A server system comprising at least two server nodes in an Infrastructure as a Service cloud (IaaS), each server node comprising a hypervisor and a plurality of virtual machines at least a subset of which depend on each other to provide a service and together defining at least one application distributed across said at least two server nodes utilizing said IaaS cloud, each server node further comprising: a cloud infrastructure monitor within the hypervisor, said cloud infrastructure monitor comprises: a monitor arrangement configured for monitoring an infrastructure of said IaaS cloud by monitoring at least one of a physical network, storage within said physical network, the server node, or at least one of said plurality of virtual machines, and a detector arrangement configured for detecting faults within said monitored IaaS infrastructure, and a notifying arrangement configured for providing notifications of detected faults on a message bus; the server system further comprising a respective message bus arranged between at least two hypervisors located in different server nodes and each said at least one application for relaying said fault notifications from said cloud infrastructure monitor to said at least one application; each said at least one application is configured to automatically manage its operation in response to received fault notifications, and wherein at least one server node is connectable to an application registry configured to store application identities for each said at least one application, and a bus registry configured to store a respective message bus for each said at least one application. a cloud infrastructure monitor within the hypervisor, said cloud infrastructure monitor comprises: a monitor arrangement configured for monitoring an infrastructure of said IaaS cloud by monitoring at least one of a physical network, storage within said physical network, the server node, or at least one of said plurality of virtual machines, and a detector arrangement configured for detecting faults within said monitored IaaS infrastructure, and a notifying arrangement configured for providing notifications of detected faults on a message bus; a monitor arrangement configured for monitoring an infrastructure of said IaaS cloud by monitoring at least one of a physical network, storage within said physical network, the server node, or at least one of said plurality of virtual machines, and a detector arrangement configured for detecting faults within said monitored IaaS infrastructure, and a notifying arrangement configured for providing notifications of detected faults on a message bus; a respective message bus arranged between at least two hypervisors located in different server nodes and each said at least one application for relaying said fault notifications from said cloud infrastructure monitor to said at least one application; each said at least one application is configured to automatically manage its operation in response to received fault notifications, and wherein at least one server node is connectable to an application registry configured to store application identities for each said at least one application, and a bus registry configured to store a respective message bus for each said at least one application.