@klnnnnng wrote:
9800-40, 2000+ AP's and 10k client peak.
9800-40 cannot handle >1000 x APs.
Read the 03 May 2024 revision of the Cisco Catalyst 9800 Series Configuration Best Practices. Half of the document talks about the role of the WNC daemon (aka "load balancer"). (There are 4 WNCD queue in the 9800-40 and 8 WNCD in the 9800-80.) This document talks about the "80% rule":
C9800 design is no different and, generally, Cisco recommends limiting the load to around 80% of the AP and client scale.
The 80% scale is just a recommendation to start planning the design and deployment of a catalyst wireless network as this is tested and validated number.
For C9800-80, for example, this means 4800 APs and/or around 50k clients. Does this mean that you cannot have six thousand APs on a single C9800-80? No, not really; Cisco has a lot of successful deployments at maximum scale. The 80% scale is just a recommendation to start planning the design and deployment of a catalyst wireless network.
Poor quality of the firmware has caused the WNCD to spring memory leaks when certain conditions are exceeded. Among them are:
- >50% AP load;
- >50% peak client count;
- HA SSO
- Inter-controller roaming
- Web Authentication
Below is the control-plane memory utilization of our 9800-80 (firmware 17.12.3) with an uptime of 12 weeks:
Before the spike, our controller had 2900 APs. As soon as the AP count exceeded 3000 APs, the control-plane memory utilization increase due to memory leaks.
