We used a user with read-only role assigned in a vSphere 5.1 vCenter to monitor the vSphere environment (with Check_MK / Nagjos) and to backup the VMs (with Quantum). Since we installed vSphere 5.5 vCenter and VMware ESXi 5.5, the same user identically defined, can't monitor or backup the environment anymore. We needed to give him full permission.
Was could be the problem? Thanks a lot for any help!