Liunx prohibit Ping explain the different usage of traceroute

Linux Virtual machine can Ping The destination address , But you can't traceroute, Only the gateway .

reason ：windows Of tracert The default is to go ICMP agreement , and linux Of traceroute The default is to go UDP agreement , If between two points UDP connection By any firewall Block out , that traceroute No way. .

resolvent ：traceroute -I Add I Use ICMP agreement

Linux Systematic ping Command is a common network command , It is usually used to test connectivity with the target host , We often say “ping Let's have a look at some machine , See if it's on ”、 When you can't open a web page, you say “ You first ping default gateway 192.168.1.1 try ”. It sends ICMP ECHO_REQUEST Packet to network host （send ICMP ECHO_REQUEST to network hosts）, And show the response , In this way, we can determine whether the target host is accessible according to the information it outputs （ But it's not absolute ）. Some servers in order to prevent passing ping Detected , Disabled through firewall ping Or disable... In kernel parameters ping, This way, we can't go through ping Determine if the host is still on .

linux Under the ping and windows Under the ping There is a slight difference ,linux Next ping Will not automatically terminate , Need to press ctrl+c Terminate or use parameters -c Specify the number of responses required to complete .

1. Command format ：

ping [ Parameters ] [ Host name or IP Address ]

2. Command function ：

ping The command is used for ： Determine the status of the network and each external host ; Track and isolate hardware and software issues ; test 、 Evaluate and manage the network . If the host is running and connected to the Internet , It responds to the echo signal . Each echo request contains an Internet Protocol （IP） and ICMP head , Followed by one tim structure , And enough bytes to fill in this packet . The default is to send the echo request continuously until the interrupt signal is received （Ctrl-C）.

ping The command sends a datagram per second and prints a line of output for each received response .ping Command to calculate signal round-trip time and ( Information ) Packet loss statistics , And show a brief summary after it's done .ping Command timed out in program or when received SIGINT End of signal .Host Parameter is either a valid host name or Internet address .

3. Command parameter ：

-d Use Socket Of SO_DEBUG function .

-f Limit detection . Send a large number of network packets to a machine quickly , Look at its response .

-n Output only values .

-q Do not display any information about the packets sent , Show only the final result .

-r Ignore the ordinary Routing Table, Send the packet directly to the remote host . Usually check whether there is a problem with the network interface of the machine .

-R Record the routing process .

-v Display the execution process of the instruction in detail .

-c number ： Stop... After sending a specified number of packets .

-i Number of seconds ： Set the interval of a few seconds to send a network packet to a machine , The default is send once a second .

-I Network interface ： Use the specified network interface to send out packets .

-l Load ahead ： Set before sending the required information , Packets sent first .

-p Template Styles ： Set the template style to fill the packet .

-s Number of bytes ： Specifies the number of bytes of data sent , The default is 56, add 8 Bytes of ICMP head , Is the total 64ICMP Data bytes .

-t Survival value ： Set the survival value TTL Size .

4. Using examples ：

example 1：ping The general situation of

command ：

ping 192.168.120.205

Output ：

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[[email protected] ~]# ping 192.168.120.205
PING 192.168.120.205 (192.168.120.205) 56(84) bytes of data.
64 bytes from 192.168.120.205: icmp_seq=1 ttl=64 time=0.720 ms
64 bytes from 192.168.120.205: icmp_seq=2 ttl=64 time=0.181 ms
64 bytes from 192.168.120.205: icmp_seq=3 ttl=64 time=0.191 ms
64 bytes from 192.168.120.205: icmp_seq=4 ttl=64 time=0.188 ms
64 bytes from 192.168.120.205: icmp_seq=5 ttl=64 time=0.189 ms

