Patent Publication Number: US-2013246816-A1

Title: Power distribution unit and method using a single internet protocol address to control multiple power distribution units

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a power distribution unit (PDU) and a method using a single internet protocol (IP) address to control multiple power distribution units, and more particularly to a power distribution unit and a method virtualizing outlets of at least one networked PDU as outlets of another networked PDU and using one IP address to control all the outlets of each networked PDU. 
     2. Description of the Related Art 
     PDUs have been extensively used for power management of information technology (IT) equipment for years. To cope with the demand of supplying power to a multitude of IT equipment or peripheral equipment, multiple rackmount PDUs are mounted on racks for mounting IT equipment to respectively provide multiple outlets for multiple IT equipment, such as servers, routers, firewalls and the like, or peripheral equipment, such as printers, displays, fax machines and the like, to be connected therewith, so as to supply power to the IT equipment or peripheral equipment. Each rackmount PDU is further connected to a corresponding uninterruptible power supply (UPS) system to simultaneously support the function of UPS. Conventional rackmount PDUs can be classified into basic rack PDUs, metered rack PDUs, switched rack PDUs and intelligent rack PDUs. Among them, the metered rack PDUs and the intelligent rack PDUs can be remotely powered on or off through a network. 
     Conventional PDUs may be 1 U or 2 U in height, and each conventional PDU roughly has 8 to 16 outlets, which is usually outnumbered by equipment on the racks. Hence, more PDUs are required as current technique supports up to 16 PDUs at most. As mentioned earlier, PDUs are characterized in remote control through a network. In other words, a control center connected to multiple PDUs needs to log in each PDU and further control each outlet on the PDU to power on or off equipment connected to the outlet. However, each PDU must have a dedicated IP address. If 16 PDUs are serially connected, 16 IP addresses are needed. To monitor or control each PDU, a correct IP address must be used to log in to a corresponding PDU. Memorizing 16 or more IP addresses turns out to be a challenging job to all managers. 
     To facilitate the control over PDU, PDUs are connected in a daisy chain configuration so that a physical line, normally RJ11/RJ45, is connected between PDUs. The connected PDUs are defined to have a master PDU and multiple slave PDUs, and the master PDU communicates with the slave PDUs through the daisy-chained physical lines. Thus, users just need to log in the master PDU and information of all the PDUs can be accessible so that one IP address is employed to manage all the connected PDUs. 
     As physical lines must be used to daisy chain all the PDUs, such requirement increases wiring difficulty in racks having complicated wiring. Distance limitation further worsens the feasibility of using physical lines to implement a daisy chain loop. Under the circumstance, all daisy-chained PDUs are connected as adjacent as possible, thereby lowering the flexibility in terms of mounting position of PDU. If space next to a PDU in a rack is occupied by other IT equipment, the equipment must be demounted and mounted to elsewhere to make space for a new PDU to be mounted. Moreover, the daisy-chained physical lines are at risk of being disconnected while there is no easy way for managers to identify where the disconnected line is located. 
     Besides the daisy chain connection, another solution is to set up a server and connect to PDUs through central control software in the server. The advantage lies in a single IP address used to centrally control all connected PDUs. The disadvantage lies in costly software packages required for network management, such as HP OpenView/IBM Tivoli and the like, which are not affordable to small to medium sized enterprises. Except an IT environment, other environments, such as production lines of factories, pond aeration systems, irrigation systems and lighting system for small sized agriculture, are not appropriate for setting up a server. Limited by the factors of cost and environment, the technique using software in a server to centrally control the connected PDUs has never prevailed. 
     SUMMARY OF THE INVENTION 
     A first objective of the present invention is to provide a method using a single IP address to control multiple PDUs, which targets at virtualizing the outlets of at least one PDU as the added outlets of a login PDU so as to centrally control the outlets of multiple PDUs without costing a lot and being limited by the length limitation of physical line. 
