I inherited an existing Aerohive environment and was always annoyed by pervasive CAPWAP connection failed messages and even more by intermittent but persistent issues with configuration update delays and failures. Nothing I found in the knowledgebase was helping. One day I was repairing a network jack and I realized the infrastructure cabling that the WAPs are connected to is only CAT 5. We were running the WAP network ports at 1 Gbps. I set the switchports down to 100 Mbps and it was like night and day. All the CAPWAPs alerts went away and the updates are as smooth as silk so if you're having issues validate your cable plant. If you're in an old building it's likely populated with CAT5 and 100 Mbps will be your rated limit.