After having numerous questions regards maximum number of APs we could have in a cluster (Express mode here) I think it is interesting to make a point on the subject here.
As a reminder, rules within Stellar cluster in Express mode depend on AP models present in the cluster, specially for the maximum of APs the cluster can reach. They are the following in all releases 4.0:
- A cluster built with AP1101 and AP1201H access points only can have 32 APs maximum. - A cluster built with a minimum of 4 AP12XX access points (serie AP1220/AP1230/AP1251/AP1201) or a minimum of 4 AP13XX access points (serie AP1320/AP1360) can have 64 APs. - A cluster built with a minimum of 8 AP12XX access points (serie AP1220/AP1230/AP1251) or a minimum of 8 AP13XX access points (serie AP1320/AP1360) can have 255 APs within the cluster.
Regards Virtual Managers election rules in Express mode (Primary Manager & Secondary Manager) rules stay the same as previous Stellar releases; knowing any AP within the cluster is eligible to become primary manager (PVM); the highest MAC within a serie (AP13XX, AP12XX then AP1101/AP1201H) acts as PVM and the second highest MAC acts as secondary manager for rescue (SVM). All other APS in the cluster are members and are called members. The PVM centralizes the cluster management and cluster is identified by ID. Any AP which want to connect to the cluster and exceeds limit of members defined above is rejected.
More recommandations are detailed in last Stellar user guide.