Hi!
the “TooManyDevices: Number of virtual devices exceeds the maximum for a given controller.” is being thrown by vCenter when OpenNebula is asking vCenter to perform a ReconfigVM task and set devices before the VM is powered on.
AFAIK OpenNebula does not set specific limits as it’s vSphere which already has limits per VM or ESX Hosts (vSphere maximums for version 6). For example vSphere limits the number of Virtual SCSI targets per virtual SCSI adapter to 15, 4 IDE devices per virtual machine, 10 vNICs per VM…
So I’d start trying to identify which kind of device is exceeding a vSphere limit for a VM, the Task Console in vCenter may give you more info as well as the VM hardware settings. Once you find the kind of device, compare the number of devices with what you have set in your VM in OpenNebula… if they don’t match and you find hardware devices that are duplicated or not supposed to be there, then maybe it’s a bug in OpenNebula (e.g BUG in vCenter with NIC [SOLVED]).
Cheers!