:\Documents and Settings\liweiyan>ping 192.168.222.222

 

Pinging 192.168.222.222 with 32 bytes of data:

 

Reply from 192.168.222.222: bytes=32 time<1ms TTL=63

Reply from 192.168.222.222: bytes=32 time<1ms TTL=63

Reply from 192.168.222.222: bytes=32 time<1ms TTL=63

Reply from 192.168.222.222: bytes=32 time<1ms TTL=63

 

Ping statistics for 192.168.222.222:

    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),

Approximate round trip times in milli-seconds:

    Minimum = 0ms, Maximum = 0ms, Average = 0ms

-----------开启本机的屏蔽ping的回显之后，

C:\Documents and Settings\liweiyan>ping 192.168.222.222

 

Pinging 192.168.222.222 with 32 bytes of data:

 

Request timed out.

所以ping不是唯一的一个测试物理主机是否连通的方式，如果目标主机屏蔽了ping有可能可以和目标主机通信，只是ping不通而已。