— 192.168.120.205 ping statistics —
5 packets transmitted, 5 received, 0% packet loss, time 4000ms
rtt min/avg/max/mdev = 0.181/0.293/0.720/0.214 ms
[[email protected] ~]#
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example 2：ping The impassable situation

command ：

ping 192.168.120.202

Output ：

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[[email protected] ~]# ping 192.168.120.202
PING 192.168.120.202 (192.168.120.202) 56(84) bytes of data.
From 192.168.120.204 icmp_seq=1 Destination Host Unreachable
From 192.168.120.204 icmp_seq=2 Destination Host Unreachable
From 192.168.120.204 icmp_seq=3 Destination Host Unreachable
From 192.168.120.204 icmp_seq=4 Destination Host Unreachable
From 192.168.120.204 icmp_seq=5 Destination Host Unreachable
From 192.168.120.204 icmp_seq=6 Destination Host Unreachable

— 192.168.120.202 ping statistics —
8 packets transmitted, 0 received, +6 errors, 100% packet loss, time 7005ms
, pipe 4
[[email protected] ~]#
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example 3：ping gateway

command ：

ping -b 192.168.120.1

Output ：

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[[email protected] ~]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.120.0 * 255.255.255.0 U 0 0 0 eth0
192.168.0.0 192.168.120.1 255.255.0.0 UG 0 0 0 eth0
10.0.0.0 192.168.120.1 255.0.0.0 UG 0 0 0 eth0
default 192.168.120.240 0.0.0.0 UG 0 0 0 eth0
[[email protected] ~]# ping -b 192.168.120.1
PING 192.168.120.1 (192.168.120.1) 56(84) bytes of data.
64 bytes from 192.168.120.1: icmp_seq=1 ttl=255 time=2.02 ms
64 bytes from 192.168.120.1: icmp_seq=2 ttl=255 time=1.83 ms
64 bytes from 192.168.120.1: icmp_seq=3 ttl=255 time=1.68 ms
64 bytes from 192.168.120.1: icmp_seq=4 ttl=255 time=1.98 ms
64 bytes from 192.168.120.1: icmp_seq=5 ttl=255 time=1.88 ms

— 192.168.120.1 ping statistics —
5 packets transmitted, 5 received, 0% packet loss, time 4000ms
rtt min/avg/max/mdev = 1.682/1.880/2.020/0.129 ms
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example 4：ping Number of times

command ：

ping -c 10 192.168.120.206

Output ：

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[[email protected] ~]# ping -c 10 192.168.120.206
PING 192.168.120.206 (192.168.120.206) 56(84) bytes of data.
64 bytes from 192.168.120.206: icmp_seq=1 ttl=64 time=1.25 ms
64 bytes from 192.168.120.206: icmp_seq=2 ttl=64 time=0.260 ms
64 bytes from 192.168.120.206: icmp_seq=3 ttl=64 time=0.242 ms
64 bytes from 192.168.120.206: icmp_seq=4 ttl=64 time=0.271 ms
64 bytes from 192.168.120.206: icmp_seq=5 ttl=64 time=0.274 ms
64 bytes from 192.168.120.206: icmp_seq=6 ttl=64 time=0.295 ms
64 bytes from 192.168.120.206: icmp_seq=7 ttl=64 time=0.269 ms
64 bytes from 192.168.120.206: icmp_seq=8 ttl=64 time=0.270 ms
64 bytes from 192.168.120.206: icmp_seq=9 ttl=64 time=0.253 ms
64 bytes from 192.168.120.206: icmp_seq=10 ttl=64 time=0.289 ms

— 192.168.120.206 ping statistics —
10 packets transmitted, 10 received, 0% packet loss, time 9000ms
rtt min/avg/max/mdev = 0.242/0.367/1.251/0.295 ms
[[email protected] ~]#
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example 5： Limited by time intervals and times ping

command ：

ping -c 10 -i 0.5 192.168.120.206

Output ：

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[[email protected] ~]# ping -c 10 -i 0.5 192.168.120.206
PING 192.168.120.206 (192.168.120.206) 56(84) bytes of data.
64 bytes from 192.168.120.206: icmp_seq=1 ttl=64 time=1.24 ms
64 bytes from 192.168.120.206: icmp_seq=2 ttl=64 time=0.235 ms
64 bytes from 192.168.120.206: icmp_seq=3 ttl=64 time=0.244 ms
64 bytes from 192.168.120.206: icmp_seq=4 ttl=64 time=0.300 ms
64 bytes from 192.168.120.206: icmp_seq=5 ttl=64 time=0.255 ms
64 bytes from 192.168.120.206: icmp_seq=6 ttl=64 time=0.264 ms
64 bytes from 192.168.120.206: icmp_seq=7 ttl=64 time=0.263 ms
64 bytes from 192.168.120.206: icmp_seq=8 ttl=64 time=0.331 ms
64 bytes from 192.168.120.206: icmp_seq=9 ttl=64 time=0.247 ms
64 bytes from 192.168.120.206: icmp_seq=10 ttl=64 time=0.244 ms

