Linux系統(tǒng)的ping命令是常用的網(wǎng)絡(luò)命令,它通常用來測試與目標主機的連通性,我們經(jīng)常會說“ping一下某機器,看是不是開著”、不能打開網(wǎng)頁時會說“先ping網(wǎng)關(guān)地址192.168.1.1試試”。它通過發(fā)送ICMP ECHO_REQUEST數(shù)據(jù)包到網(wǎng)絡(luò)主機(send ICMP ECHO_REQUEST to network hosts),并顯示響應(yīng)情況,這樣就可以根據(jù)它輸出的信息來確定目標主機是否可訪問(但這不是絕對的)。有些服務(wù)器為了防止通過ping探測到,通過防火墻設(shè)置了禁止ping或者在內(nèi)核參數(shù)中禁止ping,這樣就不能通過ping確定該主機是否還處于開啟狀態(tài)。
linux下的ping命令和windows下的ping執(zhí)行稍有區(qū)別,linux下ping不會自動終止,需要按ctrl+c終止或者用參數(shù)-c指定要求完成的回應(yīng)次數(shù)。
ping [參數(shù)] [主機名或IP地址]
ping命令用于:確定網(wǎng)絡(luò)和各外部主機的狀態(tài);跟蹤和隔離硬件和軟件問題;測試、評估和管理網(wǎng)絡(luò)。如果主機正在運行并連在網(wǎng)上,它就對回送信號進行響應(yīng)。每個回送信號請求包含一個網(wǎng)際協(xié)議(IP)和 ICMP 頭,后面緊跟一個 tim 結(jié)構(gòu),以及來填寫這個信息包的足夠的字節(jié)。缺省情況是連續(xù)發(fā)送回送信號請求直到接收到中斷信號(Ctrl-C)。ping 命令每秒發(fā)送一個數(shù)據(jù)報并且為每個接收到的響應(yīng)打印一行輸出。ping 命令計算信號往返時間和(信息)包丟失情況的統(tǒng)計信息,并且在完成之后顯示一個簡要總結(jié)。ping 命令在程序超時或當接收到 SIGINT 信號時結(jié)束。Host 參數(shù)或者是一個有效的主機名或者是因特網(wǎng)地址。
-d 使用Socket的SO_DEBUG功能。-f 極限檢測。大量且快速地送網(wǎng)絡(luò)封包給一臺機器,看它的回應(yīng)。-n 只輸出數(shù)值。-q 不顯示任何傳送封包的信息,只顯示最后的結(jié)果。-r 忽略普通的Routing Table,直接將數(shù)據(jù)包送到遠端主機上。通常是查看本機的網(wǎng)絡(luò)接口是否有問題。-R 記錄路由過程。-v 詳細顯示指令的執(zhí)行過程。-c 數(shù)目:在發(fā)送指定數(shù)目的包后停止。-i 秒數(shù):設(shè)定間隔幾秒送一個網(wǎng)絡(luò)封包給一臺機器,預(yù)設(shè)值是一秒送一次。-I 網(wǎng)絡(luò)界面:使用指定的網(wǎng)絡(luò)界面送出數(shù)據(jù)包。-l 前置載入:設(shè)置在送出要求信息之前,先行發(fā)出的數(shù)據(jù)包。-p 范本樣式:設(shè)置填滿數(shù)據(jù)包的范本樣式。-s 字節(jié)數(shù):指定發(fā)送的數(shù)據(jù)字節(jié)數(shù),預(yù)設(shè)值是56,加上8字節(jié)的ICMP頭,一共是64ICMP數(shù)據(jù)字節(jié)。-t 存活數(shù)值:設(shè)置存活數(shù)值TTL的大小。命令:
ping 192.168.0.5
輸出:
[yiibai@localhost ~]$ ping 192.168.0.5
PING 192.168.0.5 (192.168.0.5) 56(84) bytes of data.
