當我嘗試ping我局域網上的廣播地址時,即使有很多主機連接到局域網,它每次只顯示3臺主機的ICMP應答。Pinging廣播地址的問題
對於廣播地址,我也
$ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:1b:38:09:0b:26
inet addr:172.30.120.152 Bcast:172.30.127.255 Mask:255.255.248.0
inet6 addr: fe80::21b:38ff:fe09:b26/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:831096 errors:0 dropped:0 overruns:0 frame:0
TX packets:13022 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:66620362 (66.6 MB) TX bytes:3099025 (3.0 MB)
Interrupt:21 Base address:0x2000
我用BCAST地址172.30.127.255來ping大家...
$ping -b 172.30.127.255
WARNING: pinging broadcast address
PING 172.30.127.255 (172.30.127.255) 56(84) bytes of data.
64 bytes from 172.30.120.1: icmp_seq=1 ttl=255 time=0.809 ms
64 bytes from 172.30.120.62: icmp_seq=1 ttl=64 time=1.06 ms (DUP!)
64 bytes from 172.30.120.50: icmp_seq=1 ttl=255 time=3.97 ms (DUP!)
64 bytes from 172.30.120.1: icmp_seq=2 ttl=255 time=0.364 ms
64 bytes from 172.30.120.62: icmp_seq=2 ttl=64 time=0.412 ms (DUP!)
64 bytes from 172.30.120.50: icmp_seq=2 ttl=255 time=1.48 ms (DUP!)
64 bytes from 172.30.120.1: icmp_seq=3 ttl=255 time=0.452 ms
64 bytes from 172.30.120.62: icmp_seq=3 ttl=64 time=0.506 ms (DUP!)
64 bytes from 172.30.120.50: icmp_seq=3 ttl=255 time=1.64 ms (DUP!)
爲什麼只有3臺主機到我的響應ping。這是由ifconfig給出的bcast地址而不是要使用的地址嗎? 我認爲這可能是我無法對局域網上的系統執行放大攻擊的原因。我注射了我的朋友的主機 的僞造源地址的ICMP回聲報文,發送到這個廣播地址,並失望地看到,他的帶寬並沒有受到影響......
請解釋...