     To achieve the foregoing objective, the method uses a single IP address to control multiple PDUs respectively having multiple outlets and connected to a network, is performed by one of the PDUs operated at a login mode and has steps of: 
     accepting to be logged in as a login PDU; 
     providing an html-based user interface to accept at least one PDU that is not logged in as at least one non-login PDU and virtualizing the outlets of the at least one non-login PDU as added outlets to the original outlets of the login PDU; 
     handshaking with each one of the at least one non-login PDU; 
     receiving outlet information from the at least one non-login PDU; 
     displaying the outlets of the login PDU and the at least one non-login PDU; and 
     accepting to control the displayed outlets. 
     The method allows users to select one of the PDUs connected to a network to be logged in with an IP address. The html-based user interface is used to display the outlets of the login PDU and virtualize the outlets of other PDUs not logged in as the added outlets to the original outlets of the login PDU. After handshaking with the virtualized PDUs, outlet information of the virtualized PDUs is transmitted to the login PDU and displayed on the user interface for user to issue a control command through the network to control one of the added outlets of the login PDU. Accordingly, the method uses a single IP address to centrally control the outlets of all the networked PDUs. 
     A second objective of the present invention is to provide a PDU, which targets at virtualizing the outlets of at least one PDU as the added outlets of a login PDU so as to centrally control the outlets of multiple PDUs through a user interface without costing a lot and being limited by the length limitation of physical line. 
     To achieve the foregoing objective, the power distribution unit (PDU) is selected from multiple PDUs connected to a network and performs the foregoing method using a single IP address to control the PDUs. 
     The PDU has multiple outlets, at least one network port and a controller. The outlets are adapted to be detachably connected with a power source. The controller is connected to each outlet and the at least one network port, is adapted to control the outlet to be detachably connected with the power source, and provides the html-based user interface having a virtual outlet setting page and an outlet display and control page. 
     The virtual outlet setting page is used to add other PDUs and virtualize the outlets of those PDUs as added outlets to the original outlets. 
     The outlet display and control page is used to display and control the outlets of all the PDUs. 
     The advantages of the present invention are as follows. 
     (1) Control multiple PDUs with one IP address: The present invention virtualizes the outlets of at least one PDU as the added outlets to the original outlets of a login PDU so that the login PDU can access the outlet information of all the PDUs. Hence, users just need to log in one of the PDUs with one IP address to centrally control the outlets of all the PDUs on a user interface of the login PDU. 
     (2) No length limitation of physical line: All the PDUs of the present invention are connected through network lines instead of daisy-chained physical lines. It is not necessary for all the PDUs to be adjacent to each other, thereby rending more flexibility in terms of the mounting and connection of the PDUs. 
     (3) No requirement on dedicated computer server and expensive central management software: All PDUs of the present invention can be operated under a regular protocol, and no dedicated computer server and central management software are required. Accordingly, operational cost can be effectively reduced. 
     Other objectives, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic view of a power distribution unit in accordance with the present invention; 
         FIG. 2  is a schematic view of a user interface of the power distribution unit in  FIG. 1 ; 
         FIG. 3  is a schematic view of another user interface of the power distribution unit in  FIG. 1 ; 
         FIG. 4  is a schematic view of a network architecture of the power distribution unit in  FIG. 1 ; 
         FIG. 5  is a flow diagram of a login operation mode of a method using a single IP address to control multiple PDUs in accordance with the present invention; and 
         FIG. 6  is a flow diagram of a non-login operation mode of a method using a single IP address to control multiple PDUs in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     With reference to  FIG. 1 , a power distribution unit (PDU)  10  in accordance with the present invention has multiple outlets  11 , at least one network port  12  and a controller  13 . The outlets  11  and the at least one network port  12  are mounted on the PDU. Each outlet  11  has a power loop detachably connected with a power source. The controller  13  is connected to each outlet  11  and controls the power loop of the outlet  11  to power on or off. The network port  12  is connected to the controller  13  and an external network, and is based on a wireline protocol, such as Ethernet or the like, or a wireless protocol, such as WLAN, WIFI, ZIGBEE or the like. 
     The controller  13  has an html-based user interface for at least one computer to connect to and browse through a network complying with the wireline or wireless protocol. The user interface has a virtual outlet setting page  100  and an outlet display and control page  200  for performing a virtual outlet setting function. 
