Description of the PING command. Getting to know the Ping command How to stop ping in Linux
Team PING it is perhaps the most used command line network utility. PING is present in all versions of all network-enabled operating systems and is a simple and convenient means of querying a host by name or its IP address.
A special control message protocol is used to exchange service and diagnostic information on the network. ICMP(Internet Control Message Protocol). Team ping allows you to send a control message like echo request(type is 8 and is indicated in the ICMP message header) to the addressed node and interpret the response received from it in a form convenient for analysis. The data field of the sent icmp packet usually contains English characters. In response to such a request, the polled node should send an icmp packet with the same data that was received and the message type echo reply(the type code in the ICMP header is 0) . If there is a problem with icmp messaging, the ping utility will display information to help diagnose the problem.
Command line format:
Ping [-t] [-a] [-n number] [-l size] [-f] [-i TTL] [-v TOS] [-r number] [-s number] [[-j Nodelist] | [-k Nodelist]] [-w timeout] endName
Options:
-t- Continuous sending of packets. Keyboard shortcuts are used to complete and display statistics Ctrl+Break(statistics output and continued), and ctrl+c(output of statistics and completion).
-a- Determination of addresses by hostnames.
-n number- The number of echo requests to send.
-l size- The size of the data field in bytes of the request being sent.
-f- Setting a flag that prohibits packet fragmentation.
-iTTL- Setting the lifetime of the package ("Time To Live" field).
-v TOS- Setting the type of service ("Type Of Service" field).
-r number- Record the route for the specified number of transitions.
-s number- Timestamp for the specified number of transitions.
-j List of Nodes- Free choice of route according to the list of nodes.
-k list of nodes- Rigid route selection based on the list of nodes.
-w timeout- The maximum time to wait for each response in milliseconds.
Examples of using:
ping google.com- echo request to the node with the name google.com with default parameters - the number of packets is 4, the length of the data array = 32 bytes.
ping-6 ya.ru- node ping ya.ru using IPv6 protocol
ping -a 192.168.1.50- perform a ping with the definition of the name of the host node by its address.
ping -s 192.168.0.1computer- node ping computer from source 192.168.0.1. Used when the computer has multiple network interfaces.
ping w 5000- ping with a waiting timeout of 5 seconds (default - 4 seconds).
ping -n 5000 -l 1000 site- node poll website 5000 times, in 1000byte data packets. The allowed maximum data length is 65500.
ping -n 1 -l 3000 -f ya.ru- ping with packet fragmentation prohibited.
ping -n 1-r 3- send 1 echo request per node ya.ru with display of the first 3 transitions along the route.
ping -i 5 ya.ru- ping with time to live TTL=5. If it takes to reach the final node large quantity hops along the route, the router that interrupted the delivery will respond with the message “Exceeded the time to live (TTL) while transmitting the packet.”
Generalized connection diagram of a computer (tablet, laptop home network) with a remote end node can be represented as follows:
The most common network with IP addresses 192.168.1.0 /255.255.255.0 is used as the home network. We are talking about IPv4 - IP protocol version 4, where 4 bytes are used for addressing. IP addresses it is customary to represent as decimal byte values separated by dots. Each device on the network must have its own unique address. In addition to the address, network settings use mask network (subnet mask). The mask has the same presentation format as the address. The combination of address and mask defines the range of addresses that belong to local network- 192.168.1.0-192.168.1.255. The first and last addresses of the range are not assigned to individual network devices because they are used as the network address and broadcast address. Usually the router address is set to 192.168.1.1 or 192.168.1.254. This is not a mandatory standard, but is used quite often in practice. The 1 bits of the mask determine the constant part of the network IP address, and the zero bits are allocated to individual hosts. Meaning 255 is a byte with bits set to one. The netmask serves as a means of determining the range of IP addresses that belong to the local network. Devices with these addresses are reachable locally, without using routing. Routing is a way of exchanging data with network devices that do not belong to a given local network through a special device - router(router, router). Routers are specialized computers with multiple network interfaces and specialized software providing forwarding of IP packets between the sender and the recipient located in different networks. Multiple routers may be involved in this forwarding, depending on the complexity of the route. A home router is the simplest type of router that forwards packets destined for external networks to the next router on the route in the provider's network. The next router checks the reachability of the destination host address locally and either forwards the data to it or passes it on to the next router according to the routing table. This happens until the data reaches the recipient or the packet lifetime expires.