— 192.168.120.206 ping statistics —
10 packets transmitted, 10 received, 0% packet loss, time 4499ms
rtt min/avg/max/mdev = 0.235/0.362/1.241/0.294 ms
[[email protected] ~]# ping -c 10 -i 0.01 192.168.120.206
PING 192.168.120.206 (192.168.120.206) 56(84) bytes of data.
64 bytes from 192.168.120.206: icmp_seq=1 ttl=64 time=0.244 ms
64 bytes from 192.168.120.206: icmp_seq=2 ttl=64 time=0.195 ms
64 bytes from 192.168.120.206: icmp_seq=3 ttl=64 time=0.219 ms
64 bytes from 192.168.120.206: icmp_seq=4 ttl=64 time=0.204 ms
64 bytes from 192.168.120.206: icmp_seq=5 ttl=64 time=3.56 ms
64 bytes from 192.168.120.206: icmp_seq=6 ttl=64 time=1.93 ms
64 bytes from 192.168.120.206: icmp_seq=7 ttl=64 time=0.193 ms
64 bytes from 192.168.120.206: icmp_seq=8 ttl=64 time=0.193 ms
64 bytes from 192.168.120.206: icmp_seq=9 ttl=64 time=0.202 ms
64 bytes from 192.168.120.206: icmp_seq=10 ttl=64 time=0.211 ms

— 192.168.120.206 ping statistics —
10 packets transmitted, 10 received, 0% packet loss, time 90ms
rtt min/avg/max/mdev = 0.193/0.716/3.564/1.080 ms
[[email protected] ~]#
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example 6： By domain name ping Sites on the public network

command ：

ping -c 5 www.58.com

Output ：

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peida-VirtualBox ~ # ping -c 5 www.58.com
PING www.58.com (211.151.111.30) 56(84) bytes of data.
64 bytes from 211.151.111.30: icmp_req=1 ttl=49 time=14.7 ms
64 bytes from 211.151.111.30: icmp_req=2 ttl=49 time=16.4 ms
64 bytes from 211.151.111.30: icmp_req=3 ttl=49 time=15.2 ms
64 bytes from 211.151.111.30: icmp_req=4 ttl=49 time=14.6 ms
64 bytes from 211.151.111.30: icmp_req=5 ttl=49 time=19.9 ms

— www.58.com ping statistics —
5 packets transmitted, 5 received, 0% packet loss, time 20101ms
rtt min/avg/max/mdev = 14.618/16.192/19.917/1.965 ms
peida-VirtualBox ~ #
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explain ：

example 7： Multi parameter usage

command ：

ping -i 3 -s 1024 -t 255 192.168.120.206

Output ：

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[[email protected] ~]# ping -i 3 -s 1024 -t 255 192.168.120.206
PING 192.168.120.206 (192.168.120.206) 1024(1052) bytes of data.
1032 bytes from 192.168.120.206: icmp_seq=1 ttl=64 time=1.99 ms
1032 bytes from 192.168.120.206: icmp_seq=2 ttl=64 time=0.694 ms
1032 bytes from 192.168.120.206: icmp_seq=3 ttl=64 time=0.300 ms
1032 bytes from 192.168.120.206: icmp_seq=4 ttl=64 time=0.481 ms
1032 bytes from 192.168.120.206: icmp_seq=5 ttl=64 time=0.415 ms
1032 bytes from 192.168.120.206: icmp_seq=6 ttl=64 time=0.600 ms
1032 bytes from 192.168.120.206: icmp_seq=7 ttl=64 time=0.411 ms
1032 bytes from 192.168.120.206: icmp_seq=8 ttl=64 time=0.281 ms
1032 bytes from 192.168.120.206: icmp_seq=9 ttl=64 time=0.318 ms
1032 bytes from 192.168.120.206: icmp_seq=10 ttl=64 time=0.362 ms
1032 bytes from 192.168.120.206: icmp_seq=11 ttl=64 time=0.408 ms
1032 bytes from 192.168.120.206: icmp_seq=12 ttl=64 time=0.445 ms
1032 bytes from 192.168.120.206: icmp_seq=13 ttl=64 time=0.397 ms
1032 bytes from 192.168.120.206: icmp_seq=14 ttl=64 time=0.406 ms
1032 bytes from 192.168.120.206: icmp_seq=15 ttl=64 time=0.458 ms