     With reference to  FIGS. 2 and 4 , the virtual outlet setting page  100  has a login IP display column  101 , a new equipment identification input column  102 , an equipment name input column  103  and a current equipment display column  104 . 
     The login IP display column  101  serves to display the IP address of the PDU  10  itself. When users log in with the IP address of the PDU  10  and enter the virtual outlet setting page  100 , the IP address is displayed in the login IP display column  101 . 
     The new equipment identification input column  102  further has an “add” button  102 A. The new equipment identification input column  102  and the equipment name input column  103  serve for users to add another one of the PDUs  10 ′ and virtualize multiple outlets  11  of the added PDU  10 ′ as added outlets to the original outlets  11  of the PDU  10 . The newly added PDU  10 ′ is structurally the same as the PDU  10  except that it is not logged in. The way of virtualizing the outlets  11  of the newly added PDU  10 ′ as added outlets to the original outlets  11  of the PDU  10  is to first enter identification information of the newly added PDU  10 ′ in the new equipment identification input column  102 , further enter a name of the newly added PDU  10 ′ in the equipment name input column  103 , and press the “add” button  102 A to confirm the new addition. The identification information may be an IP address, a media access control (MAC) address or a serial number. In the present embodiment, the identification information is an IP address, that is, “10.10.27.131”, of a newly added PDU inputted in the new equipment identification input column  102 . The PDU  10  further handshakes with the newly added PDU  10 ′ through the network and receives outlet information returned from the newly added PDU  10 ′ to virtualize the outlets  11  of the newly added PDU  10 ′ as added outlets to the original outlets  11  of the PDU  10  and add the newly added PDU  10 ′ to the current equipment display column  104  after the handshaking is completed. As all the newly added PDUs  10 ′ have identifiable MAC addresses and serial numbers, after connected to the network, the PDU  10  automatically searches all the newly added PDUs  10 ′ having the outlets  11  virtualized as added outlets to the original outlets  11  of the PDU  10  and displays a search result in the new equipment identification input column  102 . The new equipment identification input column  102  is a drop-down list for users to directly click and select from. 
     With reference to  FIG. 3 , the outlet display and control page  200  of the aforementioned user interface has a login IP display column  201 , a control command selection column  202 , an original outlet list  203  and at least one virtual outlet list  204 . 
     The login IP display column  201  also displays the login IP address of the PDU  10 . The control command selection column  202  serves for users to select an outlet control command, such as turn on, turn off, restart or the like, to be performed. The original outlet list  203  lists information pertinent to each outlet  11  of the PDU  10 , such as an operation status (ON/OFF/RESTART), an outlet number (1˜8) and a name of equipment connected to the outlet  11  (servers A˜D and computers A˜D). Furthermore, the original outlet list  203  has a checkbox  203 A for each outlet  11 . When intending to vary the power state of the outlet  11 , users can click on the checkbox  203 A of the outlet  11  and then change the outlet control command in the control command selection column  202 , and the newly selected outlet control command is sent to the controller for the controller to configure a new operation status, for example, changing from turn on to turn off or changing from turn off to restart. 
     Each one of the at least one virtual outlet list  204  is approximately the same as the original outlet list  203  except that different PDUs are displayed and controlled, and serves to display the outlet information of the newly added PDUs  10 ′. The outlets  11  of the newly added PDUs  10 ′ having the displayed outlet information have been virtualized as the outlets of the PDU  10 . Although the outlets  11  of the newly added PDUs  10 ′ are virtualized as the outlets of the PDU  10 , when handshaking with the PDU  10 , the newly added PDUs  10 ′ transmit the outlet information to the PDU  10 . Hence, the PDU  10  can display the outlet information of the newly added PDUs  10 ′ on the at least one virtual outlet list  204  of the outlet display and control page  200  associated with the PDU  10 . The at least one virtual outlet list  204  lists the outlet information of the newly added PDUs  10 ′, including the operation statuses (ON/OFF/RESTART), the outlet numbers (1˜8) and the names of equipment connected to the outlet (printers A˜D and monitors A˜D). Furthermore, the virtual outlet list  204  has a checkbox  204 A for each outlet. When intending to vary the power state of the outlet, users can click on the checkbox  204 A of the outlet and then change the outlet control command in the control command selection column  202 , and the newly selected outlet control command is sent to the controller for the controller to configure a new operation status. 
