This is the first day of my participation in Gwen Challenge
Fault: The network configuration of server A and server B is as follows. The subnet mask of server B should be255.255.255.0“Was accidentally matched255.255.255.224Are they still normal?
PC2 pings PC1 and finds that PC1 can communicate
The following describes the packet capture process using Wireshark
1. PC2 throughARP broadcastQuerying the Default Gateway192.168.0.1The MAC address of. Why do I ping server A’s IP address while SERVER B queries the MAC address of the default gateway? This is because PC2, based on its subnet mask,Calculate that A belongs to different subnets.Cross-subnet communication requires forwarding by the default gateway. To communicate with the default gateway, you need to obtain its MAC address.
2.PC2 sends a ping packet and specifies Destination IP as PC1192.168.0.129. However, Destination MAC is the default gateway. This indicates that PC2 wants the default gateway to forward the packet to PC1.
3.PC1 also receives the ARP request packet from the gateway and responds
4. As can be seen from the following packages, this communication process is proxyed by the gateway
In theory, PC2 sends the ping request to the default gateway, which forwards it to PC1. PC1 directly responds to the ping request to PC2, forming a triangular loop as shown in the following figure. But the actual communication process is made up ofThe gateway performs proxy communication
Now look at the communication between PC1 and PC2
Packet capture on port PC1
Observing an ICMP packet shows that the traffic is also brokered by the gateway
Take a look at the packets on the PC2 port, and their communication is also done through the gateway
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