64 bytes from 192.168.0.5: icmp_seq=1 ttl=64 time=0.498 ms
64 bytes from 192.168.0.5: icmp_seq=2 ttl=64 time=0.384 ms
64 bytes from 192.168.0.5: icmp_seq=3 ttl=64 time=0.486 ms
64 bytes from 192.168.0.5: icmp_seq=4 ttl=64 time=0.482 ms
^C
--- 192.168.0.5 ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 3006ms
rtt min/avg/max/mdev = 0.384/0.462/0.498/0.050 ms
[yiibai@localhost ~]$
命令:
ping 192.168.0.202
輸出:
[yiibai@localhost ~]$ ping 192.168.0.202
PING 192.168.0.202 (192.168.0.202) 56(84) bytes of data.
From 192.168.0.197 icmp_seq=1 Destination Host Unreachable
From 192.168.0.197 icmp_seq=2 Destination Host Unreachable
From 192.168.0.197 icmp_seq=3 Destination Host Unreachable
From 192.168.0.197 icmp_seq=4 Destination Host Unreachable
From 192.168.0.197 icmp_seq=5 Destination Host Unreachable
From 192.168.0.197 icmp_seq=6 Destination Host Unreachable
^C
--- 192.168.0.202 ping statistics ---
7 packets transmitted, 0 received, +6 errors, 100% packet loss, time 6023ms
pipe 4
[yiibai@localhost ~]$
命令:
ping -b 192.168.0.0
輸出:
[yiibai@localhost ~]$ route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
default gateway 0.0.0.0 UG 100 0 0 ens33
192.168.0.0 0.0.0.0 255.255.255.0 U 100 0 0 ens33
[yiibai@localhost ~]$ ping -b 192.168.0.0
WARNING: pinging broadcast address
PING 192.168.0.0 (192.168.0.0) 56(84) bytes of data.
命令:
ping -c 10 www.baidu.com
輸出:
[yiibai@localhost ~]$ ping -c 10 www.baidu.com
PING www.baidu.com (14.215.177.38) 56(84) bytes of data.
64 bytes from 14.215.177.38 (14.215.177.38): icmp_seq=1 ttl=56 time=11.8 ms
64 bytes from 14.215.177.38 (14.215.177.38): icmp_seq=2 ttl=56 time=12.4 ms
64 bytes from 14.215.177.38 (14.215.177.38): icmp_seq=3 ttl=56 time=13.3 ms
64 bytes from 14.215.177.38 (14.215.177.38): icmp_seq=4 ttl=56 time=12.2 ms
64 bytes from 14.215.177.38 (14.215.177.38): icmp_seq=5 ttl=56 time=11.7 ms
64 bytes from 14.215.177.38 (14.215.177.38): icmp_seq=6 ttl=56 time=12.8 ms
64 bytes from 14.215.177.38 (14.215.177.38): icmp_seq=7 ttl=56 time=17.6 ms
64 bytes from 14.215.177.38 (14.215.177.38): icmp_seq=8 ttl=56 time=12.7 ms
64 bytes from 14.215.177.38 (14.215.177.38): icmp_seq=9 ttl=56 time=12.2 ms
64 bytes from 14.215.177.38 (14.215.177.38): icmp_seq=10 ttl=56 time=12.1 ms
--- www.baidu.com ping statistics ---
10 packets transmitted, 10 received, 0% packet loss, time 9078ms
rtt min/avg/max/mdev = 11.782/12.942/17.696/1.644 ms
[yiibai@localhost ~]$
說明: ping 百度(www.baidu.com) 10 次后自動退出。
命令:
ping -c 10 -i 0.5 www.yiibai.com
輸出:
[yiibai@localhost ~]$ ping -c 10 -i 0.5 www.yiibai.com
PING www.yiibai.com (112.124.103.85) 56(84) bytes of data.