The PING command can be used to diagnose individual hosts:
ping 127.0.0.1 is a ping of the loopback interface. Should run without errors if installed and in working condition network software components.
ping your IP or name- ping to your own address or name. Should complete without errors if all IP protocol software is installed and healthy network adapter.
ping router IP address- must be performed if correct LAN card computer, the cable or wireless connection used to connect to the router is working, and the router itself is working. In addition, the IP settings must be such that the address of the computer and the router belong to the same subnet. This is usually the case when network settings are performed automatically by the router's DHCP server.
ping yandex.ru- poll the node with the name yandex.ru. If the poll ends with an error, then the reason may be not only the lack of communication with the provider's router, but also the inability to determine the host address yandex.ru due to problems with software tools name resolution.
ping 8.8.8.8- poll the host with IP address 8.8.8.8 . If polling by address runs without errors, but polling by name ends with an unknown host message, then the problem is name resolution. The reason may be the inoperability of the provider's DNS server. In this case, you can try changing it in the settings network connection to public DNS servers Google with addresses 8.8.4.4 and 8.8.8.8. Also, the problem can be caused by poor communication quality with the provider, which is accompanied by too long response times and packet drops.
ping -t yandex.ru- perform ping before pressing the CTRL + C combination, When you press CTRL + Break - statistics are issued and the polling of the node continues.
Ping -n 1000 -l 500 192.168.1.1 - ping 1000 times using 500 byte messages. Ping with packets of standard length of 32 bytes can be performed without errors, and with long packets - with errors, which is typical for wireless connections at a low signal level in conditions of intense interference.
Ping -n 1 -r 9 -w 1000 yandex.ru - ping 1 time (key -n 1), give a route for the first 9 hops (-r 9), wait 1 second (1000ms) for a response
As a result of executing this command, the route trace is also displayed:
Packet exchange with yandex.ru with 32 bytes of data:
Response from 87.250.251.11: number of bytes=32 time=36ms TTL=54
Route: 81.56.118.62 ->
81.56.112.1 ->
10.109.11.9 ->
10.109.11.10 ->
195.34.59.105 ->
195.34.52.213 ->
195.34.49.121 ->
195.34.52.213 ->
87.250.239.23
Ping stats for 87.250.251.11:
Packets: Sent = 1, Received = 1, Lost = 0
(0% loss)
Approximate round-trip time in ms:
Minimum = 36ms, Maximum = 36ms, Average = 36ms
AT this example, a chain of 9 routers is built between the sender and receiver of packets. It is necessary to take into account the fact that in the version of the utility ping.exe for Windows, the number of transitions can take a value from 1 to 9. In cases where this value is not enough, the command is used tracert
The lack of an echo response is not always a sign of a problem, because sometimes, for security reasons, some hosts are configured to ignore echo requests sent by PING. An example would be a node microsoft.com and some routers in small ISP networks.
Using PING in batch files.
Often, the PING command is used to delay batch files. The loopback interface is pinged, specifying desired value packet counter specified by the parameter -n. Pings are sent at 1 second intervals, and the response on the loopback interface is almost instantaneous, so the delay will be approximately equal to the counter minus one:
ping -n 11 127.0.0.1- 10 second delay.
The PING command is used in batch files to determine the availability of IP addresses. Since the result of the poll is not reflected in the ERRORLEVEL variable in any way, instead of analyzing it, a search for certain features in the PING standard output data is used. If you look closely at the messages of the ping.exe program when polling an available and inaccessible host, you will notice that they differ significantly
ping 456.0.0.1- ping to a non-existent address
The response to such a command may differ from the specific version of the utility, and may be something like this
Ping failed to locate host 456.0.0.1. Check the hostname and try again.
ping yandex.ru- ping to the address of the yandex.ru node
Reply to ping an available host:
Packet exchange with yandex.ru for 32 bytes:
Response from 87.250.250.11: number of bytes=32 time=10ms TTL=55
Thus, to solve the problem of determining the availability of a node in a batch file, it is enough to analyze the characteristic words in the output of ping.exe in case of a successful response. Most characteristic in this case is the presence of the word TTL. It never occurs when an error occurs and consists of only English characters. To search for "TTL" in the results of ping.exe, it is most convenient to chain its execution with the command to search for a character string FIND.EXE(ping and find pipeline). If the text is found by the FIND command, then the value of the ERRORLEVEL variable will be equal to 0
ping -n 1 COMPUTER | find /I "TTL" > null
if %ERRORLEVEL%==0 goto LIVE
ECHO computer not available
unreachable state routine
...
exit
:LIVE - start of subroutine for processing node availability status
...
