How to check your network connection. Commands to check and correct network settings Use network utilities

All tips

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Diagnostic commands:

*Executed in a previously opened “command line” window. (Start -> All Programs -> Accessories -> Command Prompt)
For Windows Vista/7: Win+R ===> cmd ===> Enter
For Windows NT/2000/XP/VISTA: "Start" - "Run" - "cmd"
For Windows 95/98: "Start" - "Run" - "command".

Copying text: right-click on this window - “edit” - “select” and “edit” - “copy”.

ipconfig /all
nslookup
ping [host address (for example, ya.ru) ] [-n 20]
pathping [host address]
tracert [host address]

ipconfig /all shows network interface settings.
Everything that is indicated there must be checked with the user manual (if the manual is old, then check it with the data that was issued by technical support). See how to set up a connection on the website.

ping [-t] shows the response time from the specified host. Large delays can indirectly serve as an indicator of a slow resource (loaded channel, weak resource hardware, and similar problems). The [-t] key is used to execute a command before the user interrupts it by pressing "Ctrl+C". By default, without this key, ping will only be executed four times, which is not always enough.

pathping Shows the response time and the number of missing packets along the entire route to the host.

tracert
To graphically display problems, you can download the PingPlotter program from the local network

nslookup
Check DNS operation.

Check algorithm: Error "Network cable is not connected"

1. Check the cable connection in the network card
2. Check the integrity of the cable to the shield.
3. Call Tech. support.

The network cable is connected, but there are no incoming packets.

1. Check the cable connection in the network card (you can remove and insert the cable into the socket).
2. Disable all firewalls (firewalls), if you have them.
3. Ping the gateway (take the address from the connection settings or from the connection information in the control panel).
4. Call Tech. support.

The network cable is connected, there are incoming packets, but you cannot access internal services:

1. Disable all firewalls (firewalls), if you have them.
2. Check the operation of DNS (nslookup).
3. Check connection with these servers (ping)
4. Check connection with central servers. (ping online.vo, ping 192.168.0.250, ping_your_gateway_address)
5. Check your browser settings
5.1. Internet Explorer -> "Tools" menu -> "Internet Options" -> "Connection" -> "Network Settings" -> check if the "use proxy server" checkbox is disabled
6. Call Tech. support.

DNS check:

The nslookup server command should return the IP address of this server. For example, the command "nslookup vo47.ru" should return the address "193.106.108.68"

Diagnostic commands

Team	Purpose	Launch format	Example
ipconfig	Shows network interface settings	ipconfig /all
netstat	Shows the route table	netstat -nr
nslookup	Contacts the DNS server (if not specified, it is taken from the Windows settings) to convert the computer's DNS name to its IP address or vice versa	nslookup DNS_name_or_IP_address IP_address of DNS_server	nslookup vo47.ru nslookup ya.ru 193.106.108.67
ping	Checks the availability of communication with another computer and the speed of response. It is not a means of measuring connection speed.	ping DNS name_or_IP address	ping www.vo47.ru ping 193.106.108.97
tracert	Same as ping, but with information output for all intermediate nodes	tracert -d DNS name_or_IP address	tracert -d cs47.ru
pathping	Same as tracert, but in more detail and indicating the percentage of losses	pathping DNS name_or_IP address	pathping vk.com

At first glance, it may seem that a computer, being connected to a global network, uses only a few connections, but in fact there can be dozens of such connection points.

If you want to see this for yourself, use the special TCPView utility designed to monitor all connections existing in the system (connection monitoring) using the TCP and UDP protocols.

The TCPView utility is authored by renowned Windows security specialist Mark Russinovich and is part of the Sysinternals Suite. It is free, despite the English-language interface, it is very easy to use and does not require installation.

When launched, TCPView monitors connections and displays a list of all processes using TCP and UDP connections.

This displays the main parameters of each connection: process name, protocol, identifier, connection states, remote and local addresses.

The TCP and UDP protocols are the rules by which data exchange occurs within the network. For example, the TCP protocol is very similar to how regular mail works.

Delivery of letters from the sender to the recipient and vice versa is possible only if the correct address is indicated on the envelope.

The same thing happens when transmitting data via the TCP protocol. Any program that uses the Internet has a special identifier and it is called a port number.

Many programs have standard numbers, for example, applications for transferring data via ftp have number 21, anyone who has had to work with will immediately understand what we are talking about.

Connection monitoring

So, thanks to the TCPView utility, you can find out at any moment which application is using the Internet connection, who is connected to you, and what ports are being listened to.

This will allow you to completely control the network activity of any program, including malicious ones, because Trojans, especially, very often use the connection to transfer data.