64 bytes from 112.124.103.85 (112.124.103.85): icmp_seq=1 ttl=55 time=45.7 ms
64 bytes from 112.124.103.85 (112.124.103.85): icmp_seq=2 ttl=55 time=45.6 ms
64 bytes from 112.124.103.85 (112.124.103.85): icmp_seq=3 ttl=55 time=46.1 ms
64 bytes from 112.124.103.85 (112.124.103.85): icmp_seq=4 ttl=55 time=45.4 ms
64 bytes from 112.124.103.85 (112.124.103.85): icmp_seq=5 ttl=55 time=45.8 ms
64 bytes from 112.124.103.85 (112.124.103.85): icmp_seq=6 ttl=55 time=46.1 ms
64 bytes from 112.124.103.85 (112.124.103.85): icmp_seq=7 ttl=55 time=46.1 ms
64 bytes from 112.124.103.85 (112.124.103.85): icmp_seq=8 ttl=55 time=45.3 ms
64 bytes from 112.124.103.85 (112.124.103.85): icmp_seq=9 ttl=55 time=45.3 ms
64 bytes from 112.124.103.85 (112.124.103.85): icmp_seq=10 ttl=55 time=45.5 ms
--- www.yiibai.com ping statistics ---
10 packets transmitted, 10 received, 0% packet loss, time 4531ms
rtt min/avg/max/mdev = 45.301/45.729/46.187/0.339 ms
[yiibai@localhost ~]$
說明: 每隔 0.5 秒的時間間隔,ping www.yiibai.com ,到達 10 次數(shù)后退出。
命令:
ping -c 5 www.yiibai.com
輸出:
[yiibai@localhost ~]$ ping -c 5 www.yiibai.com
PING www.yiibai.com (112.124.103.85) 56(84) bytes of data.
64 bytes from 112.124.103.85 (112.124.103.85): icmp_seq=1 ttl=55 time=45.6 ms
64 bytes from 112.124.103.85 (112.124.103.85): icmp_seq=2 ttl=55 time=45.9 ms
64 bytes from 112.124.103.85 (112.124.103.85): icmp_seq=3 ttl=55 time=46.1 ms
64 bytes from 112.124.103.85 (112.124.103.85): icmp_seq=4 ttl=55 time=45.3 ms
64 bytes from 112.124.103.85 (112.124.103.85): icmp_seq=5 ttl=55 time=46.1 ms
--- www.yiibai.com ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4017ms
rtt min/avg/max/mdev = 45.332/45.848/46.166/0.413 ms
[yiibai@localhost ~]$ ping -c 5 www.studyoracle.cn
PING www.studyoracle.cn (123.57.223.216) 56(84) bytes of data.
64 bytes from 123.57.223.216 (123.57.223.216): icmp_seq=1 ttl=53 time=54.3 ms
64 bytes from 123.57.223.216 (123.57.223.216): icmp_seq=2 ttl=53 time=54.1 ms
64 bytes from 123.57.223.216 (123.57.223.216): icmp_seq=3 ttl=53 time=53.9 ms
64 bytes from 123.57.223.216 (123.57.223.216): icmp_seq=4 ttl=53 time=54.4 ms
64 bytes from 123.57.223.216 (123.57.223.216): icmp_seq=5 ttl=53 time=54.0 ms
--- www.studyoracle.cn ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4034ms
rtt min/avg/max/mdev = 53.981/54.184/54.438/0.232 ms
[yiibai@localhost ~]$
命令:
ping -i 3 -s 1024 -t 255 192.168.0.5
輸出:
[yiibai@localhost ~]$ ping -i 3 -s 1024 -t 255 192.168.0.5
PING 192.168.0.5 (192.168.0.5) 1024(1052) bytes of data.
1032 bytes from 192.168.0.5: icmp_seq=1 ttl=64 time=0.644 ms
1032 bytes from 192.168.0.5: icmp_seq=2 ttl=64 time=1.36 ms
1032 bytes from 192.168.0.5: icmp_seq=3 ttl=64 time=0.377 ms
1032 bytes from 192.168.0.5: icmp_seq=4 ttl=64 time=1.45 ms
1032 bytes from 192.168.0.5: icmp_seq=5 ttl=64 time=1.46 ms
1032 bytes from 192.168.0.5: icmp_seq=6 ttl=64 time=1.45 ms
^C
--- 192.168.0.5 ping statistics ---
6 packets transmitted, 6 received, 0% packet loss, time 15038ms
rtt min/avg/max/mdev = 0.377/1.125/1.468/0.444 ms
[yiibai@localhost ~]$
說明:-i 3 發(fā)送周期為 3 秒, -s 設(shè)置發(fā)送包的大小為1024, -t 設(shè)置TTL值為 255。