     With reference to  FIG. 4 , a network architecture of the power distribution unit in accordance with the present invention has multiple PDUs  10 ,  10 ′ connected to a network. The controller of each PDU  10 ,  10 ′ has a procedure stored therein and operated in a login mode or a non-login mode. The login mode is activated when a corresponding PDU  10 ,  10 ′ is logged in with an IP address. The non-login mode is activated when a corresponding PDU  10 ,  10 ′ is not logged in with an IP address. Suppose that the PDU  10  is the one logged in with an IP address, but the rest of PDUs  10 ′ are not logged in with an IP address. Therefore, the PDU  10  is operated under the login mode, and the rest of PDUs  10 ′ are operated under the non-login mode. Among all the PDUs  10 ,  10 ′, there is only one PDU  10  that is logged in with an IP address and operated under the login mode. 
     With reference to  FIG. 5 , after multiple PDUs  10 ,  10 ′ respectively having multiple outlets  11  are connected to a network, a method using a single IP address to control multiple outlets  11  in accordance with the present invention is performed by one of the PDUs  10  at a login mode and has the following steps. 
     Step  501 : Accept to be logged in as a login PDU  10 . 
     Step  502 : Provide an html-based user interface to add at least one PDU  10 ′ that is not logged in as at least one non-login PDU  10 ′ and virtualize the outlets  11  of the at least one non-login PDU  10 ′ as added outlets to the original outlets  11  of the login PDU  10 . 
     Step  503 : Handshake with each one of the at least one non-login PDU  10 ′. 
     Step  504 : Receive outlet information from the at least one non-login PDU′  10 ′. 
     Step  505 : Display the outlet information of all the PDUs  10 ,  10 ′. 
     Step  506 : Determine if an outlet control command associated with one of the original outlets  11  and added outlets of the PDU  10  is received. 
     Step  507 : Further determine if the outlet control command is associated with one of the original outlets  11  or the added outlets of the login PDU  10  after the outlet control command is inputted. 
     Step  508 : If the outlet control command is associated with one of the added outlets of the login PDU  10 , transmit the outlet control command to a corresponding non-login PDU  10 ′ actually having the added outlet through the network to instruct the non-login PDU  10 ′ to execute the outlet control command. 
     Step  509 : If the outlet control command is associated with one of the original outlets  11  of the login PDU  10 , execute the outlet control command associated with the original outlet  11 . 
     With reference to  FIG. 6 , after multiple PDUs  10 ,  10 ′ respectively having multiple outlets  11  are connected to a network, the method is performed by one of the PDUs  10 ′ at a non-login mode and has the following steps. 
     Step  601 : Handshake with the login PDU  10 . 
     Step  602 : Set itself as a non-login PDU  10 ′. 
     Step  603 : Transmit outlet information to the login PDU  10 . 
     Step  604 : Determine if an outlet control command associated with one of its own outlets  11  is received from the login PDU  10 . 
     Step  605 : If positive, execute the outlet control command, and if negative, return to Step  604 . 
     The technical solution of the present invention targets at using one IP address to log in one of multiple PDUs  10  connected with a network and virtualizing the outlets  11  of other PDUs  10 ′ as added outlets to the original outlets  11  of the login PDU  10 . Accordingly, users just need to log in one PDU  10  and all the outlets can be centrally monitored and controlled through a common user interface of the login PDU  10 . 
     As any one of multiple networked PDUs can be selected as a login PDU  10  and the outlets  11  of the rest of PDUs  10 ′ can be virtualized as the added outlets to the original outlets  11  of the login PDU  10 , a master-slave network platform is not a must. Since all PDUs  10 ,  10 ′ are connected and operated through network lines, no other physical lines are required. Accordingly, the PDU and method of the present invention provide more convenience and flexibility to users in terms of operation and maintenance and save the cost for purchasing network management software. 
     Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only. Changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.