— 192.168.120.206 ping statistics —
15 packets transmitted, 15 received, 0% packet loss, time 41999ms
rtt min/avg/max/mdev = 0.281/0.531/1.993/0.404 ms
[[email protected] ~]#
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explain ：

-i 3 The sending cycle is 3 second -s Set the sending packet size to 1024 -t Set up TTL The value is 255

in the majority of cases , As a network engineer or system administrator, I will work in UNIX Under the host system , Execute the command line directly ：
Traceroute hostname
And in the Windows Under the system is execution Tracert The order of ：
Tracert hostname
For example, it is used in Beijing windows NT host （ Already with Beijing 163 After establishing a point-to-point connection ）
Use NT In the system Tracert command ：( User available ： Start -> function , Input "command" Call out command Window use this command ）

C:>tracert www.yahoo.com

Parameter description ：

tracert [-d] [-h maximum_hops] [-j computer-list] [-w timeout] target_name

Parameters
-d
Specifies that the address is not resolved for the computer name .
-h maximum_hops
Specifies the maximum number of hops to find the target .
-jcomputer-list
Specified in the computer-list Loose source routing in .
-w timeout
Waiting for timeout The number of milliseconds specified for each reply .
target_name
The name of the target computer .

Traceroute Command parameters for ：

Traceroute The usage of is : Traceroute [options] data size

[options] There are :

Traceroute How it works ：
Traceroute The simplest basic usage is ：traceroute hostname

Traceroute The design of the program is to use ICMP And IP header Of TTL（Time To Live） Field （field）. First ,traceroute Send one TTL yes 1 Of IP datagram（ Actually , Every time I send you 3 individual 40 Bytes of package , Include source address , Destination address and time tag of the package ） Destination , When the first router on the path （router） Receiving this datagram when , It will TTL reduce 1. here ,TTL Turn into 0 了 , So the router will put this datagram lose , And send back one 「ICMP time exceeded」 news （ Including hair IP The source address of the package ,IP All contents of the package and router IP Address ）,traceroute After receiving this message , We know that this router exists on this path , next traceroute Send out another TTL yes 2 Of datagram, Find the first 2 Router … traceroute Every time will send out datagram Of TTL Add 1 To find another router , This repetitive action continues until a certain datagram Arrive at the destination . When datagram After arriving at the destination , The host will not send back ICMP time exceeded news , Because it's the destination , that traceroute How to know the destination has arrived ？

Traceroute Sending out UDP datagrams When we get to our destination , What it chooses to deliver port number It's a number that the average app doesn't use （30000 above ）, So when this UDP datagram After arriving at the destination, the host will send back a 「ICMP port unreachable」 The news of , And when traceroute When I received the news , We know that the destination has arrived . therefore traceroute stay Server There is no such thing as Daemon The program .

Traceroute Extract hair ICMP TTL Of the expiration message device IP Address and domain name resolution . Every time ,Traceroute All print out a series of data , Including the domain name of the routing device and IP Address , The time it takes for three bags to go back and forth .

Traceroute There is a fixed time to wait for a response (ICMP TTL Expiration message ). If this time passes , It will print out a series of * No ： On this path , This device can't send out in a given time ICMP TTL Response to expiration message . then ,Traceroute to TTL The counter adds 1, Keep going .