A rack system, comprising at least a first server system and a second server system, the first server system comprising: one or more first cooling components; a first controller configured to control the one or more first cooling components; a first cooling control switch, configured to switch the one or more first cooling components between the first controller and a second controller of the second server system; a first watch dog circuit; the second server system comprising: one or more second cooling components; the second controller configured to control the one or more second cooling components; a second cooling control switch, configured to switch the one or more second cooling components between the second controller and the first controller of the first server system; and a second watch dog circuit; the first watch dog circuit is configured to: determine health of the first controller; and in an event that the first controller has failed, enable the first cooling control switch to an external mode to connect the one or more first cooling components to the second controller of the second server system thereby allowing the second controller of the second server system to control the one or more first cooling components; the second watch dog circuit is configured to: determine health of the second controller; and in an event that the second controller has failed, enable the second cooling control switch to the external mode to connect the one or more second cooling components to the first controller of the first server system thereby allowing the first controller of the first server system to control the one or more second cooling components. one or more first cooling components; a first controller configured to control the one or more first cooling components; a first cooling control switch, configured to switch the one or more first cooling components between the first controller and a second controller of the second server system; a first watch dog circuit; the second server system comprising: one or more second cooling components; the second controller configured to control the one or more second cooling components; a second cooling control switch, configured to switch the one or more second cooling components between the second controller and the first controller of the first server system; and a second watch dog circuit; the first watch dog circuit is configured to: determine health of the first controller; and in an event that the first controller has failed, enable the first cooling control switch to an external mode to connect the one or more first cooling components to the second controller of the second server system thereby allowing the second controller of the second server system to control the one or more first cooling components; the second watch dog circuit is configured to: determine health of the second controller; and in an event that the second controller has failed, enable the second cooling control switch to the external mode to connect the one or more second cooling components to the first controller of the first server system thereby allowing the first controller of the first server system to control the one or more second cooling components. one or more second cooling components; the second controller configured to control the one or more second cooling components; a second cooling control switch, configured to switch the one or more second cooling components between the second controller and the first controller of the first server system; and a second watch dog circuit; the first watch dog circuit is configured to: determine health of the first controller; and in an event that the first controller has failed, enable the first cooling control switch to an external mode to connect the one or more first cooling components to the second controller of the second server system thereby allowing the second controller of the second server system to control the one or more first cooling components; determine health of the first controller; and in an event that the first controller has failed, enable the first cooling control switch to an external mode to connect the one or more first cooling components to the second controller of the second server system thereby allowing the second controller of the second server system to control the one or more first cooling components; the second watch dog circuit is configured to: determine health of the second controller; and in an event that the second controller has failed, enable the second cooling control switch to the external mode to connect the one or more second cooling components to the first controller of the first server system thereby allowing the first controller of the first server system to control the one or more second cooling components. determine health of the second controller; and in an event that the second controller has failed, enable the second cooling control switch to the external mode to connect the one or more second cooling components to the first controller of the first server system thereby allowing the first controller of the first server system to control the one or more second cooling components.