主要记录一下命令

设置TCP最大报文长度，一般情况下自己可以算出来。

但是很多情况下并不一定，还是需要自己测试。

LINUX
 

当包是1472字节并且不拆包，能够传送正确；
[root@sxx1314 ~]# ping -c 3 -s 1472 -M do www.baidu.com
PING www.a.shifen.com (10.10.0.230) 1472(1500) bytes of data.
1480 bytes from 10.10.0.230: icmp_seq=1 ttl=64 time=0.345 ms
1480 bytes from 10.10.0.230: icmp_seq=2 ttl=64 time=0.303 ms
1480 bytes from 10.10.0.230: icmp_seq=3 ttl=64 time=0.314 ms
--- 10.1.0.230 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2000ms
rtt min/avg/max/mdev = 0.303/0.320/0.345/0.027 ms
当包是1473字节并且不拆包，加上28字节的包头，大于设定值1500，发生错误。
[root@sxx1314 ~]# ping -c 3 -s 1473 -M www.baidu.com
PING www.a.shifen.com (10.10.0.230) 1473(1501) bytes of data.
From 10.10.34.1 icmp_seq=1 Frag needed and DF set (mtu = 1500)
From 10.10.34.1 icmp_seq=1 Frag needed and DF set (mtu = 1500)
From 10.10.34.1 icmp_seq=1 Frag needed and DF set (mtu = 1500)
--- 10.1.0.230 ping statistics ---
0 packets transmitted, 0 received, +3 errors

WIN

测试方法

ping –l 1472 –f  www.baidu.com