...
In a simpler version, you can use the commands:
PING yandex.ru |find "TTL=" && ECHO Yandex pingable- the ECHO command is executed if the ERRORLEVEL value set by FIND is 0, i.e. the node yandex.ru responds to ping.
PING Server64 |find "TTL=" || ECHO Server64 not pingable- The ECHO command is executed if the ERRORLEVEL value set by FIND is not equal to 0, i.e. node Server64 did not respond to ping.
On the Internet, in particular, on forums, in case of a problem with connecting to any node (), it is recommended to check the ping or perform a route trace and thus check the availability of the server.
But what is ping and what is tracing? Ping (ping) is a tool (utility) for checking the integrity of the connection in networks based on TCP / IP. Traceroute (traceroute or tracert command) is a program for determining data routes in TCP/IP networks.
However, it is not always possible to find information on how exactly this check is performed: how to ping or how to make a trace.
Ping check
To check the ping, use the command of the same name ping, which must be entered on the command line. You can start the command line in the following ways:
Windows:
1) Start -> All programs -> Standard -> Command line
2) Start -> Run -> cmd
There are many terminals in this OS, so for these purposes you can use any of those installed on your PC. Usually a standard terminal can be launched with a keyboard shortcut CTRL+ALT+T.
So, to ping a specific server, you need to run the command:
Ping
For example, to ping an address 11.222.33.44 you need to run the command:
Ping 11.222.33.44
Below is an example of the results of pinging one of the IP addresses.
As can be seen from the results, 4 packets of 32 bytes in size were transmitted and received. The exchange time for one packet was 47 milliseconds.
Note that Windows only sends 4 packets by default. In Linux, the packet exchange continues until the user himself stops the process with a keyboard shortcut. CTRL+C. To run ping in the same way on Windows, you need to use the parameter -t. For example:
Ping -t 11.222.33.44
Stopping the exchange of packets is performed by the same key combination - CTRL+C.
Setting the number of packets to send
To set maximum amount packets to be sent, you must use the following command:
Windows:
Ping-n<число_пакетов>
For example:
Ping -n 5 11.22.33.44
Ping -c<число_пакетов>
For example:
Ping -c 5 11.22.33.44
Change the size of sent packets
To ping using packets of a certain size (in bytes), you must use the following command:
Windows:
Ping -l<размер_пакетов>
For example:
Ping -l 64 11.22.33.44
Ping -s<размер_пакетов>
For example:
Ping -s 64 11.22.33.44
In this case, packets of 64 bytes in size were sent.
A traceroute can show the rate at which packets travel between routers that connect the requesting PC to the destination server.
The following command is used to run a trace:
Windows:
Tracert
For example:
Tracert wikipedia.org
traceroute
For example:
Traceroute wikipedia.org
It is worth noting that, by default, tracing also performs a DNS query to resolve the IP address in Domain name for each passing router. This option can be disabled, thus reducing the time it takes to get trace results.
To enable this option, you must use the following command type:
Windows:
Tracert -d
Traceroute -n
I already wrote about , today I would like to focus your attention on the ping command. System administrators use the Ping command most often, although its potential is quite limited. In this article I will tell you how you can use the ping command, and what tasks it will help you solve.
Let's see what the Ping program can do, to do this, click start => run => type cmd => click OK => type the command in the black window
ping /? => press enter.
You will see a list of commands that you can execute using the Ping program.
Ping [-t] [-a] [-n<число>][-l<размер>][-f][-i
Let's take a look at some of them.
Practical use:
The t key is used when it is necessary to ping a resource for a long time so as not to enter the command every time:
Ping site
can be entered like this:
Ping 27susday.ru -t
and the process can only be stopped manually by pressing ctrl+c
The i key is needed to set the lifetime of the sent packet, by default 128. You send a packet and it starts rummaging through remote nodes, after passing the node, one is taken away, and so on until there is zero. Then the package is destroyed, and displays a notification for you.
