Load Balancer Packet Generation for Cross-VLAN Deployment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional DR mode for load balancing in large-scale cloud deployments across VLANs is not applicable due to the requirement for the load balancer and back-end host to be in the same VLAN, limiting scalability and availability in cross-VLAN cluster deployments.
Innovation Solution
A packet generation method and load balancer architecture that constructs an initial MAC address for a destination server, allowing data packets to be sent across VLANs without modifying the source IP address, enabling effective communication by updating the destination IP address based on the initial MAC address obtained through ARP requests, and utilizing a DR module to determine the destination server and send ARP request packets.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If conventional DR mode is used for load balancing, then the load balancer and back-end host can be in the same VLAN, but this limits scalability and availability in cross-VLAN cluster deployments
Solution Approach 1:
The patent introduces an intermediary mechanism (ARP request/response processing and MAC address translation) that enables communication between the load balancer and back-end hosts across different VLANs. The load balancer acts as a mediator that receives client requests, determines the destination server, obtains the server's MAC address through ARP, translates the destination IP address based on the MAC address, and forwards the packet to the appropriate VLAN, thereby resolving the VLAN isolation issue while maintaining system availability
Solution Approach 2:
The patent segments the network communication process into distinct stages: client request reception, destination server determination, MAC address acquisition via ARP, IP address translation, and packet forwarding to the appropriate VLAN. This segmentation allows each component to operate independently within its own VLAN while maintaining overall system connectivity and availability
2Adaptability or versatility
If the load balancer and back-end host are in the same VLAN, then communication is straightforward, but this restricts large-scale cloud deployment across multiple VLANs
Solution Approach 1:
The patent changes the network layer parameters (IP address translation based on MAC address) to enable cross-VLAN communication. By dynamically translating the destination IP address according to the obtained MAC address and the target VLAN, the system adapts to different network configurations without requiring complex manual routing setups, thus facilitating large-scale cloud deployment while managing complexity
3Ease of operation
If source IP address is modified in cross-VLAN transmission, then routing is simplified, but the original client IP address information is lost
Solution Approach 1:
The patent extracts and preserves the original source IP address from the client request packet and maintains it throughout the cross-VLAN transmission process. Only the destination IP address is translated based on the MAC address and target VLAN, while the source IP address remains unchanged, allowing the system to achieve simplified routing for the destination while preserving complete client identification information for auditing and analysis purposes
Data Source
AI summary
A packet generation method based on a server cluster and a load balancer, where the method includes receiving a client request packet, determining a destination server according to a preset load balancing policy, sending an Address Resolution Protocol (ARP) request packet according to the destination Internet Protocol (IP) address, obtaining an ARP response packet according to the ARP request packet, the initial Media Access Control (MAC) address is different from an actual MAC address of the destination server, and updating the destination IP address according to the initial MAC address to obtain an updated client request packet, where the updated client request packet includes the source IP address and an updated destination IP address. In this way, in a process of transmitting a packet, a source IP address of a client is detected on a network layer without changing a source IP address in a request packet.