H133777 - SERVER BACKPLANE ADDRESS JUMPER CONFIGURATION
 
 SYMPTOM:
 Servers with hot-swap backplanes may experience intermittent
 drive errors, defunct (DDD) drives that don't spin down or
 drive LEDs that don't blink when a drive has failed.
 
 PROBLEM ISOLATION AIDS:
 The system is an 8641, 8642 or 3518 with one or more hot swap
 backplanes installed.
 
 FIX:
 Check the Backplane Address Jumper:
 1. Shutdown the operating system
 2. Power off the server.
 3. Verify the Backplane Address Jumper configuration:
   a. For ALL 8641 backplanes: Jumpers should NOT be present
      on the pins for Bank0, Bank1, or Bank2 on any backplane.
      Refer to Figure 1.
      The PC Server 520 (8641) may have shipped with a backplane
      address jumper installed; it should be removed.
 
   b. For 8642 and 3518 backplanes: Each backplane MUST have a
      unique address. A jumper should be present on the pins
      for Bank0, Bank1, OR Bank2 depending on the backplane's
      location within the server or expansion enclosure.
      Refer to Figure 1 and Table 1 below to determine the
      correct jumper setting for an 8642 or 3518 backplane:
 
 For additional jumper information on the 3518 backplane,
 refer to RETAIN record H134356.
 
 Figure 1    BACKSIDE of BACKPLANE  (Not to Scale)
 .-------------------------- HI -------------------------------.
 |                   ___     o   No jumper should be     ___   |
 | Power            |   |    o   installed here.  If    |   |  |
 | Connector        |   |    o   present, it should     |   |  |
 |  ___             |   |    LO  be set to LO.          |   |  |
 | | o |            |   |                               |   |  |
 | | o |            | S |                               | S |  |
 | | o |            | C |                               | C |  |
 | | o |            | S |                               | S |  |
 | |___| .. Bank2(E)| I |                               | I |  |
 |       .. Bank1(D)|___|                               |___|  |
 |       .. Bank0(C)                                           |
 ---------------------------------------------------------------
 
 Table 1
 
 Jumper Position | Backplane Location
 ----------------|-------------------
     Bank0       |     Bank C
     Bank1       |     Bank D
     Bank2       |     Bank E
 
 Note:
 The documentation in the Server 520 User's Handbook, part number
 62H7096, page 177 is incorrect.  Backplane address jumpers
 should NOT be installed on any Server 520 backplanes.
 
 March 18, 1997