If you detect a suspicious connection, you can close it or terminate the process completely

When you have an active network connection, you may notice that some of the connection endpoint strings are constantly changing color, like a traffic light. This is done specifically to make it more convenient for the user to track changes.

Thus, newly opened points will be marked in green, those whose status has suddenly changed will be yellow, and closed connection points will be highlighted in red.

All information is updated every second, which is, according to the developer, the most optimal for monitoring connections, but you can change the update speed or even turn it off by selecting in the menu View paragraph Update Speed.

By default, IP address and port number data is displayed in alphabetic characters.

If this seems inconvenient to you, press Ctrl+R and the utility will immediately switch to digital display mode. To view the full path to the process file, double-click on the selected line.

In the properties window that opens, you can view the full path, version of the executable file and, if necessary, terminate the process by clicking on the " button End Process".

This operation, copying data ( Copy), as well as ending the connection without deleting the process ( Close Connection) can be executed from the TCPView context menu, called as usual with the right mouse button. Download the program from official website

For comfortable browsing on the Internet, the speed and stability of the network connection are important.

Sometimes problems arise with your network connection, resulting in files taking a long time to download or web pages not loading. To find out why the problem occurred, check your network connection.

Run built-in diagnostics

Check your network access using the Windows troubleshooter and the macOS wireless diagnostic tool. Select operating system:

Windows 10
Windows 7
macOS

Run the Network Troubleshooter:

Click Start → Control Panel→ Network and Internet → Network and Sharing Center → Troubleshooting → Internet connections.

Follow the instructions on the screen.

Use the program "Wireless diagnostics".

For more information, see Analyze your wireless environment on the Apple Support site.

Use network utilities

Obtain network diagnostic information using Ping, PathPing/Traceroute, and Telnet utilities. Select operating system:

Windows 10
Windows 7
macOS

Ping

PathPing

Telnet

First install the Telnet client:

Other utilities

Run the utility:

Ping

Using the Ping utility, you can check the quality of your network connection. The utility determines the delay time between a request to the server and the response, as well as the loss of data packets. The shorter the round-trip time and the number of lost packets, the faster the web page will open or the movie will load.

To check your network connection:

PathPing

Using the PathPing utility, you can determine at which intermediate network node data packets are delayed or lost.

To check intermediate network nodes:

Telnet

You can use the Telnet utility to check whether your computer has permission to connect to the server.

First, enable the Telnet client. For this:

Now you can check server access:

Other utilities

Select a utility depending on the purpose:

Ipconfig - find out the IP address, subnet mask and other network settings;

Getmac - view network connections, network adapters and their physical addresses;

Tracert - get a chain of nodes through which an IP packet passes.

Run the utility:

Go to the Start menu and type command prompt or cmd.exe in the search bar. Launch the application.

In the window that opens, enter:

ipconfig/all - for Ipconfig;

getmac/v - for Getmac;

tracert<адрес сайта>- for Tracert.

Press Enter.

To copy information, right-click anywhere in the open window and select Select All. Then press Enter.

Copied text can be pasted (Ctrl + V) into a text file or letter.

Setting up a network connection in accordance with all instructions does not guarantee uninterrupted access to the Internet. The reasons why a network stops working are varied and not always obvious. Let's talk about what can cause an Ethernet connection to fail and how to fix it.

Why does the network connection via cable not work in Windows 8?

Hardware-related reasons:

the network cable is damaged or poorly crimped;
the length of the cable segment between network nodes has been exceeded (more than 100 meters);
network devices are not connected correctly;
the network gateway (the device through which the computer connects to the Internet) does not work or is configured incorrectly;
the cable is not connected to the computer’s network card;
the network card is faulty or not installed (driver is missing);
There is a source of electromagnetic interference near a cable, computer or other network device (router, switch).

Reasons related to settings:

Windows network services are not running;
Winsock configuration has been changed (Winsock are Windows structures that control application access to network services);
connection parameters are incorrectly specified;
The network adapter is disabled to save energy;
communication is blocked by incorrect settings of security programs (firewall or Windows firewall);
connection to the network (or only to the Internet) is limited by the administrator;
Windows is infected with malware that blocks access to the Internet.

If the connection is limited for certain applications, for example, only for the browser:

the application accesses the Internet through a proxy server that is unavailable;
the application is blocked by the Windows firewall, firewall, or computer administrator;
Malicious scripts run in the context of the application.

Restoring the cable network

Troubleshooting equipment

If the connection is completely absent, periodically disappears or loses data, start checking with the network cable. Make sure its insulation is intact and there are no kinks. Check the quality of fastening of the connectors.