The w– key is needed to increase the response time from the resource you are accessing. There are times when you send a ping to a node, and it gives you a message that the specified node is not available, so you think that the node is down. The conclusion is correct, but not always. It happens that it is available, only now it is overloaded and does not have time to answer you, in order to avoid this, the w key is put.
It happens that the remote node seems to be working, i.e. you can go to it, you are one hundred percent sure of its performance, but it does not respond to ping, at least set a delay using the w key. This is explained by System Administrator, put a firewall and forbade answering ICMP packets. This is done so that it is impossible to storm servers that look at the Internet with echo requests. The server will not fall down, but its performance will decrease.
Advice: If you are a novice system administrator, I advise you to close the ICMP port on your servers that you have access to the Internet.
In this article, you learned about the three main keys for the Ping program.
Video tutorial on how to reduce ping in games:
PING is the main command line utility. Windows strings to check connections in networks based on TCP/IP. The PING command, using ICMP echo request messages, verifies an IP-level connection to another computer that supports TCP/IP. After each transmission, a corresponding message with an echo reply is displayed.
Ping is perhaps the most basic TCP/IP command among Windows users, used for troubleshooting and checking the ability to access the Internet.
The Ping command, run without parameters, displays help. Works equally well for everyone Windows versions, including Windows 10.
To check the network, you can also use the commands:
- TRACERT - determines the path to the destination by sending echo messages;
- PATHPING - Provides information about data loss on intermediate nodes.
Syntax Parameters Important PING Command Keys
ping [-t] [-a] [-n count] [-l size] [-f] [-i TTL] [-v type] [-r count] [-s count] [(-j hostlist | - k hostlist)] [-w interval] [target_computername], where
- -t - Sets the ping command to send ping messages to the destination until the command is aborted. To interrupt the command and display statistics, press the CTRL-BREAK combination. To interrupt and exit the ping command, press CTRL-C.
- -a - Sets the reverse name resolution to the destination IP address. If successful, the corresponding node name is displayed.
- -n counter - Sets the number of echo request messages to send. The default is 4.
- -l size - Specifies the length (in bytes) of the data field in sent echo request messages. The default is 32 bytes. Maximum size - 65527.
- -f - Specifies that echo request messages be sent with the "Don" t Fragment" flag in the IP header set to 1. Echo request messages are not fragmented by routers on their way to their destination. This setting is useful for troubleshooting problems with the maximum block data for the channel (Maximum Transmission Unit).
- -i TTL - Sets the value of the TTL field in the IP header for outgoing echo request messages. The default is the host's default TTL value. For Windows nodes XP, this value is usually 128. The maximum TTL value is 255.
- -v type - Sets the value of the Type of Service (TOS) field in the IP header for outgoing echo request messages. By default, this value is 0. type is a decimal value between 0 and 255.
- -r counter - Sets the Record Route option in the IP header to record the path along which the echo request message and its corresponding echo reply message traverse. Each hop in the path uses a route entry parameter. If possible, the counter value is set equal to or greater than the number of hops between source and destination. The counter parameter has a value from 1 to 9.
- -s counter - Specifies the Internet Timestamp option in the IP header to record the arrival time of the echo request message and its corresponding echo reply message for each hop. The counter parameter has a value from 1 to 4.
- -j nodelist - Indicates echo request messages to use the loose routing option in the IP header with the set of intermediate destinations specified in host_list. With free routing, successive intermediate destinations can be separated by one or more routers. The maximum number of addresses or names in a host list is 9. A host list is a set of IP addresses (in dotted decimal notation) separated by spaces.
- -k hostlist - Indicates echo request messages to use the strict routing option in the IP header with the set of intermediate destinations specified in hostlist. With strict routing, the next intermediate destination must be directly reachable (it must be a neighbor on the router interface). The maximum number of addresses or names in a host list is 9. A host list is a set of IP addresses (in dotted decimal notation) separated by spaces.
- -w interval - Specifies, in milliseconds, the time to wait to receive an echo reply message that matches the echo request message. If the echo reply message is not received within the specified interval, then a "Request timed out" error message is issued. The default interval is 4000 (4 seconds).
- target_computer_name - Specifies a destination identified by an IP address or hostname.
