Mirroring Ringnodes Using MMIRROR.NLM
===================================== 
                                               LSS 5.0(0), August 1996 
                                               -----------------------
Summary
-------

Ringnode mirroring is  a  way  of  protecting  network  users  against 
hardware  failures  such  as  cable  faults. 

This file has the following sections: 
  1) Server Adapter mirroring overview
  2) Drivers supported
  3) Using MMIRROR.NLM
  4) Command line parameters


1) Server Adapter mirroring overview
------------------------------------
To perform server adapter mirroring you need to install a second Madge 
Smart  Ringnode  which  can  take  over from the first. If the primary 
Ringnode fails, the  standby  Ringnode  takes  over  from  it  without 
affecting  the  higher  level  protocols  of  either the server or any 
workstations.


2) Drivers Supported
--------------------
The Madge Mirrored Ringnode feature is implemented by  an  NLM  called 
MMIRROR.NLM.   This NLM works with both the NetWare 3.11 server driver 
(SMART386.LAN); the NetWare 3.12/4.xx  server  driver  (MADGEODI.LAN), 
and the Client32 driver when in use as a server driver (CMDGODI.LAN).  

Use MMIRROR.NLM with:

SMART386.LAN version 5.xx or later
MADGEODI.LAN version 4.xx or later
CMDGODI.LAN  version 1.xx or later

Note:  This  release  (LSS  Release  5.0.0)  does  not   include   the 
SMART386.LAN driver.


3) Using MMIRROR.NLM
--------------------
A sample command line sequence is:

LOAD MADGEODI PORT=3000 NODE=400012131415 NAME=MADGE_DRVR [Options...]
LOAD MMIRROR BOARD=1 MIRRORPORT=4000 [Options...]
LOAD ROUTE BOARD=1
BIND IPX TO MADGE_DRVR NET=2

The .LAN driver needs to be loaded with a locally administered address 
(NODE=4xxxxxxxxxxx)  so  that  the  standby adapter can open using the 
same address.

4) Command-line parameters
--------------------------
The command-line parameters supported by MMIRROR.NLM are:

BOARD=x             (Always  specify  a board number). MMIRROR needs a 
                    board number.  If you do not specify  one  on  the 
                    command  line, you are prompted to choose one from 
                    a list of valid choices. (If  there  is  only  one 
                    valid  choice,  MMIRROR  assumes  that  choice  by 
                    default.)

MIRRORPORT=xxxx     (Always specify a MIRRORPORT address for  EISA  or 
                    AT  servers).  MMIRROR  needs a MIRRORPORT address 
                    (for an EISA or AT server).  If you do not specify 
                    a MIRRORPORT address on the command line, you  are 
                    prompted  to  choose  one  from  a  list  of valid 
                    choices.  If  there  is  only  one  valid  choice, 
                    MMIRROR assumes that choice by default.)  

MIRRORSLOT=xxxx     (Always    specify   a   MIRRORSLOT   number   for 
                    Micro-Channel servers.) MMIRROR needs a MIRRORSLOT 
                    number (for micro-channel servers). If you do  not 
                    specify  one on the command line, you are prompted 
                    to choose one from a list of valid  choices.   (If 
                    there  is  only  one valid choice, MMIRROR assumes 
                    that choice by default.)

BEACON=xx           Beacon is an optional parameter.  It specifies the 
                    number of seconds that the server driver stays  in 
                    beacon  mode before it attempts to mirror onto the 
                    standby adapter. Normally, ring beaconing does not 
                    cause the adapter  to  close.   If  you  use  this 
                    parameter,  set it to a value that is large enough 
                    to enable the ring to stop beaconing. For example, 
                    20 seconds.

                    Note that if  the ring  is  continually  beaconing 
                    and  the  standby adapter is connected to the same 
                    token-ring segment, it will fail to open. In  this 
                    case the two adapters will take it in turns to try 
                    to open until the ring stops beaconing.

LOBE=xx             Lobe  is  an  optional parameter. It specifies the 
                    number of seconds that the server driver allows  a 
                    signal  loss  condition  (caused  by  a  broken or 
                    detached lobe cable) to persist before it attempts 
                    to  start  the  standby  adapter.   

                    Normally  a  signal loss condition persists for 18 
                    seconds before the adapter closes and  the  mirror 
                    starts.   If you use LOBE, give it a value of less 
                    than 18.

SINGLE=xx           Single is an optional parameter.  It specifies the 
                    number  of seconds that the server driver allows a 
                    single station condition to exist before it  shuts 
                    the   primary   adapter  and  opens  the  mirrored 
                    ringnode.  This parameter enables  the  server  to 
                    recover from situations where the CAU has isolated 
                    the  primary  adapter.  Normally, the adapter will 
                    not close as a response to this condition, so  the 
                    mirror swap would not occur.

PIO                 Use this parameter if you wish to use a Smart 16/4 
                    AT or AT Plus Ringnode to mirror a Smart 16/4 EISA 
                    Ringnode in a server with more than  16  MegaBytes 
                    of  memory.   This  parameter  forces  the standby 
                    card, if called upon, to use  PIO  transfer  mode. 
                    (In  DMA  mode  it  would be unable to address the 
                    memory above 16 Megabytes.)

RESET               Only  use  this  parameter after a standby adapter 
                    has  been  successfully  linked  to  an  installed 
                    driver.   

                    RESET causes a mirror switch-over to occur.   Once 
                    you  have  corrected  the  fault  that  caused the 
                    primary Ringnode to fail, use the RESET  parameter 
                    to  switch  operation  back to the primary adapter 
                    and to put the standby adapter  back  on  standby. 
                    The  Board=x  parameter   is  required  with  this 
                    parameter. (If  there  is  only  one  valid  board 
                    choice, MMIRROR assumes that choice by default.)  



NOTE 1:
-------
You cannot unload  the  LAN  driver  until  after  you  have  unloaded 
MMIRROR.NLM. 


NOTE  2:
------- 
If you unload  MMIRROR.NLM  while  the  original  standby  adapter  is 
operating  as  the  current  primary  adapter,  the  standby adapter's 
interrupt channel is disabled.  (This does not apply to SMART386.LAN). 
To avoid this, first  reset  the  original  adapter  using  the  RESET 
parameter  (see  above).  If this is not possible, unload MMIRROR.NLM, 
then unload MADGEODI.LAN and re-load it onto the working adapter.

                     ***** End of MMIRROR.TXT *****