I con not bring up System VMs

i'm using CentOS 6.2 and KVM as hypervisor. My cloudstack version is 4.0.1. I am able to mount storage at hypervisor. 2013-05-07 10:41:41,278 DEBUG [cloud.capacity.CapacityManagerImpl] (consoleproxy-1:null) release cpu from host: 3, old used: 1000,reserved: 0, actual total: 2393, total with ov

Cloud -agent is dead, but the subsys is locked

Hello everyone: I am having an issue to add a kvm host. When I add the first kvm host ,I get a problem that "Unable to add the host" the service status : Cloud -agent is dead, but the subsys is locked