Conference kernel::csguk_systems

123.0. "5500 topics." by KERNEL::MOUNTFORD () Thu Dec 13 1990 18:46

From:	COMICS::BEDDALL "Peter Beddall - Product and Technology Group  13-Dec-1990 1520" 13-DEC-1990 15:32:58.80
To:	@QBUS,@ULTRIX
CC:	BEDDALL
Subj:	DS5500, Prestoserve and Documentation


    
    +-------------+
    | | | | | | | |                                                  
    |d|i|g|i|t|a|l|                         Product and Technology Group
    | | | | | | | |                                      
    +-------------+	      
    	                                    Interoffice Memorandum      
    
    
    To: Ultrixers                           Date:          13-DEC-1990
        QBUS TRF distribution               From:          Peter Beddall    
                                            Ext:           833 3804
    cc:	                                    Loc/mail stop: UVO Basingstoke
    	                                    DECnet:        COMICS::BEDDALL 
                                                           DECUK::pb

    Subject: DECsystem 5500, Prestoserve and Documentation.


    The DECsystem 5500 should begin FCS during the week  beginning  17th 
    December.  This  is  the  follow  on  product  to the DS5400 and has 
    improved performance capabilities over the DS5400, running  at  28.2 
    integer MIPS.

    Although  the  DS5500  utilises many similar maintenance features to 
    the  DS5400,  notably  a  CVAX  processor  for   running   MDM,   it 
    incorporates  a  new feature, Prestoserve. Prestoserve is a software 
    facility for disk acceleration that uses non-volatile storage on the 
    CPU  board  to  cache  data  writes  to  disk.  During normal system 
    shutdowns the cache is flushed to the disk, and the integrity of the 
    file  system  is  maintained.  If  however  the  system  is shutdown 
    abnormally either due to a hardware, software or power failure  then 
    the  cache  will contain data that should have been written to disk; 
    the cache is said to be dirty. Provided the system can be  rebooted, 
    any   such   data  is  recovered  automatically  during  the  reboot 
    sequence. 

    In the event that a reboot is not possible then it will be necessary 
    to save the contents of the cache, and restore them at a later time. 
    The contents of the cache can be manipulated and stored to a tape by 
    means of the maintenance mode command  "dc".  Procedures  for  doing 
    this  are  fully  described  in  Appendix  D of the KN220 CPU System 
    Maintenance  Guide  and  the  Ultrix  Guide  to  Prestoserve.  These 
    procedures  MUST  be followed before any maintenance is performed on 
    the system to avoid any possible corruption of the customers data.

    CPU modules contain a battery to maintain the contents of the NVRAM, 
    the battery is enabled by means of a jumper on the module.  All  new 
    modules  should be shipped from logistics with the battery disabled, 
    so engineers must ensure the battery is  enabled.  The  system  will 
    fail self test if the battery is disabled. 

    The   DS5500   documentation   can  be  obtained  electronically  in 
    postscript form from:
                                          
     COMICS::disk$users1:[beddall.5500].
    
    The files available are:


    Directory DISK$USERS1:[BEDDALL.5500]      
                                              
    EK-331AA-IN-001.PS;1       		! DECsystem 5500 Installation
                           7418               
    EK-332AA-OP-001.PS;1                ! DECsystem 5500 Operation      
                           4687               
    EK-348AA-MG-002.PS;1                ! BA440 Enclosure Maintenance
                           8076               
    EK-375AA-SM-001.PS;1                ! KN220 CPU System Maintenance      
                           2720               
    PRESTO_GUIDE.PS;1      1422         ! Ultrix Guide to Prestoserve      
                                              
    Total of 6 files, 24340 blocks.           
                                                                     

    Would  people  please only copy this documentation outside of normal 
    working hours.

    I hope to be able to distribute a list of  Customers  and  locations 
    destined for FCS at the earliest opportunity. 

    If  anyone  has  any  questions  regarding  the  DS5500  then do not 
    hesitate to call me. I  would  also  welcome  any  feedback  on  any 
    problems encountered on the initial DS5500 installations.


    Regards

    Pete Beddall