I would like input from the community. Would load balancing DHCP requests across multiple servers using Cisco switches provide true-load balancing where the load is evenly distributed based on server capacity or current load using 2 IP helper-addresses.
My understanding is that this method does not provide a true load-balancing mechanism where the load is evenly distributed based on server capacity or current load. Instead, it relies on the DHCP client's behavior of accepting the first offer it receives from the Microsoft servers. This can result in a form of load distribution, but it's more stochastic than deterministic.
How I see it, when configuring multiple IP helper addresses for the purpose of distributing load we need to remember :
DHCP Server Configuration: Ensure each DHCP server has a scope configured that does not overlap with the others, or if using a shared scope, that the servers coordinate to avoid IP address conflicts.
Client Behavior: DHCP clients will typically accept the first DHCP offer received. This behavior inherently creates a form of load distribution, as the fastest server to respond is likely to serve the request.
Network Latency: Network latency and server response times can influence which server responds first, affecting how requests are distributed.
This configuration does not guarantee an even load distribution across the DHCP servers but does increase the resilience and availability of DHCP services by allowing multiple servers to handle requests.
For environments requiring more precise load balancing of DHCP (or other services), we need to consider using dedicated load balancers that can distribute traffic based on server load, response time, or other criteria. Cisco Application Centric Infrastructure (ACI) and other SDN solutions offer more sophisticated load-balancing capabilities that can be applied to a variety of services, including DHCP.
Any input would be appreciated verifying my understanding.
