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How can I query the MAC address of the Nic? For this reason, this article specifically summarizes several query methods to help you easily "Eliminate all" the MAC addresses of various types of NICs "!

It is common that IP addresses are illegally stolen by others in the LAN. In this case, computers with stolen IP addresses cannot access LAN resources normally, on the computer screen, a prompt appears indicating that the IP address conflicts with the IP address of other devices. The Prompt window seriously affects daily computer operations. In order to avoid illegal IP address theft, many people choose to bind the MAC address and IP address of the NIC together to prevent others from illegally stealing the IP address, because the MAC address is actually the hardware address of the network card, the hardware address of each network card must be unique among all LAN devices. The address is uniformly allocated by the IEEE, in addition, it is "fixed" in the NIC, and common users cannot modify it at will. Before binding the MAC address and IP address of the NIC, you must obtain the MAC address of the NIC. How can you query the MAC address of the Nic? For this reason, this article specifically summarizes several query methods to help you easily "Eliminate all" the MAC addresses of various types of NICs "!

Recognize MAC addresses

Before querying a MAC address, you must first get to know it. Otherwise, it appears in front of you. You don't even know that it is the MAC address of the NIC, which is a joke. The MAC address is both the physical address of the nic and the link address of the NIC. It is written into the BIOS chip of the NIC when the NIC manufacturer manufactures the NIC. This address does not change with the network environment. Simply put, no matter which type of network you connect the network card with this hardware address to, the MAC address of the network card is the same. The MAC address length consists of 12-bit hexadecimal numbers. Each two hexadecimal numbers is separated by "-", for example, "00-30-6E-36-5A-EF ", the first six hexadecimal numbers of this address are uniformly allocated by IEEE, which indicates the specific ID of the NIC manufacturer, the last 6 bits in hexadecimal notation indicates the serial number of the NIC product produced by the manufacturer.

Command Query Method

After recognizing the MAC address, let's take a look at the command query method, which is the easiest way to query the MAC address of the Local Computer Nic. In this way, you can directly query the MAC address of the local Nic through the built-in network commands of the Windows system.

When using this method to query, you can click the "run" command in the "Start" menu of the system. In the displayed dialog box, run the "cmd" command to switch the screen to the doscommand line status; then, enter the "Ipconfig/all" string command at the doscommand prompt and click the Enter key. You will see the MAC address of the local Nic In the result screen shown in Figure 1. Of course, this command query method is only applicable to systems such as Win2000, WinXP, and Win2003.

Figure 1

If you are using Win98, WinMe and other operating systems, you can directly execute the "winipcfg" command in the MS-DOS state, in the subsequent IP configuration information interface, select the corresponding adapter option in the "Ethernet Adapter information" area, and then you can see the nic mac address in the "adapter address" area.

　　Comments:

Advantages: This method is easy to use and easy to operate, and can be quickly queried without the help of other tools;

Disadvantage: This method can only query the NIC address of a local computer, but cannot perform remote or batch query.

Protocol Query Method

This method queries information in the ARP protocol list in the local LAN through the Address Resolution Protocol-ARP command in the Windows system to obtain the MAC address of the NIC of other computers in the same network segment. The ARP protocol list contains the IP address and the resolved Token Ring or Ethernet physical address. However, once the TCP/IP protocol of the corresponding workstation is stopped and then restarted, the relationship between the IP address and the MAC address of the workstation disappears from the ARP protocol list. Therefore, if you want to view the MAC address of a workstation NIC that you have not accessed, you must use the ping command to access the IP address of the workstation. Then, the MAC address of the NIC corresponding to the IP address is automatically saved to the ARP protocol list, in this way, you can obtain the MAC address of the specified workstation through ARP command query.

When querying the MAC address of the NIC of another workstation, run the "Start"/"run" command in sequence, and Ping aaa in the "run" dialog box that appears later. aaa. aaa. aaa command (aaa. aaa. aaa. aaa is the IP address of the target workstation in the same CIDR Block), for example, after running the ping 61.155.52.201 command, if the workstation can be connected, you can switch the screen to the MS-DOS status, then run the "ARP-A" command. On the result page displayed in Figure 2, you can view the MAC address of the NIC corresponding to "61.155.52.201. On this page, you can also see the MAC addresses of other workstations that have been accessed.

Figure 2

　　Comments:

Advantage: This method is also easy to operate. You can remotely view it without going to another workstation;

Disadvantage: This method requires you to know the IP address of the target workstation in advance to query the MAC address.

Batch query

Because of the above method, you can only check the MAC address of the NIC of the workstation one by one. If the LAN contains many workstation, the above method obviously cannot meet the requirements of efficient network management. To this end, you can use some LAN management tools to quickly and batch query the MAC addresses of all workstations in a network segment. Here, we recommend a tool named "Exview", which allows you to conveniently query the MAC address of a local or remote workstation, you can also query the MAC addresses of all workstations in the specified LAN at one time.

When you use the "Exview" tool to query the MAC address of a LAN workstation, you must first download and install the "Exview" program in a workstation, then, click the start, program, Searchlight, and Exview commands. In the displayed main query interface, click the "options"/"configuration" command in the toolbar, and click the "m Modules" tab in the Figure 4 settings window that appears next, in the "optional modules" list on the corresponding tab, select the "NetBIOS" option and click ">" in the settings window, click OK to return to the main query interface;

Figure 4

Next, enter the starting IP address of a CIDR Block in "IP address slave" on the main query interface, enter the ending IP address of the CIDR Block in the "to" settings box, and click the "option" drop-down button, select "m Scan" from the pop-up drop-down list. To speed up the batch query of MAC addresses, you also need to enter a short time in the "delay" setting box, generally, the value is 100 milliseconds, and the number of "Threads" is set to be larger;

After completing the preceding settings, click the "operation"/"start" menu command on the main query interface in sequence. The "Exview" tool automatically scans each workstation in the specified network segment, in addition, all the NetBIOS information obtained by the scan is displayed. You can select the IP address of the workstation on the left side of the main query interface. The MAC address of the workstation is displayed in the corresponding subwindow on the right, 5.

Figure 5

　　Comments:

Advantage: This method is very suitable for users who are not familiar with system commands, and the address query efficiency of this method is very high.

Disadvantage: This method requires you to be familiar with the use of the "Exview" tool.