4.1.2 Replacing a PDU

This procedure describes how to replace a power distribution unit (PDU).

1. Use the PDU monitor as follows to identify its network settings, if it is not the reason for the PDU replacement:
   1. Press the reset button for 20 seconds until it starts to count from 5 to 0. While it is counting down, release the button, and then press it once.
   2. Record the network settings, firmware version, and so on, displayed on the LCD screen as the monitor restarts.

      Note:

      If the PDU monitor is not working, then retrieve the network settings by connecting to the PDU over the network, or from the network administrator.
2. Turn off all the PDU breakers.
3. Unplug the PDU power plugs from the AC outlets.

   Note:

   • If the power cords use overhead routing, then put the power plugs in a location where they will not fall or hit anyone.
   • If the rack is on a raised floor, then move the power cords out through the floor cutout. It may be necessary to maneuver the rack over the cutout in order to move the power cords out.
4. Do the following procedure for a PDU-B replacement when there is not side panel access, and the rack does not have an InfiniBand cable harness:

   Note:

   Do not unstrap any cables attached to the cable arms.
   1. Unscrew the T25 screws holding the square cable arms to the rack.
   2. Move the RDMA Network Fabric cables to the middle, out of the way.
5. Unplug all power cables going from the servers and switches to the PDU. Keep the power cables together in group bundles.
6. Remove the T30 screws from the top and bottom of the L-bracket, and note where the screws go.
7. Note where the PDU sits in the rack frame. It is usually 1 inch back from the rack frame to allow access to the breaker switches.
8. Angle and maneuver the PDU out of the rack.
9. Hold the PDU or lay it down, if there is enough room, while maneuvering the AC power cords through the rack. It may be necessary to cut the cable ties that hold the AC cord flush with the bottom side of the PDU.
10. Pull the cords as near to the bottom or top of the rack as possible where there is more room between the servers to get the outlet plug through the routing hole.
11. Remove the smaller Torx T25 screws, and loosen the nut on the top and bottom to remove the PDU from the L-bracket. The nut does not have to be removed.
12. Attach the L-bracket to the new PDU.
13. Lay the new PDU next to the rack.
14. Route the AC cords through the rack, and to where the outlets are.

    Note:

    Do not cable tie the AC cord to the new PDU at this time.
15. Place the new PDU in the rack by angling and maneuvering it until the L-brackets sit on the top and bottom rails.
16. Line up the holes and slots so that the PDU sits about 1 inch back from the rack frame.
17. Attach the power cords using the labels on the cords as a guide.
    For example, G5-0 indicates PDU group 5 outlet 0 on the PDU.
18. Attach the InfiniBand cable holders if they were removed in step 4.

    Oracle recommends screwing the holders in by hand at first to avoid stripping the screws.

19. Attach the AC power cords to the outlets.
20. Turn on the breakers.
21. Cable and program the PDU monitor for the network, as needed.