If you are setting up the connection for the first time, make sure that the cable is crimped correctly (the conductors are connected to the correct contacts of the connector). Below are the crimping diagrams:

to connect a computer to a device (switch or router);
for computer-to-computer connection.

The check is only relevant if you crimped the cable yourself. Cables purchased in a store already with connectors rarely fail.

Next, check whether the network is connected correctly. The Internet connection can be direct (the provider's cable is connected to the computer's network card) or through a gateway (router or other computer). The method of switching and access settings can be found in the technical support of the provider.

When connecting through a router, it is important not to confuse the connection sockets: the provider’s cable is inserted into the “INTERNET” or “WAN” socket, and network cards of computers are connected to the “LAN” sockets.

If there is still no connection, check whether the network driver is installed in Windows.

Open Device Manager - in Winows 8 it is called from the context menu of the Windows (Start) button.

Expand the Network Adapters list and check to see if the Ethernet card is there. If it is identified as an unknown device, go to its manufacturer's website using a different Internet connection, download and install the driver.

After that, open the card properties through the context menu in Device Manager

and make sure it works fine.

Next, open the “Power Management” tab and uncheck the “Allow shutdown to save energy” option, otherwise the connection will be interrupted.

If, after installing the network driver, the connection is still limited, check whether there are any devices that create interference near the computer, router, or the place where the network cable is laid: cordless phones, powerful power lines, microwave ovens. Try to move your network equipment away from such places.

Checking Windows network settings

Using the network diagnostic tool

The Troubleshooting tool allows you to identify and eliminate the causes of various network failures in Winows 8. To launch it, click on the “Network” icon in the system tray and select the item of the same name.

If the problem is not automatically resolved, the diagnostic tool will tell you what caused the problem.

In this case, the cause will have to be sought and corrected in other ways.

Starting services

If your Internet connection is limited or absent, it may be due to a failure of Windows network services. To check their operation, open the service management application:

In the context menu of the Windows (Start) button, click “Run”;

enter the command in the "Open" field of the "Run" application services.msc and click OK. The application will launch.

In the service management program, check the operation of the following components:

DHCP client;
DNS client;
Network Saving Interface Service;
Network configuration service.

If these Windows services are not running, the connection will not be created or will be limited to the local network only - no access to the Internet.

To configure autostart of network services along with Windows, open the properties of each of them (via the context menu).

Select Automatic from the Startup Type list. To start the service immediately, click the button of the same name in the “Status” section of the window.

Resetting Winsock and TCP/IP protocol settings

This operation restores the state of network structures - Windows 8 registry sections where the Winsock configuration is stored. To reset, use the Windows console utility - netshell.exe. Accordingly, it is launched via the command line (as an administrator).

To reset Winsock and the TCP/IP protocol, run two instructions in the console one after the other: netsh winsock reset And netsh int ip reset.

After this, restart your computer.

Fixing connection settings errors

To check the connection settings, go to the context menu of the Windows button (Start) and open the “Network Connections” folder.

Right-click to open the connection context menu and click “Status”.

The next window will display the main connection parameters:

DHCP protocol (assigns an IP address and other settings to a connection for working in TCP/IP networks) - whether enabled or not;
IPv4 address - if it starts with 169.254 (APIPA address range), then the connection is not receiving a valid IP from the DHCP server. This connection will always be limited and will not have access to the Internet.
Subnet mask - assigned automatically depending on the IP group.
The default gateway is the IP of the network device used as the gateway for this connection.
DNS server - the address of the server that maps domain names to host IP addresses.

To go to the settings, click the “Properties” button in the “Status” window. In the next window, check “IP version 4” in the list of components and click “Properties” again.

If the connection does not receive IP and other settings automatically, enter them manually. If your computer is connected to the Internet directly (without a gateway), check with your ISP for settings. When connecting through a gateway (router), one of the addresses in the local range to which the gateway belongs is assigned as an IP. For example, if the router address starts with 192.168.1, the connection address should start with the same numbers.

In the “Default gateway” field the IP of the router is indicated.

Information on disabling a third-party firewall can be found in its help.

Fixing other problems

There is no point in trying to reconfigure a connection on a corporate network that is limited by the administrator - it won’t work anyway. And if it is limited to the home, and this is definitely not the work of your loved ones, it is possible that a virus has entered the system. For the same reason, network access may be denied to individual applications. To solve the problem, scan your system with an antivirus and check your network settings again.

If the failure occurs in only one application, check the network access settings in it and the restriction rules for it in the Windows Firewall. If the source of the problem is not found, reinstall the program.