Examples of using the PING command
- To display help at the command prompt, type: ping /?;
- To manually test the connection of the ya.ru address before aborting, enter: ping ya.ru -t;
- To send an ICMP echo request message to destination 192.168.1.1 and match it with its hostname, type: ping -a 192.168.1.1;
- To send a ping request message to 10.0.99.221 ten ping request messages, each with a data field of 1000 bytes, type: ping -n 10 -l 1000 10.0.99.221;
- To send a ping request message to destination 10.0.99.221 and record a route for 4 hops, enter: ping -r 4 10.0.99.221;
- To send a ping request message to 10.0.99.221 and set free routing for destinations 10.12.0.1-10.29.3.1-10.1.44.1, enter: ping -j 10.12.0.1 10.29.3.1 10.1.44.1 10.0.99.221.
Video - How to use the PING utility
“Oh, help, everything is gone!” - if your inner voice reacts to a disconnection with the server like this, this material is definitely for you. :) Of course, for our part, we do our best every day so that nothing interferes with your work in the cloud, but if there is a force majeure, we will deal with it. And in order to quickly navigate the situation and understand on whose side the error is, here is the minimum task for you - during the break, first of all, trace the route and ping intermediate nodes. How to do all this, now we will tell.
Trace route
During tracing, data packets are sent between local computer and server. This helps to trace the path of the request to the server and determine at what stage the break occurs. Tracing is pretty easy.
1. Run cmd command: Windows+R > write down cmd > ok.
tracert X.X.X.X(where X.X.X.X is the server IP address or domain) and click Enter.
In the example, we made a trace for google.com.
tracert google.com
It turned out like this:
1 2 1 ms 1 ms 1 ms 193.151.89.254
3 5 ms 4 5 1 ms 6 1 ms 7 1 ms 3 ms 1 ms bearline-ic-324086-ffm-b4.c.telia.net
8 1ms 1ms 1ms 108.170.251.129
9 13ms 13ms 15ms 66.249.94.135
10 13 ms 13 ms 13 ms fra15s12-in-f46.1e100.net
As you can see, our packets have overcome ten (there may be less or more) nodes, and successfully overcome them. AT otherwise, if the packets “stumbled” on one of the nodes, on it (and the nodes following it) we would see:
* * * Timed out request.
But even in this case, it is not yet time for conclusions - this entry can mean both packet loss and the fact that the host is simply closed by security settings. Sometimes providers specifically configure nodes so that they do not respond to trace packets in order to reduce the load. To find out exactly whether a break really occurs, and if so, where exactly, you need to ping each of the nodes. When tracing, we got the IP of each of them, which means we can move on to ping.
Ping smart hosts
Ping is designed to check the integrity and quality of connections. It's also easy to do. In this case, you need to start ping to all intermediate nodes in separate windows. So right at the time of the connection break, it will be visible on which node packet losses occur and how long these breaks are.
On Windows, by default, only four packets are transmitted, which is not enough if the problem is transient. Therefore, it is necessary to remove this limitation with the parameter -t(to stop the exchange of packets later, press CTRL+C).
Now in order.
1. Run cmd command: Windows+R > write down cmd > ok.
2. In the command line that opens, type ping -t X.X.X.X(where X.X.X.X is the address of one of the intermediate nodes that we learned during the trace) and click Enter.
In our case, when tracing, we identified ten nodes, which means that we need to ping ten times in ten separate windows.
Healthy!
If you need to constantly monitor the quality of the connection, for Windows you can use convenient program PingPlotter.
So, we ping - in ten separate windows of the command line, we enter commands with the IP addresses of the nodes that we identified during the trace. In our case, there will be such commands:
ping -t 10.1.1.1
ping -t 193.151.89.254
ping -t 85.195.75.129
ping -t 213.248.79.29
ping -t 62.115.139.50
ping -t 62.115.120.8
ping -t 62.115.153.215
ping -t 108.170.251.129
ping -t 66.249.94.135
ping -t 216.58.208.46
If in any of the windows you see from the very first seconds “Wait interval exceeded”, do not rush to shout: “Gotcha!”. If the following nodes ping normally, then this one is simply closed by the settings. In our case, for example, the penultimate node (66.249.94.135) immediately says that the interval has been exceeded, but there are no problems with the ping of the tenth node.
