It looks like the problem is related to the fact that euca_conf --deregister will de-register a node, but the uec_component_listener is not informed when de-registration happens. Thus, if the component listener is restarted, it will re-register the node as soon as it sees the avahi publication of the node.
One possible avenue here would be to modify euca_conf in the UEC to send a signal of some sort (perhaps, by putting a message into registration.log, which uec_component_listener reads periodically?), to inform the listener that a node has been de-registered and should not be re-registered.
It looks like the problem is related to the fact that euca_conf --deregister will de-register a node, but the uec_component_ listener is not informed when de-registration happens. Thus, if the component listener is restarted, it will re-register the node as soon as it sees the avahi publication of the node.
One possible avenue here would be to modify euca_conf in the UEC to send a signal of some sort (perhaps, by putting a message into registration.log, which uec_component_ listener reads periodically?), to inform the listener that a node has been de-registered and should not be re-registered.