Which side is wrong?
So, the break happened again. But this time, running a ping of intermediate nodes will help to "expose" the culprit. Everything is simple here - from which node you started to give out “waiting interval exceeded”, that is the weak link.
Who is to blame is clear, now you need to understand what to do in specific situations.
1. The last node. If the last host pinged normally at first (some Windows machines don't respond to pings at all, this is set in the firewall settings)...
... and after the break, it began to show “Wait interval exceeded”, the break occurs on your server.
In this case, go to the control panel, launch the console and log into the operating system to find out why the server is not working. If the operating system appears to be hung, restart the server.
2. Any nodes except the last one. In this case, contact the technical support of both the cloud and the Internet provider at the same time. At the same time, be sure to indicate how the route trace initially looked like, and make a list of nodes indicating which of them ping was interrupted during the break and which were not. Be careful, this important information, make no mistake.
3. All nodes at the same time. If all the ping windows started showing "Timeout exceeded", the problem is with your computer or the network it is connected to.
Bonus!
Well, to make you feel completely comfortable, we have selected utilities with which you can trace and ping intermediate nodes in one simple movement without launching fifteen different windows.
For the Windows OS family, this optimization is carried out by the utility winmtr. It does not need installation and is ready for use immediately after unpacking from the archive.
In field Host specify the destination server with which the connection will be checked, and click Start:
In our example, the route trace and all intermediate nodes are visible. At the same time, ICMP packets are sent to each of them, by which you can determine the quality of the connection.
Actually, this is the main advantage of the utility - its output is constantly updated, this allows you to collect statistics, track averages, trends and any changes in network quality.
Since we are checking the connection to the server, we are interested in the columns Saint(packages sent) and Recv(packages received). If the values in these columns do not match, then the quality of communication with the host has deteriorated. What to do? Contact the appropriate technical support.
The Loss column will help you view the dynamics of losses as a percentage.
The utility also allows you to copy text in convenient formats ( .txt and .html) to clipboard ( Copy to clipboard) or in separate file (Export).
Double clicking on an intermediate node will provide additional information about it.
It is important to know!
To detail the problem, technical support specialists can request additional pings with special settings. To do this, just enter them in the box Options, which will allow you to specify:
- Interval (sec)– data update time in seconds.
- Max host in LRU list– maximum number of hosts (or IP addresses, if the option Resolve names) to the end point.
- Ping size (bytes) – ICMP packet size.
- Resolve names– the ability to convert an IP address to a hostname.
What about Linuxoids?
For Linux operating systems, the utility is simply called MTR. If it is not in your operating system, you can install it in one of the following ways:
Debian/Ubuntu/Mint:
$ apt-get install mtr
CentOS/RedHat/Fedora:
$ yum install mtr
MTR has the same functionality as Winmtr, as well as a similar GUI. You can run the utility with the command:
where X.X.X.X is the destination server's IP address or hostname.
In this case, the following columns are of interest:
- Loss % - percentage lost packets between the sending computer and intermediate hosts.
- SNT is the total number of packets sent.
As soon as something is lost somewhere, the utility signals us about it by coloring the node red and calculating the percentage of losses.
Separately, we note the possibility of running the utility in text (console) mode. To do this, just add the -t or --curses option:
mtr --curses site
Let's look at a few more important MTR options that can be extremely useful in the process of network diagnostics.
R or --report
Starts a report mode in which the MTR will process the specified number of cycles (specified by the -c option) and then display statistics and exit automatically. This mode is useful for collecting network quality statistics.
C COUNT or --report-cycles COUNT
Allows you to set the number of cycles after which the MTR will shut down.
P BYTES or --psize BYTES
Sets the packet size in bytes.
I SECONDS or --interval SECONDS
Sets the interval between sent packets.
N or --no-dns
Allows not to use DNS, displays host IP addresses.
A X.X.X.X or --address X.X.X.X
Allows you to specify the interface address of the computer from which ICMP requests will be sent.
Total
Of course, the commands in the console give a more accurate result, since they fix even single packet losses (short breaks), but Winmtr and MTR are compact and more convenient to use. And what to choose, it's up to you. :)
Here, in fact, everyone who is to blame - found out what to do - too. :) We hope the material was useful to you, and if you still have additional near-cloud questions, please contact us for a competent one.
